So, some of you may already know my plight . I have a 355 with an Edlebrock TPI set up – aluminum Edlebrock heads, baseplate, runners and 58mm TB – along with a Crower roller cam (213/221 @.050 and .503/.525 gross lift). With the small combustion chamber on the Edlebrock heads, my compression ratio is about 10.8:1. I hadn't ported the Runners to the Plenum so I was probably having some restriction problems there. SO, at the rear wheels, I made 343 lb/ft of torque at 3500, but my peak hp was only 243 at 4000 rpm.

SO, I decided to take my shop’s (and some of your) advice and replace my barely used Edlebrock heads with a pair of AFRs; exchange the barely used Edlebrock runners with a set from Arizona Speed & Marine; and change out my cam for something a bit more aggressive (maybe 222/234 @.050).

NOW, however, the shop wants me to get rid of the TPI altogether and buy a miniram set up from TPIS – I spoke with the TPIS guy and frankly, he sounded like a used car salesmen; needless to say, I didn't trust him very much, particularly since the guys at AZ Speed and Street & Performance both said that the TPI was a better set up when coupled with good heads and a good cam. However, my shop thinks TPIS is the best thing since sliced bread and wants me to get all my parts from it.

SOOOO, here are my question:

SHOULD I KEEP THE TPI SET UP THAT I DESCRIBED ABOVE (AZ Speed runners ported to plenum, Edlebrock baseplate, and ported 58mm TB) TO GO WITH THE HOTTER CAM AND THE AFR HEADS OR SHOULD I GET A TPIS MINIRAM (which'll cost an *** load of money before it's all over), INSTEAD???

I mean, will the miniram really demonstrate a significant difference in power OR will it be virtually the same as the TPI????

I've also looked into the stealth ram and that'll just be exchanging one headache for another - I heard it won't fit under the hood properly and I'll definitely won’t be able to use my strut tower brace with it - so I'd end up spend whatever money I saved on a new hood.

ALSO, it's important to note that I DON'T PLAN ON TRACKING THIS CAR - not at the drag strip anyway; I just want to drive it around town, but be somewhere in the 400+ hp power range at the rear wheels if possible.

WHAT DO YOU GUYS THINK?????

 

Personally.. i think the mini ram is extreamly over prices. I was lookin at it and the stealth ram... well for the price the stealth ram won! Deff go with some good heads... and as far as the cam dont forget to match your torque convertor to your power band!!!

I know ya didnt list the stealth ram as an option but it really should be

 

I actually looked at the stealth ram - but I heard that it won't fit right and then I'll have to buy a new hood and that's a whole other big headache....plus my strut tower brace will also have to go....so frustrating.

As far as the tranny - I have a stick so I don't have to worry about the torque converter.

 

well i have a 3" cowl on mine.. so i dunno about clearens problems..... as far as the t-5 tranny... hope ya got some spare ones laying around ur gonna need them

 

I'm going to re-build it and beaf it up - it's a "world class" model so it should hold up fine - although with the centerforce clutch, it may not...we'll have to see once i get the damn thing running.

 

Think you will find the HSR is worth the effort

Completely different characteristics if intake matched to correct cam
See Hp /Torque graphs here
http://www.compcams.com/Community/Ar...?ID=1737510521

 

Some ppl never have a problem with them others have no luck at all...it all depends on your driving style... i was lookin into changine over to a T-5 because i havent been able to keep a 700r4 in it....but from what i've been told by ppl... once you break the 300hp mark...your on borrowed time

 

I converted mine to a t-5 and it was AN ABSOLUTE NIGHTMARE!!! It's not as easy as you'd think.

 

yeah i decided to baby a stock 700r4 till i can find a t56... so im on the hunt..

 

This is a great article - I was directed to it by the owner of Speed & Performance since they actually participated in it. The problem is that the engine they used was a 383 which needs a lot more air than a 355. But yeah, I think this article shows that the TPI isn't too far behind the HSR or the miniram if paired with a good cam and heads.

 

I have ran with both combos ( TPI & HSR...not at the same time... lol; but, I have NO personal experience with the MiniRam). The difference between the "max effort" TPI and the HSR is top end rev-ability and upper RPM horsepower. The TPI set-up will deliver abit more low-end and mid-range torque, but will drop off horesepower in the upper RPM's. The HSR and MiniRam will pull harder up top, but sacrifice some low end and mid range. I liked mellowing out some of the over-powering low-end torque my TPI set-up had. Now, some of the really max-effort TPI set-ups (like Dyno Don, 1989GTA TransAm, Kevin91Z) have been able to extend the upper R's more (see the thread 'Quest for a better flowing TPI') than I was able to with TPI. My runners were only siamesed about 2" in. I see you live in Los Angeles; neither the MiniRam nor the HSR are "smog legal." That may or may not be of concern to you.....

