newbvetteguy

I've been lurking and I've read some of the really great FIRST builds on here for quite a while now and I'm getting to the end of the planning stage for my build; before I start spending a ton of money, I'd LOVE it if some of you could give my build a look over and make some recommendations.

Ken from FIRST is great, but it's really been pretty difficult to impossible to get any actual dyno results tied to real builds, flow #'s, or even cross sectional area #'s out of him. He is NOT a numbers guy although I know he's got plans to get much of his own equipment to start getting numbers now that he's recovering from a major building fire...

I've read BadSS's build thread probably 7 or 8 times now over the past 7 months. The same for 1979GTATransAM's. I also looked at the port / simple mini-siamese work that gbayfisher did, given that his 383 CI is much closer to my 350 CI build. Cuisinartvette has helped me out on numerous threads spread across half the internet, too -CF, SpeedTalk, and some great input here.

The weird thing is I'm taking a carburated Gen1 SBC and I want to put a FIRST-TPI-style intake on it to get hot and nasty torque.

Here's some details on my build to get started:

• 1979 Corvette L82 as the starting point (3,400 lbs)
• Profiler Heads (slightly modified casting from ATK Engines that has normal height exhaust ports) 195cc intake runner,
  Lift CFM Lift CFM
  0.200 144 0.200 107
  0.300 207 0.300 142
  0.400 250 0.400 172
  0.500 268 0.500 187
  0.600 270 0.600 196
  0.700 271 0.700 203
  0.800 273 0.800 207
• FIRST Intake that Ken's port matching to the heads' 1206 Felpro gasket; I'm thinking 1050 CFM throttle body
• Mike Jones fairly aggressive lobed hydraulic roller CAM; 110LSA, 107ICL, 227/232 @ 0.050"; valve lift with 1.5RR: 0.562"; IVO 6.5, IVC 40.5, EVO 49.0, EVC 3.0
• 10.2:1 static CR (0.015" felpro gasket); I believe 7.9 dynamic CR with the big cam recommended by Mr. Jones
• Flowtech coated long-tube headers 1 5/8" with 3" collector down to 2.5" true dual exhaust, no cats; high flow mufflers, 2.5" H pipe
• 355 rear gears
• Monster 4L60e transmission (rated to 450ft lbs / hp)
• 2300-2500 stall TC w high carbon content lockup clutch
• Holley EFI
• 7,000+ RPM capable short-travel Johnson/Scorpion lifters; dual hydraulic roller springs (I'll need to figure out pressures)

My questions are ultimately, whether the stock FIRST intake is going to become a significant airflow limitation for even my 350 and whether it will limit my HP on the top-end significantly or my RPM. I really want to shoot for peak HP @ 6,000 and my CAM is setup to do exactly that and continue without a huge drop off through 6,300 RPM.

-The MegaRam thread at the end brought into question really how much the stock base flows on the weak runners and I'm not clear on whether I should have the runners ported / extrude honed to support my 6,000 RPM peak in a 350 goals or not. --If so what inside diamter is ideal?

Should I do the "mini-siamese" that GbayFisher did to hit a 6,000 RPM peak on a 350 or does my 33 fewer cubic inches vs. his build effectively get me a few more RPM out of the FIRST than he got?



Thanks folks!
The insanely overly optimistic DesktopDyno spits out CRAZY numbers of 476 ft lbs (I've heard it's usually 5%-6% optimistic on torque #s) at 4500 and 469 HP @ 5500. But those numbers are nuts and it doesn't do any real simulation of the exhaust nor as far as I can tell any wave tuning-based estimates on intake runner length. I'd really love to hit 425HP fly wheel HP on this build.



Adam

no new tires

sub-

Orr89RocZ

iTrader: (20)

It should peak closer to mid 5000's and might hold to 6000 and start dropping off past 6250 imo

It will make good power tho

BadSS

Long story short --- What Orr said.

I don’t know if I’d agree that the flow numbers at the end of the thread brings in to question the flow capabilities of the FIRST, but it did confirm that 1 and 8 are the weakest ports. What I see is that when the FIRST is flowed by “sucking” like it does when the heads are flowed,, the FIRST base pulls around 300 cfm on the weaker port. That’s more than your heads flow. When the guy’s ported FIRST was flowed by “blow through” method, it registered 267cfm on average. When a single plane Super Victor was flowed in the same “blow through” way, it registered 271cfm. So I was actually relieved to know that a ported FIRST could hang with the Super Victor regarding flow capability.

I ran 12.5s in the heat with the FIRST on FAR less engine than you have. I shifted at 5800 into 2nd to keep from spinning the tires when shifting at 5600. Simulation estimated peak HP at 5400 rpm and I feel like that was pretty close. It also showed power didn’t really start to drop until around 6000 rpm and I also feel that was close as well. That’s because after my first test drive with the FIRST on the car, I thought the shift point was going to be around 6000. When I got to the track, I found 5800/5600 was the best shift points but when I shifted at 6000/6000 it ran the same times as 5800/5600 so I just shifted at the lowest RPM that didn’t effect ETs. When I shifted at 5600/5600 it would spin the slicks going into 2nd gear and ET would suffer about .07-seconds.