In conclusion to this long-winded ramble, let me see if I can attach graphs of my dyno runs, one with TPI, one with HSR.....looks like I can't. So, see thread 'dyno day 02/16/08' and thread 'stock block 350 lays down 387 / 376 rwhp' for the results I achieved with TPI and HSR, respectively. The only difference from the TPI dyno run was: 1) the intake; 2) a mildly modded air-lid; and 3) a Magnaflow muffler instead of a Flowmaster muffler.

Myself, I really like the performance with the HSR (-BO91).

 

Rambling??? That was VERY helpful; THANK YOU!

Did you have problems fitting the HSR under your hood? I just don't feel like getting the HSR to save $700 only to spend $800 to get a new hood, etc.

At the end, this "project" needs to make some sort of financial sense. I bought the car for $4000 when I was 17 and in recent years, I've spent over $10,000 just on the engine! The only reason I'm not cutting my losses is because I've gone past the point of no return. Most of the costs are associated with all the re-dos that I've had to go through. If there only was a decent performance shop out in LA that knew what to do with these cars, I wouldn't be in the mess that I'm in now. The place it's at now is a viper performance shop where I get my viper worked on so I figured they could do it - WRONG! They call me and tell me how they're learning new things everyday - AT MY EXPENSE! SUCH A NIGHTMARE! Thanks for your help though. I'm going to check out those threads you suggested now.

 

For a fun street car, I would just keep the LTR set-up that you already have. You have two beasts in your stable, so why not keep the RS a 700R4/TPI cobmo for fun grocery-getting? I have a worked Z06 for when I want to drive fast, so plan on keeping my L98 street fun/friendly as a nice-day daily-driver.

 

In my opinion, if you're going to go with AFR's and a new cam, I'd ditch the TPI setup. You should get a nice flowing intake to go along with those nice flowing heads.

I had a bolt on L98 with a stock stall and 2.77 gears. Last summer I installed a HSR intake, AFR 195's, and a comp cam. I also drove it all last summer with the stock stall and 2.77's, and there was still plenty of torque. Enough to still roast the tires. Needless to say, if you match your stall and gearing to your new setup, I would not worry about lack of torque with another intake. Having my car pull to 6000 rpms is also a really nice feeling compared to the TPI that choked out up top.

The HSR fits under my hood, but barely. You can see slight marks in the hood insulation where it hit when the engine torques. But nothing crazy. I'd go with a HSR if I were you. Just my opinion though.

 

You're right - it's just that I've spent SO MUCH money on this thing, I want to make sure that I get the most out of it - and I'm getting so many different tid bits of advice from everyone I can't decide - IT'S DRIVING ME CRAZY!! But I'm definately leaning towards keeping the TPI set up like you said and just being done with it - plus, I thought the best thing to do is to get the car to make power in the band that it's driven in - I don't see myself driving it at 6000 RPM much. By the way, it's a T-5 now - I got rid of the 700r4 when I was in college after I blew it 4 times and the warranty had run out - that was a total nighmare too which took a few years off the end of my life.

 

SEE WHAT I MEAN?? He's right too! I CAN'T DECIDE!!! I FEEL LIKE A WOMAN!

 

Well, not to make your decision any harder But if you're going to put in AFR's, and a nice size cam. You are not going to get the most out of it keeping a TPI setup. But if this is just going to be fun cruiser that's not going to get raced, or get into some races on the street, I can see keeping the TPI on it and saving some money.

 

If I get the HSR, will I have to change my MAF computer?

Also, how much do you think I can sell my TPI Plenum (red paint, without the throttlebody, ported to the 58mm TB, but not ported to the runners), the fuel rails - no injectors - my Edlebrock Hi-Flo runners, Edlebrock baseplate, Edlebrock aluminum center bolt heads with covers, and Crower roller cam (213/221 @.050 with .503/.525 gross lift)? I literally have less than 500 miles on all that stuff (and most of it was on the dyno).

 

How about another option, the FIRST TPI system. Larger diameter runners that are a little shorter would give you a little higher rpm with lots of low end torque. But for value you can't beat the HSR.

 

How about a third option: I set the car on fire and then jump off a bridge?