I’m talking about my old set up to say that when I run the EA simulation software on your combo, you should be making about 40 HP more than mine, peaking 440-ish around 5500 and shifting about 100 rpm higher (around 5900). You should also make about 50lb/ft more, peaking 485-ish around 4300 rpm with the STOCK FIRST. Anything you do porting-wise, either making the runners larger or notching them to reduce the effective runner length you will give up power in the 3800rpm range. For instance increasing the runner diameter from stock 1.75” to 1.85” should drop you around 10lb/ft from 3000 - 4200 and only give you about 7HP at a peak of 5600 – plus the power still drops off fast past the approximate 6000 rpm shift point. In this case you would be giving up more midrange power than that very narrow HP gain and near negligible peak rpm increase would give you. While peak power doesn’t really increase by notching the runners about an inch and keeping the stock 1.75 diameter on the runners,, it would be a better fit than enlarging the runner diameter as it loses very little TQ (less than 5lb/ft), but does make peak power at 5800 rpm and holds the power long enough you could probably shift in the 6200 rpm range.

All that said, I think the stock runner diameter fits your combination best and you would be more than just happy by doing some minor porting on number 1 and 8 on the base and bolting on the stock untouched runners. You can always take the runners off and notch them later if felt like you needed a little more upper rpm capability. I don’t think your quarter mile ETs would be much if any better, but the notch runner combo would pull fractionally better from a punch at highway speeds.

newbvetteguy

Thanks for the reply Orr89RocZ. I've appreciated your posts over here and on SpeedTalk, too.

I hope you don't mind me asking you to "show your work/ logic"; what makes you feel that it will peak closer to mid 5,000s just looking at the cam duration @ 50 compared to engine cubic inches, based upon your knowledge of previous FIRST builds, or are you using some sort of software? If software which one?


-I've been using the old-school Desktop Dyno from 2000 and it stated a peak of 5,500, too. I'm not sure whether it's the long runner intake wave tuning that's giving it this result (Desktop Dyno's intake info is REALLY simple and it doesn't let you enter runner length so I'm not sure how much trust to put in it) or the cam duration. I asked Mike Jones to select a CAM that hit a peak @ 6,000 RPM, which is part of why I'm asking the question.



Adam

newbvetteguy

There were some pretty abysmal results reported by that guy on the weak runners- far below the flow capability of my heads at the lift I'm looking at; that WOULD reduce the flow potential if his tests were accurate, which I understand is in question. The average data is good, but reducing the flow into two cylinders is still going to drop power.

I wasn't completely clear on whether your testing was with the runners attached to the base and whether your #'s were prior to basic cleanup and porting or if they were as the intake came from FIRST.


What do you mean by "with far less engine"? You didn't put a FIRST on a 305, did you? It was still a 350 with a FIRST intake on it, right? Are you just saying that your heads didn't have as good of flow #'s as the Profilers?


That is just incredible information that really gets me excited / optimistic! I can't believe a stranger I don't know personally through the internet would take so much time to put together such a well thought-out and labor-intense reply as this. Seriously appreciate it. This is the type of information I was DREAMING that someone would provide back, but I never expected I'd actually get.

What do you think of EA's accuracy / cost? (How much is it?) -I called about buying Desktop Dyno 5 yesterday, but honestly I think it's missing some features that should be included -it doesn't even calculate static or dynamic CR?? (You have to upgrade to the $100 version for that) You combine that with the fact that they have to MAIL you a CD (what year is it?!?!) and I was pretty turned off.

I did just buy PipeMax this morning (waiting on my code to get emailed) because I'm really finding the intake and exhaust wave tuning to be super interesting and this is probably going to be the first and last engine build I ever do so I want it to be done right.


What specific cleanup would you recommend to improve runners 1 and 8? I'm a total newb and haven't ever ported anything (although I might ask Ken to do it for me; lol!)...

Has anyone tried tuning the air /fuel ratio per cylinder on one of these first intakes before? Ken mentioned that the back cylinders are always going to get less air and run richer simply because of the back plenum wall being close to the runners for the cylinder's up front (because it has to make room for the distributor). -If someone did have detailed bolted-on stock airflow #'s could I do a simple calculation like "the 2 rear ports flow 10% less air, so if I trim the fuel to those cylinders by 10%, I should maintain a roughly equal AFR to those cylinders"? -There's no way I'm drilling holes in every header exhaust runners to get individual O2 bungs to fine-tune each cylinder's AFR, but my EFI does support different flow rates for each cylinder...


Oh yea, when should someone upgrade from the 750cfm throttle body(whatever the smaller CFM rated throttle body is) to the 1050 CFM throttle body? -A friend yesterday said that a 1050 CFM throttle body would just hurt throttle response and not provide any real benefits on a mild 350 like mine.



Adam

Adam

newbvetteguy

The average #'s are interesting and still useful, but the flow #'s in the weak runners that that guy saw were certainly below the flow #'s of my heads at even 0.050" lift, which WOULD reduce power, assuming his #'s were obtained accurately, which I understand is in question.


What do you mean by "far less engine" than I have? Was your FIRST build on a 305?!? or are you just saying that your heads don't have the flow #'s of the Profilers?

That's truly great information; more than I had even hoped someone might post. I can't believe that a random stranger on the internet would put in the amount of time that this reply must've taken; truly appreciate it!

Your #'s are really exciting me and are making it more likely that I'm going to pull the trigger and make my wallet way lighter; lol!

I won't bother porting, extrude honing, or mini siamesing it then and I'll just have Ken match it to a Felpro 1206 for me and maybe cleanup #1 and #8, if you can provide more details there. -I'm a complete newb and haven't ever ported anything so I could use the details, if you've got em.