In all seriousness, I REALLY DON'T KNOW WHAT TO DO NOW. The Az Speed runners coupled with the AFR heads and the 222/234 cam swill likely make great torque and respectable HP, but at lower RPMs, while the HSR will make less torque, but more HP and run at a higher RPM. SO WHICH IS BEST - I HAVEN'T GOT A CLUE!!!

 

I had AZ Speed runners with a TPIS intake and it was really fun to drive around town... lots of low & mid-range torque. I then switched to the HSR and its less fun to drive around town.
I won't argue that the HSR makes more power up-top But you really just have to decide where in the power-band you will spend most of your time.

Hope this helps.

 

It does; I have Lingenfelter's book on modying small blocks and he repeatedly talks about the importance of building the engine to produce power in the rpm band that it spends most of its time - which is why I thought a good TPI would be best since I won't be at the drag track, ever. Lingenfelter liked the TPI over all other intakes - including the LT1 for street apps. In fact, I believe the LS motors all have the longer runners like the TPI used. So again - for street and freeway use is the TPI better???

 

If you are mostly interested up to 60 mph, go with the LTR, if you are interested from 60 on up, go with the HSR.
Also if you are going to set you and your car on fire and drive off a bridge, make sure to have someone video it for youtube.

 

I agree with redcorvette...

If you are only going to use it around town, I would stick with a LTR TPI solution. If you plan to take it to the track, race, etc I would go with a better flowing setup like HSR/Miniram. Based on what you've said, I think you would enjoy the LTR TPI solution.

Just my 2 cents

 

My wife's out shopping for a camera now.

 

I found this link on another site, http://www.superchevy.com/technical/...t_results.html

It is a 383, and the numbers seem very optimistic, but like the comp cams link you can see that you do give up some hp at the upper end but you still can get a decent amount out of a LTR. A 350 will move the peak hp and torque a little higher in the rpm range over a 383. From stop light to stop light a LTR rules, on the open highway a shorter runner intake rules.

 

Have you guys seen this article: http://www.hotrodlane.cc/injectionselection/page1.html

 

WOW RedCorvette, that article was eye-opening! Based on that, I think if I open up the Edlebrock baseplate, get the AZ Speed Runners, the AFR heads, the 222/234@.050 cam and port the plenum, I should be able to pull upto or beyond the 6000 RPM mark thus giving me the best of both worlds, right?

Does anyone know if I buy one of those base plates in the 'Quest for a better flowing TPI' article or have them do mine like that? Anyone know? And how much would it be?

 

Granted ; but you are not looking at the net numbers but the difference in how each intake works as shown by the graphs .The graphs would look similar on a 350; all TPI based intakes flat lining over 5K

Made no noticible difference to mine and actually helped at the track because it bled off some of the bottom end torque off making launching easier compared to the big tube setup.60ft times still within .1 of LTR

 

There is a shop here in Orange that will do you base plate like the one in that article.

I have had them do several...the cost $100 for welding $500 for porting.

Pm me if interested.

We have three cars in that article that have these #'s

370/410 (stick) RW
364/396 (stick) "
380/395 (auto) "

Burnout91 made 331/387 with the Edelbrock base (not welded and ported) just port matched and SLP runners (auto)

 

"The heads were sent to Extrude Hone for porting and finished up with a competition valve job."

Extrude honing on a set of SBC heads runs about $1200 without the valve work.Makes a set of aftermarket heads look very attractive

 

Last night I was checking EBay and found a company out in Arkansas that was selling a complete LT1 to L98 conversion, with fuel rails, chromed and ported, but without the TB or injectors for $500. What do you guys think about that?

In my research on all this stuff, it seems that the LT1 conversion works better than a miniram or HSR - if it bolts right up and I can use my own 58mm throttle body and ECM, would this be a good alternative to a hi-flowing TPI for overall performance, ie, good low end torque and higher RPM operations peak HP (with a 222/234 cam and AFR heads)?

 

i was deciding the same,i bought Lingelfelter's book and came with the
LPE219+AFR195+Super Ram proven combo.
its the best of both worlds,i call i a "mid length runner" setup.
Its good for the street and good for the track,why not a Super Ram ?