I'm also curious if you've seen anyone measure the their air to fuel ratio in each cylinder with one of these intakes. Ken said that pretty much no matter what you do the 2 rear cylinders are going to run a bit richer than the other's because they're going to get less air because those runners are so close to the back of the plenum to make room for the distributor. There's no way I'm drilling 8 holes and installing 8 O2 sensors to measure the AFR in each cylinder, but if someone else has done this before I could roughly approximate the reduction in flow to those two cylinders, I could trim the fuel to those cylinders to end up with a more even AFR between cylinders...


Also a huge question I have: Do I really need/ would I see a benefit to going with the bigger 1050 CFM throttle body? My friend said that a mild 350 like mine won't benefit from the added airflow vs the stock 750CFM throttle body and it might make the throttle response more sluggish... -Any thoughts there?



Adam

newbvetteguy

What do you think about the EA simulation software? What's it cost?


I almost bought Desktop Dyno 5 yesterday, but I was kind of shocked at the features that are missing and that you can't actually download the software and have to wait for a CD to get mailed... (What year is it, again?)

The software doesn't even do static or dynamic compression ratio calculations until you get to the $99 version... wtf?!?

I did just buy a copy of Pipemax this morning (Waiting for my code via email to register it) as this will probably be the first and last engine build I do and I really want to do it right and I figured with the FIRST intake, I could probably use the software -plus it's a great opportunity to fine tune the exhaust scavenging and not leaving anything on the table to let those great heads breathe. The car's been in my family for almost 40 years and I want to give it a happy 40th birthday present! ;-)



Adam

newbvetteguy

UGGH! The forum keeps losing my posts; not sure if it's a forum problem or an Edge browser problem; switching to Chrome, let's see what happens.


How do you like the EA simulation software? What's the cost?
[Edit] Engine Analyzer: $109.99, Plus $199, Pro $499; Engine Analyzer's feature set looks pretty awesome!


I almost bought Desktop Dyno 5 yesterday but then I realize just how many features it was missing: no compression ratio calculations, no automatic rocker math adjustment, no pressure wave tuning -and then I found out that you can't even download the software after you buy it- you have to wait for them to ship a CD like it's still 1995... WTF?


I DID just buy PipeMax this morning, though as I figured it could come in handy with the FIRST intake and it's a good opportunity to really make sure the exhaust is dialed in. -This car as been in my family almost 40 years and this is probably going to be the only engine build that I ever do and I want the car to have a very happy 40th birthday. ;-)



Adam

newbvetteguy

BadSS, if you don't mind, I'd love if you could plug the same numbers as above in but with a cam ICL of 110...

Now that I got Pipemax working- it let me know that at that ICL that the cam was 3 degrees advanced (no, I didn't know that; still learning). When I set the ICL to 110, I saw no decrease in the Torque #'s at all but saw the max hp edge closer to 6,000 RPM and up by 9 HP. I'd be happy to take 9 free HP just for installing the cam straight up, but it seems too good to be true...


Adam

BadSS

I typically don't do anything this involved on the forums but I've got a bit of a soft spot for the FIRST intake. Plus, I actually miss doing this kind of thing. I used to do it all the time when I was working a lot on the side, but a new job and family health issues have all put stopped that.

The numbers he references are blow through numbers – they can accurately show improvements/gain when porting and can be compared against other intakes measured with the blow through method. However, you can’t compare blow through with pull through numbers. The FIRST, when flowed like your heads in the more commonly referenced pull through/vacuum method flowed 301 cfm on #1. So the weaker of the two ports does flow better than your heads. A Super Victor flows 335-345cfm when flowed in the pull through method – it only measures around 270cfm with the blow through method.

It was a 9.8:1 compression 355 with old TFS G1 heads flowing in the 240cfm range at cam lift of the 218/228-110 flat tappet hydraulic stick. I ran stamped steel rocker arms and the headers were crappy 1.625” shorties that came with the car. It only had a single 3” exhaust and one muffler and I was using the old runner gaskets that overlapped the base ports as well (the new FIRST gaskets don’t). You will ET considerably better than mid-12s with your combination.

That’s relatively common for a front mounted throttle body intake to have the back runners running a little rich. Unless you’re running a sequential fuel injection system where you can adjust the fuel for each cylinder, it kinda sorta is what it is. I adjust things so the leanest cylinder has enough fuel not to hurt anything and the rest are what they are. I can tell you there was not a lot of color difference on the plugs and I checked them often.

According to the simulation it is about 8 HP at peak with no benefit until 4500rpm. A larger T/B on fuel injection doesn’t have the same effect as too large a carb. If you get the tip in, fuel ratio, and timing right, you shouldn’t see much if any difference at part throttle. I think a lot of bad press comes from not making the proper adjustments for the increase in airflow or more accurately the reduced restriction.

I bought the standard EA back in 1992 and quit putting anything I built on the dyno. It basically mirrored every engine I had dynoed and all my friend’s engines had dynoed. I’ve updated the software over the years (they allow you to upgrade to a higher version of the software at a discount). While I have EA Pro, I don’t break it out until it’s one of my engines – I used to use it for customer’s builds, but it has been a while. I use EA Plus when I’m playing around on the internet since it doesn’t require near the inputs and time as the Pro version and it comes pretty darn close to the real results. However, I’m running a lot different cam in this 406 FIRST build than I typically use and did have it dynoed. EA Plus was 2HP off peak and 50rpm off peak. I won’t be dynoing anything else – lol.

EA Plus shows 7HP at peak and extends it about 50 rpm but it estimates a 10lb/ft drop around 3000. The up/down crossover point would be around 4200 with HP gradually increasing and TQ gradually dropping. With your stall speed, I’d do the 107IC, which as you said, is 3-degrees advanced. Any time you move the intake center up numerically (retarding) you’re going to trade a little lower rpm TQ for upper rpm HP and vise-versa. There are very few things you can do or buy that boosts low and high rpm power without hurting one or the other. Rocking the intake center up or down isn’t typically one of them.

newbvetteguy

Thanks, I saw that discussion but I didn't fully understand what was going on there or why the comparisons weren't valid; I think I finally get it.




That's great; I fear traction is really, REALLY going to be my problem. I like 17-18" wheels and I'm just not sure how wide a tire I'm going to be able to fit on the rear of the car. I KNOW 255s fit but that's not going to be close to enough for this kind of torque; I'd love to fit 285s but I need to do some more research there.



That's some pretty high praise and great results. I just wish it was about $50 cheaper and I might be able to justify it. As I'm only doing one engine build ever (*knock on wood*), it's hard to justify $110 for engine sim software even though I really enjoy playing with it and learning the impact of changes.




In general going in, I'd happily take 10ft lbs vs. 7 hp; but with the numbers EA is spitting out, I'm afraid I'm going to have far more torque than I can use especially with the 3.06:1 4L60e's first gear and my 355 rears...

Probably should've just bought the 2.84:1 new 1st gear for the transmission when I ordered it, but there was no way I could justify $500 for a 1st gear change..

Part of me feels like I have way more torque than I can use and trading for some higher end HP might be better, but then again, I have such a low cruise RPM with the 0.70 OD gear that I'll want some of that torque down low to help with cruise torque / MPG so I'll probably leave things as is.


Adam

newbvetteguy

Also, I'd happily take any advice anyone can give regarding using Pipemax.

When I input all the information regarding my engine (except for valve stem diameter which I don't really know; I put in .3438, which seems reasonable); in order to get up to an average of 440 HP I had to set the Volumetric Efficiency % at 120% which seems laughably high. -I put peak HP RPM in at 5,500 RPM as that's what both EA and desktop dyno were reporting.


Getting things to 440hp average yeilded 465 ft lbs. HP per CID avg was 1.258 and ft lbs of torque per CI was 1.332 --those numbers are very much in alignment with what I was expecting. It's just a VE% of 120 for a naturally aspirated setup that seems kinda crazy but I guess with decent exhaust tuning and intake tuning focused on torque, I guess it could be possible...


Adam

BadSS

I had to put a lot of heat in the 26x10.5 slicks at the track with my 355FIRST to get it to hook with the 2.52 first gear and 3.23s. However, my stall would flash to around 3200rpm with the FIRST - only around 3000 with the HSR. With your lower speed stall converter you should be OK - assuming a sticky tire. It was a little tricky to launch on the street with 245/45/17 555 Nittos but was manageable. Hopefully you'll stuff as large a tire on it as possible and you should be OK. It should be a blast to drive regardless.

Don't know much about PipeMax but EA is showing 110.5% at peak torque. Don't know if this is helpful or not, but I've found that with EA you get much closer to the actual dyno data when you enter the straight line or most direct/shortest measurement for the intake manifold. On the FIRST that measures 14.25". Adding the SBC head port length of 5" yields a total intake tract length of 19.25".

newbvetteguy

Well, at least I've got my lower stall TC working in my favor.

You had an effective 1st gear torque multiplication ratio of 8.2:1 with your 2.52 1st gear and 3.23 rear gears; I've got 3.06 1st gear x 3.55 rear gears == 10.9:1 effective 1st gear torque multiplier...

I'm going to need some huge, fat rear tires... I'm probably going to annihilate my differential, huh?

Might wish I had just bought the 2.68 1st gear, but that would still be 9.1:1... (Maybe I should just leave in 2nd with an effective ratio of 5.75:1 -Lol! How awesome would it be if I could do a burnout leaving form a stop in 2nd gear?!? -Crazy FIRST intake making this possible...)


110.5 VE at peak torque is good information; appreciate that, I'll feed that to PipeMax and then get on the PipeMax forums and figure out what went wrong with the estimates.

Great to finally get some good information on runner length with these FIRST intakes; I thought they were 22" --that was one of the things that was making me think that notching the runners was a good idea. (I couldn't comprehend why anyone would go with a runner much over 19" in length.)


Adam

newbvetteguy

I just found out the max rear tire width my 79 Vette will support is 275/40-18s with the 18" wheels (9.5" width w 5" backspacing) that I like. I can at least go with some sticky compound summer tires to get as much traction as possible but I realize I'm still going to be traction limited.


I was starting to get depressed at just how traction limited this setup could be when I remembered that I can just buy an aftermarket traction control computer and a drive shaft sensor (Davis technologies) that works with my Holley EFI. Not cheap, but high tech and rather simple, so the solution is to my liking.


Adam

BadSS

I've done a lot of research on tires and suggest you do your own, but check out the reviews on the forums for the Toyo R888s. They make a 275/40-18 and I'm considering that tire myself.

I don't know anything about the Davis traction control, but I've just pulled timing out of the WOT timing column for traction limited vehicles. It's a little time consuming to get it right but it should work really well for you considering your stall speed. Just take timing out between your stall speed and the lowest shift recovery RPM (should be from 1st to second). That has worked well for me.

TORN

iTrader: (17)

[QUOTE]Also a huge question I have: Do I really need/ would I see a benefit to going with the bigger 1050 CFM throttle body? My friend said that a mild 350 like mine won't benefit from the added airflow vs the stock 750CFM throttle body and it might make the throttle response more sluggish... -Any thoughts there?
/QUOTE]

On a 350 no way, I just removed the 1050 CFM throttle body off my 421 cause I couldn't stop a tip in bog. I will report back if the smaller (stock) TB fixed or changes anything else.

newbvetteguy

A 421CI FIRST build?!?! Do you have a build page here or anywhere else on the internets?