 

I got cash for the base plate bro.I started the same mistake ALONG time ago...I'm just going to do it anyway.Accel runners(Already had the SLP runners,they DON'T look anything like the pics on the inside)The Accels are the same crap as the SLP's inside without the small slit between the runners.I believe the AS&M runners to be BETTER quality and smoother.I can tell you ALL from first hand experience that my neighbors 383 Lingenfelter TPI was EVERYTHING you could ask for,and it ran a stock(ported)plenum,58mm throttlbody,big baseplate,and a gearvenders O.D... 208MPH top speed,10.79 quater(on the giggle gas) and STILL got 30mph going to the lake. Yeah he is an oldass man who owns a construction company,but that just shows you the possibilities of TPI. If you want to email me with your number,I'll call you about the specifics of what all I am willing to pick up,but to be honest..SUMMIT sells the Holley for CHEAP!!! I already have half the junk I need for the stocker tpi setup.

 

I would recommend the FIRST TPI with a XFI268 cam and a little porting to your existing Edelbrock heads. ECM tuning is also essential to meet your goals.

 

do you have the FIRST installed ? would love to see some numbers !
im considering it to try it out in the future

 

First of all, I want to thanks all you guys. The help you've provided has been amazing. I really appreciate all the posts and WHEN this thing is done (it was started in 2001), it will be in no small part because of all of your help and advice over the years.

So, to answer the last question, YES, I had the first set up installed for about 3 or 4 years but since I couldn't find anyone to dyno tune the computer, it just sat in the garage with fuel stabalizer in it - although I did turn it on and drive it around the block every few weeks so the new battery wouldn't die - which it did anyway (die-hard my ***).

Then, about 4 or 5 months ago, I got a spurr up my *** to finish this thing, so I talked to my Viper shop since they dyno tune high performance cars all day long and they said that they could tune mine so long as I got them the interface for an OBD I ECM. What'd that mean? It meant me spending $600 for a wide-band O2 sensor (which it turned out I didn't even need), and a complete ECM emulator set up from Moates.

So after I got all that stuff, I turned the car in and that was about 2 months ago. Once they tuned the car, it made 343 lb/ft of rear wheel torque at 3500 , but peak rwhp was only 243 at 4000 rpm!

Bear in mind, this is a car with a ported 58mm throttlebody; Edlebrock hi-flo runners, baseplate, performer aluminum heads and tubular exhaust (headers to tail pipe); forged diamond pistons/con rods running at 10.8:1 compression; knife edged Scat crank; Crower roller cam (213/221 @.050 with .503/.525 gross lift); Crower roller lifters/rockers; a t-5 with a 3.73:1 rearend; and now a custom dyno tune. So needless to say, the peak hp numbers were VERY disapointing!

At first we thought it was valve float since it pulled hard, then flattened out and died, but we sort of ruled that out; we then thought either the cam wasn't degreed properly by the IDIOT who first built the engine (we still don't know whether that's the problem) or maybe we should've ported the plenum to the runners (almost like having 8 little restrictor plates at the top of the runners now).

In either case, the shop thinks I should get better flowing heads a bigger cam and a mini-ram. I countered them with AFR heads, a bigger cam, but a set of AZ Speed Runners (ported to the plenum) instead of a mini-ram and now we're in a holding pattern until we figure out what to do; life sometime sucks

 

How much can life really suck when you have a Z06 & a Viper to take your mind off of the small stuff? LOL!

Bill

 

Hey ESB,so you took off the FIRST in favor of the Edelbrock setup ?
Any differences ?
Thanks !

ps : i would love to try every TPI intake and use my buttometer
and see how accurate it is ....if its really faster or track times are saying more than my
old fashioned way to measure it

 

YES it will. If you want higher hp but still good torque do HSR or miniram. HSR will fit under your hood. Stock motor mounts? clears better. There was 1 small spot I had to cut out under my hood (the bracing) to clear my HSR. No biggie. I think i have pics in here:

https://www.thirdgen.org/forums/alte...ealth-ram.html

Thing about long runner TPI vs short runner miniram type stuff is you may loose PEAK torque capability but the area under the curve throughout the rpm band will be greater so the car should be faster and more fun. Its a flatter torque curve with HSR/Miniram so the curve will look more like that LS6 vette you have and not peaky like TPI motors.

I have done the HSR swap on stock L98 and noticed the motor pull was different but much better after peak torque rpm which was in the mid 3000 rpm area. TPI felt good off the initial hit but quickly became boring. HSR held good power another 1000 rpms and really showed at the track, and became a fun car to drive around with the new found high rpm power.

The TPI mods done by the california guys making good numbers essentially create a single plane/miniram/hsr type motor but retain the TPI look. The shortened runners loose peak torque but gain torque everywhere else and with the increased rpm range, more power is made.