This I must see!


Adam

TORN

iTrader: (17)

Yea I posted a build here. I can post a link if you can't find it.

newbvetteguy

I found it. https://www.thirdgen.org/forums/engi...ion-421-a.html


Did you ever get the beast on a dyno?


Adam

TORN

iTrader: (17)

Nope, still tuning. I am slow. LoL

newbvetteguy

Quick update:

• I picked up a set of Jegs-branded Profiler 195cc heads on a crazy Christmas deal with dual 1.440" hydraulic roller springs (.600" max lift), bought some 7/16" rocker studs to swap out for the 3/8" that they come with.
• Ordered my Mike Jones hydraulic roller cam
• Got my EFI fuel system figured out- order coming tomorrow
• ALMOST ordered my FIRST fuel injection intake

Now I'm running into a conundrum I'd like some feedback on:

I've been looking at Precision Race Engine's crate motors that come with FIRST Intakes and I've been talking to Adam @ Precision. The bottom line is that the out-of-box FIRST intake hits it's airflow limitation @ 425 HP with a 4.000-4.060" bore; it doesn't matter if you have a 350 or a 383 or a 396; at 425 HP you're all done.

-This is honestly not a bad trade off for my 350, IMO, getting 30-40 extra ft lbs in exchange for 15 hp. (With a good dual plane intake my heads, RRs, and cam could hit 440HP.)


BUT- my bottom end is still from 1979 and I'm going to have to refresh it; I plan to go to a 383 stroker and I'd like to see the HP much closer to 500hp than 400 HP then. The Precision 383 with Brodik 200cc heads hits 500 ft lbs with a stock FIRST; the CSA on my Profilers is a bit smaller and I think I'd hit slightly more than that which would be problematic given that my 79 Vette can fit a max width tire of 285s without flared fenders and I've got a 355 rear and a stupid torquey 3.06 4l60e 1st gear. --The point of all this is that I'm probably going to have way more torque than I can put to the ground and I'd probably be better off exchanging some torque for HP.


I could send the intake off to get extrude honed when I want to go with a 383, but how much can you safely open it all up? (From 1.75" ID to 1.85"?) If so, what would that do for me? -Extrude Honing costs $800 for something like this -that's almost the price of a whole new intake...

I could buy an AFR Titan dual plane and have someone put EFI bungs in it and still have money in my pocket and 15 HP more now and like 75 hp more on a 383 build with a bigger cam...



Maybe I'm just getting gun shy, but I really want to think this through.


Adam

TORN

iTrader: (17)

I am not buying that the First intake is ALL done at 425 Hp. Heck guys are making 425 on the stock TPI setup. I am not sure why he's feeding you this info its is dead wrong.

newbvetteguy

No one's making 425hp on the "stock" TPI setup; that's a very misleading statement. The insane lengths people have had to go to to get 425hp out of a stock TPI isn't anything remotely resembling "stock". (I know what you're saying that although they've hugely modified the plenum and entrance to the runners, and added bigger runners, and welded more metal to the bottom of the intake to accommodate larger head intake ports, and dramatically ported the base that the hunk of metal was originally a stock TPI intake, but "stock" isn't a fair word to use after you've done all that.)


Here's a real 383 crate engine with a FIRST intake, Brodik IK 200cc heads, and a 224@ 0.050" cam (although a Comp XFI series--EW!); 425 HP, 500 ft lbs torque; it's using the newest gen FAST EFI so this isn't an EFI limitation holding it back, either:
http://precisionraceengines.com/crat...-engine-425-hp


Dyno doesn't lie.


How much air do you think can be pushed around a curve through a 1.7" runner/ CSA?

If you look at a modern high-velocity head like the AFR Street 180 or 195 heads or the Profiler 185 or 195cc heads you will see the airflow quickly drops off at a certain RPM (let's say 6,200 on a 383 as an example) -you'll see the CFM increases quickly drop off above 0.600" lift. These are what Darin Morgan calls "velocity-limited" head designs. To get such great torque out of them the CSA at the pinch point is kept small ish for the CFM airflow and trying to pull more air through the pinch port causes the port to go turbulent; the 210 cc version of these same heads has a large CSA but the rest of the port is mostly the same and the airflow numbers go up another 30 CFM because the flow doesn't go turbulent as the CSA is wider.

The Profiler heads have a 2.15" CSA for the 185cc version and 2.19" for the 195cc version. The FIRST intake, although it has a MUCH larger inside diameter than a stock GM TPI intake, is still only 1.7" ID. That's SIGNIFICANTLY smaller than the head's choke point / CSA of 2.15/ 2.19. It's going to choke sooner and not be able to flow air sooner.

The dyno results from Precision Race Engines seems to indicate that the party stops at however many CFM it takes for those Brodik IK 200s to hit 425 HP.


I'm not a PipeMax wizard like a few people on here but I have to think if you open up the FIRST intake (or cast it) such that the minCSA / end-to-end ID of the FIRST intake is 1.85" instead of 1.75" you'll get more airflow at actual engine operating velocities and the HP limitation would move up.

If Extrude Honing wasn't the greatest rip-off in the world, I'd happily use mine as an experiment, but extrude honing prices are absolutely bonkers for just pushing some silly putty mixed with sandblasting media through my intake.


Adam

newbvetteguy

Ken needs to man up and just pay a reputable engine builder to put a FIRST intake on an appropriately matched 350, 383 and 400 and just get the dang dyno sheets.


All these questions continue to come up again and again and again because of a lack of objective, verifiable data from a reputable source. He's trying to say that long-runner intakes don't automatically / inherently HAVE TO limit power and that they can have HUGE torque AND great power if you just get a bigger straw. And of course many people here on Third Gen have gone to great lengths to show us that that IS true, but the # of dynos are so small and they're all wheeled dynos and most of them are modified intakes; the data on what an out-of-box FIRST can do is hugely lacking despite the thing being for sale for DECADES. The only way the long runner myth gets busted is by paying for the engine dyno sheets.

It's been a couple of decades now; it's so far over due it's pretty ridiculous.

People's assumptions about TPI intakes should be REFUTED because of the FIRST intake but the lack of engine dyno results PROOVING it, does just the opposite. -Scan the FIRST intake posts in this particular forum, people chime in with things like "FIRST intakes are a scam for people who don't know much; just buy a holley stealth ram"; all this can be solved by a very simple and not that expensive engine dyno sheet -unless the detractors are right and FIRST / Ken have more to gain by NOT posting a dyno sheet because the thing and it's 1.7" ID runners choke the engine and kill HP just like the OEM TPI intakes (and just like a 1.7" CSA at a head's choke point would do), although at a higher HP (425HP according to the only engine dyno result we have).

Only the dyno can pave the way towards making it better, too.
Right now the only engine dyno results we have say the FIRST and it's 1.7" ID chokes HP @ 425 HP on a 4.000"-4.030" bore. Until someone can provide engine dyno results that say differently, I think the existing dyno sheet is the most authoritative source of objective data on an out-of-box F.I.R.S.T. we have available.

Ken invested in a booth at SEMA before investing in getting dyno sheets; it's not like he's not willing to invest in the product to drive sales.

Would anyone contribute to a GoFundMe page to get this stupid thing dynoed by a reputable engine builder? (only half joking right now)
I'm going to ask Santa for an engine dyno test result for Ken.


FFS -Putting this here to help the Search Engine
First Fuel Injection
firstfuelinjection.com

Adam


Yes, I'm frustrated; I want to buy this thing and I want it's purported benefits, but before I spend my hard-earned money, I want some basic assurance from an objective verified 3rd party that it does what it says it does. I want objective, quantifiable information; it's honestly not asking much. It's a reasonable ask. The lack of a dyno result brings into question whether it does what it says it does and "how much" it does what it says it does. I'm trying to make a value decision to determine what I get for how much I spend. Without NUMBERS from an engine dyno, I don't know what I'm getting other than "more torque". There's a supposed money back guarantee, but what a pain it would be to select a CAM and build my whole engine around this thing and buy fuel injectors only to find out that it chokes my engine by 75hp and I want my money back to go with a dual plane intake and TBI EFI, instead. -A money back guarantee is not a replacement for just telling me what I am getting for my money in the first place.

BadSS

Cross sectional AREA is not the same as diameter. The CSA for a 1.7” inside diameter runner is 2.26”. The inlet diameter of the FIRST base is approximately 1.85” or 2.68” CSA. There’s not a pinch-point issue on most off the shelf heads.

The following link shows a Big Mouth TPI intake making 450HP on a 383 and there is NO doubt in anyone’s mind that has ever seen a FIRST in person that it is a bigger and better designed intake system. Flow comparisons from the CA folks show a stock type TPI base like the BigMouth ported (not welded) is around 265cfm and the box stock FIRST on the same bench flowed 300cfm.
http://www.corvetteitalia.it/public/...2201093121.pdf

So, I don’t know what Precision is “seeing” or why they’re talking about a 4.06” bore limiting the intake power. The intake is bolted to the heads and bore diameter has NO direct correlation with an intake manifold flow. Now,,, most all SBC heads will flow more on a larger bore and subsequently so will the head/intake combo, but saying the FIRST is limited to 425HP on a 4.06” bore is ridiculous. Obviously it is on their dyno with those heads and the cam they’re running though.

So, here’s their 425HP @5800 / 440lb/ft @3500, 10.5:1 compression 383 using the IK200 heads, Brodix HP1 Dual Plane Intake, and a 230/236 cam
http://precisionraceengines.com/crat...-ez-efi-425-hp

Here’s their 10.5:1 compression 383 FIRST combo with the IK200 heads making 425HP @5500 and 500lb/ft @undisclosed RPM with an undisclosed cam. I would assume the cam to be the same or smaller than the one above.
http://precisionraceengines.com/crat...-engine-425-hp

So, it looks like their dyno and the heads they’re using, not the intake is the limiting factor with their engines.

newbvetteguy

Thanks for setting me straight; I need it.

Newb mistake on the diameter vs. CSA for sure.


I'm trying to give Ken my money; hopefully he'll take it.
In the meantime I've got plenty to do to get ready for it, I guess.


Adam

newbvetteguy

Update: I got distracted by totally replacing all my fuel lines and doing the EFI fuel system conversion and rust remediation on my car. Now I've started pulling parts off of the top of my engine and can finally start putting more attention on the engine, where it belongs.


BadSS, If you're still lurking and still have time to play with EA/ EA Pro, I'm really curious if EA can model different valve seat profiles.

I started a thread on 50 degree valve seat angles on SpeedTalk that really exploded and took on a life of it's own and I'm now convinced that 50 degree seats on a combo like mine and particularly on many high-end long-runner SBCs could really be pretty magical on these motors.

The 50 degree seats increase the average speed through the intake track, increase high lift flow, help prevent reversion AND help make wave tuning effects stronger.