400 at the tires with a 355 motor is tough but can be doable with right setup and right tune. AFR 195's and a 230 deg cam would help and that setup benefits the most from HSR/MINIRAM.


EDIT: another option is the pro flo XT manifold from edlebrock. Similar to HSR but I believe it may fit abit better but cant confirm. I know HSR doesnt fit vettes but one guy has the pro flo xt on his C4 and it has room to clear the hood. ONLY problem is the LS1 throttle body has a high rise flange that sticks up above the intake, so if that hits you will have to find a way to flip the throttle body upside down or grind that flange off somehow. I believe the vette guy had the TB flipped.

 

True, but I miss my beloved Camaro that got me to where I can afford to nurture it back to health.

 

No; the Edlebrock set up was the first - the car was originally a 2.8 v6 auto (although I had it making about 260hp and beating 5.0 stangs with it back in the day - I love Chevies). Now I'm going to get the AFR heads and the 222/234 cam.

Today, I looked into how much it would cost to get the Edlebrock baseplate to flow 300cfm and it'll be $620! So, if I were to do that AND buy the AZ Speed runners, I'll be in the miniram cost territory and still unsure as to how it will do in the upper RPM bands - Because of that, I've now started looking into the HSR or the LT1 conversion to go with the bigger cam and AFR heads.

 

Thanks Orr89RocZ. I've already turned my attention to the HSR - overall it's a better deal and will probably get me what I'm looking for although not as pretty as a TPI I think.

As far as the motor mounts, this car was originally a 2.8 and so I maintained my crossmember and I have poly mounts - I don't think the engine sits higher. Although with the HSR, the triangular strut-tower brace will have to go on Ebay.

One question I have for you though, since you've done this: will my 58mm BBK/Edlebrock throttle body work with the HSR and will I be able to use the linkages and all that???? Or is that a whole new headache?

 

Should work fine. My stocker needed abit of clearancing to the linkage because it hit holley's fuel rail fitting. Grinder fixed that. My holley 58mm did not hit anything. It fit good. Others may or may not need some clearance depending on the actual linkage bracket they use. FWIW, mine used the 89+ style linkage as the 85-88 i think used a slightly different linkage bracket.

With poly mounts on my car the motor sat up a bit and did rub the hood in a spot even with the bracing cut out. Slight annoyance but oh well it made 400whp and didnt cost an arm and a leg like miniram.

 

The only advice i have is that the lt1 motor is pretty identicle to the tpi. The head flow numbers, cam specs, and the intakes are DIFFERENT. Take the tpi setup it has a runer length of up to 17 inches, the lt1 i believe is somewhere like 6? The TPIS miniram is a short runner 4inches so it increases rpm and horsepower and the gap it seems that you have with your 343/243 it may be able to make it go hallf way both ways, like 300/300. If you are putting afr heads on it and a new cam, might as well take it to the next level and go with the miniram no hood clearence issues. If you threw the intake on top of what combo you have set with the afrs, and that cam. You should be able to see a healthy 325horses and like 330 torque.

 

You don't think that I'll get those numbers from an LT1 conversion or the HSR (with a 222/234 cam and AFRs)?

 

I couldn't get the hood to close on my 92 Camaro with poly mounts and the HSR. I went to a 2 inch cowl because after I measured I saw I couldn't trim enough to fit the stock hood. But... I took the HSR off a wrecked 92 Z28 that did have the stock hood so it will depend on the car to some degree.

For the TB, I used the earlier style linkage for the 85 - 88 style cables and everything cleared the fuel rails just fine on the HSR. The later style linkage rubbed on the rails and would have required some clearancing. Fortunately the 58 mm TB I purchased came with both linkage sets and it was an easy swap.

 

Cool - that's what I have the 85-88 style cables and linkage; but now you got me worried about the hieght issue. How much was your 2" cowl hood - is it at least lighter than the stock hood? Do you think that with the 2" cowl you could fit a strut tower brace on it now along with your HSR?

 

The 2 inch cowl is definitely lighter than the stock hood. Your strut tower brace still won't fit though. The intake sits high enough to interfere with it.

 

Who needs a strut tower brace anyway? I've done everything else there is to do on that suspension - including Koni adjustables, lowering coils, subframes, wonder-bar, sways, panhard and poly bushings; so I guess I can give up the strut tower brace, right? After all, it's nothing more than just another needless expenditure that's now going into the toilet I'm really starting to hate this project.

How much was your hood anyway - it's the bolt on right?