I'd be super curious to see what EA / EA Pro says would happen to a good long-runner SBC with slightly too big of intake port heads with 50 degree seats (and supporting top and bottom angles). The Profiler 195cc have a slightly too big min CSA for a 383 @ 6,000 RPM (2.15", which is roughly where the AFR 195cc RACE heads are; the 2.19" min CSA of the 210cc Profilers would DEFINITELY be good candidates for 50 degree seats, IMHO.)


My same cam on a 107 or 108 LSA I think would show even better results as we know that the Torque / HP Peak will be better on a 383 than with a 110 LSA but the overlap gets pretty serious there and reversion would be more of a problem, but the 50 degree seats should help with the reversion and taming of the idle (not sure about vacuum...).



Adam

Orr89RocZ

iTrader: (20)

Are they using box stock ik200’s?

I believe a faster port afr 195 would make more power or a well done chamber profiler 195. Those are hreat castings as long as they are done by someone with skill. But out the box they are pretty good too

BadSS

For 6000 rpm on a 383 you’re looking at a target of 2.10” MCSA, a 2.15” MCSA yields 6150 rpm. There would be a near negligible difference assuming equal or near equal flow numbers – definitely not something to worry about. The volume of the port in and by itself mean little to nothing. In fact when porting a head, I consider it a byproduct of the combination of the desired MCSA and flow needed to meet the power objective. Don’t get me wrong, you don’t want any more volume than it takes to get those numbers but the drivability and power under the curve has more to do with the flow per cc (efficiency of the port) than the volume of the port in and by itself. When you’re buying an off the shelf set of heads and not doing custom porting, considering how hard it is to get numbers for the MCSA of some heads, comparing the flow per cc is about the only way to help determine which should be the most efficient and consequentially the more responsive head.

The heads I’m running on the 406 FIRST build was ported in 1992 with a 2.42” MCSA to peak at 6500rpm while flowing 325cfm at .650 lift – volume is at 242cc. While there are a few off the shelf heads available now that would be better suited for my 406 FIRST build, I have no concerns at all using the old heads on a combo that I believe will generate a 5800rpm peak and around a 6200rpm shift point. In fact, I believe that the larger than “optimal” MCSA and volume may actually be beneficial to the increased filling effect considering the power I expect to make. I know that’s a lot different than the typical high-velocity thinking associated with a stock-ish TPI combo, but a max ported FIRST and this combo is far from the norm.

Anyway, if I were you and if your heads already have a valve job and is ready to run, I sure wouldn’t spend the money on another valve job or even go with another cam. While I understand you wanting to do something one time, it took me a LONG time and building a number of engines before I got to that point - part of that is knowing what to worry about or not. One can overthink the snot out of anything – sometimes you just have to go with it. I doubt very seriously you’ll kick yourself for not doing the 50-degree valve job or changing cams once you get the thing running – it’s going to be a fricken blast as is.

newbvetteguy

I came up with the same #'s and have switched to evaluating heads based upon the MCSA, too so it's nice to have confirmation from someone who's been doing this for a while.

I know a 210cc head on this combo would be a WAY better candidate for a 50 degree seat. My thinking was that my Stan's Tri-Ys on a 383 are going to start on limiting power from 5,500 RPM on up so the intake tract's extra ability to generate power higher might be wasted and maybe the 50 degree seat would gain more power in the mid RPM range.

The novelty of the 50 degree seat and the fact that there's so little side-by-side data and that in theory it could really help with the goals of a high-end long-runner intake was just really appealing. I'll probably abandon the pursuit of the 50 degree seats as the one chance I had for free labor that would make this irresistible to me just won't work on my timeline. This car is sitting in my garage in the way of my electric home brewery and I just had to push it out of the way to brew yesterday so it's getting me more motivated to just get it running as soon as possible.



Adam

no new tires

Stick to the plan, don't run out on it.

newbvetteguy

Thanks. I need the reminder.


Just blended the throats on head #1 yesterday.

Won't be able to get to the 2nd head for another 2 weekends--- UGH!
I screwed up one valve stem seal, so I'll need to order another one of those.

-I actually HATE how much the super thick valve stem boss sticks into the exhaust ports but I don't want to shorten this because it's a street motor and now that I've decided to stick with the 45 degree seats, I want EVERYTHING to last. -Anyone know of a tool that I can use to THIN the part of the guide boss that sticks into the exhaust ports? (I could do it with my dremel's carbide burr or 80 grit flapper rolls (I've got LOADS of them), but there's no way I'm going to be able to make it all even and pretty- I just dont' have that skill yet.


I've got standard 11/32" diameter valve stems and I'm assuming 0.530 valve stem guide bosses (that's the OD of my valve stem seals and they perfectly match the diameter of the guides) -will THIS tool thin the outside diamter of the guide bosses? https://www.summitracing.com/parts/p...45?seid=srese1

Yea, I know I'm probably chasing like 1 CFM, but I don't care, I've polished the exhaust ports, cleaned up the chambers, chased the spark plug threads, measured spring heights, replaced seats, shims, springs, retainers & keepers, and blended the throats, so I might as well thin the stupid guide bosses and just sleep well knowing I did everything I can reasonably do as a hobbyist at home.


Adam

charlie6178

iTrader: (2)

BadSS

The last set of Profilers I had my hands on just had the "naked" guide sticking out in the port without any surrounding material that you see "shaped" on most other heads. If they're still "naked" I wouldn't take any material from the guide at all - what ever small increase in flow wouldn't justify what you would lose in strength and reliability. Pretty sure Speier Racing doesn't shape the naked guides on their biggest and baddest set of ported Profilers.

newbvetteguy

I stopped getting email notifications from ThirdGen threads for some reason. -I got a guide cutter and shortened the amount of guide sticking out and shaped it into a bullet-nosed shape with a rough carbide. I polished the exhaust ports, too. I've got only a 2 degree @ 0.050" and a 4 degree advertised duration split from intake to exhaust so I think these heads could use a little bit of help on the exhaust side, anyway.


Adam

my hemi

I know this thread is older I'm building a 383 stroker,lpe219 cam,a 1st performance intake, with a set of 113 heads ported and polished by tpis they flow 250 cfm at .500 lift I'm using 1.6 rockers and tuning is being done by a holley hp efi system.. 1 im.hoping this makes decent power being reading alot of threads seems maybe the 1st intake will be the limiting factor? Any help will be great

newbvetteguy

Heads are your limit right now, then cam.

my hemi

Cam is what lingenfelter used..and heads are close to what they used this is kinda a old school build with newer tuning capabilities I'm wondering if it will perform well..I'm looking for mid 12s out of it..3450 lb car.. gm 9 bolt 3.27s worked 700r4 2600 stall convertor.

Chad Speier

iTrader: (1)

If anyone wants to know how accurate PipeMax and Controlled Induction is, here is my testimonial.

PipeMax is all I use to size cylinder heads.

http://speierracingheads.com/software-testimional.html

Troy Michaud

I thought I replied to this yesterday... but can't find the post. Anyway - based on content here, this might be a great place for these questions. I am curious about Cam choice, and if I need to port the FFI intake (First fuel) This is a build that has been stalled for years... looking to get moving again in the spring. Engine is going into my 1986 'vette auto.

What I have
406ci, stock crank, new 5.7 rods, flattop pistons (compression likely will be between 10.5 / 11 with thick gasket)
1.6 roller rockers
First Fuel intake (for Vette - they machine the top of throttle body for the C4 vettes fitment)
Profiler 210 heads, 1.055 intake 1.6 exhaust, ported - bowl blend, valve job, intake 1206 match.
PBM /Erkson 1.46HD springs (good for .650 lift I believe)

I need a camshaft (looking roller)

What do you guys think in terms of camshaft selection, given an auto, with a target range of peak power 5500-5800? Do you think I need to port the runners / notch the runners to get there?
Thoughts on overall power?

my hemi

Look at the lpe219 cam by lingenfelter that's what were using in our 383 build with a 1st performance intake.

Orr89RocZ

iTrader: (20)

For a 406 and that compression i would go bigger than the lpe. More like a 288hr comp or equivalent. Maybe an xfi based custom, the 280 xfi on a tighter lsa to bleed some comp off. Maybe closer to a 230/242 exhaust lobe to keep evo earlier to help.

Troy Michaud

Interesting... I was wondering about a cam to bleed off some compression. Would it need to be custom? which company should I talk with?

Thoughts on power level with this build? Would I need to do any porting of the FIRST aside form the intake port matching for my goals?

Troy Michaud

I had been looking at that one.. seem a REALLY good choice on a 383. Just worried it might be a bit small on to 406.

my hemi

lingenfelter says it's good for 383 to 400 cu in..might be a little small but heard great things about it that's why I bought it for our build with the first performance intake i also had Ken port my TB to 76mm vs the stock 71 mm TB

Orr89RocZ

iTrader: (20)

yeah most shelf grinds are 110 and wider lsa. You can do pretty good with xtreme energy grinds on 110 lsa. The 288hr hyd roller 236/242 would not be terrible for something like this. A good strong combination with a good head. I can see it approaching 400 whp and alot of torque but it will likely be done by 5500 rpm. The first base is suppose to flow close to if not around 300 cfm, which matches the head well. A 236 deg lobe imo matches mid high 5000’s rpm peaks. I think it be a good match with 1.6 rockers.

a custom lobe can get you into more aggressiveness and more lift which a 406 may like. At the expense of spring life and valvetrain noise to some extent. All depends what you use

BadSS

The base has an approximate runner opening of 1.85" while the runners themselves are "only" 1.75". I'd recommend opening the top of the runners and the plenum to about 1.9" and open the bottom up to 1.85" to match the base. It's not that hard to do but takes a good bit of time even with an air grinder.

You will need at least a good 6" shank 1/2" oval burr to be able to get to the entire length of the outside curve of the runner (buying a larger one in addition to will take you less time - well worth it IMHO) You won't be able to get to about 1.5" of the inside curve of the runner and even then the runner ends will need to be fully ported to do that. However, you can open the runner up a little more on the outside curve to compensate. I hope you can do the porting yourself as it will be quite expensive to pay someone to do it (time-wise).

newbvetteguy

If you’ve got the spring that can deal with it, you got the cubes and minimal rpm goals so go with a modern high intensity lobe.

I agree with Orr89Rocz on the XFI lobe and tighter LSA. Look at the QXI lobes if you want to see the crazy extreme aggressive hyd roller grinds but you’d probably still need new springs.

You could always fill out the MikeJones form and see what he’d recommend.

On the LSA, I don’t know what a flashed third gen ecu can deal with in terms of overlap; that would be my concern unless you were going with an aftermarket EFI solution.

If you’re considering a custom cam, you should look into the benefits of a firing order swap as I think the benefits with a TPI style intake are more significant than most. I know Mike Jones is only $50 extra for a firing order swap SBC cam... I wish I would’ve looked into it before I ordered mine.

Adam