383 Vortec TPI Dyno Results (and questions) - Page 2 - Aftermarket Product Review - Third Generation F-Body Message Boards

03-17-2002, 11:24 PM

My Cranes are 1.5's and my Vortec's do not have the elongated pushrod hole. If I went 1.6's I'd exceed the lift limit of the springs, .550, so I stayed with 1.5's and in a recent test by GMHTP they found no real improvement with the 1.6's.

Mike Crews · 03-18-2002, 06:22 PM

Thanks for the reply FlashGTA. With the LPE 74211 cam and 1.6s on the intake. my lift will be .533 (I'm staying at .525 on the exhaust with 1.5s).

Just FYI, I was able to use the 1.6 roller tips on the vortecs without the pushrod hitting the head. It was close, but they worked. I put some red machinst dye on the pushrods, installed the rockers, turned the motor over with the starter, then pulled the pushrods out to inspect them. None of them are rubbng, so I'm OK.

I've almost got the car back together. So, weather permitting, my dyno run for Friday is looking good.

Later, Mike...........

1bad91Z · 03-18-2002, 06:26 PM

Badass! That should put you over the 300 ponies at the rear mark. Looking forward to the dyno results!

Mike

steve8586iroc · 03-18-2002, 09:14 PM

Mike, is it possible you could be leaning out on the top end a little. Thats a lot of cubes to feeding at or above 5k with 24lb injectors. Your going to have to retune it for the new runners anyway so why not get some 30lb injectors and see what a little more fuel will do.

Steve

03-18-2002, 10:52 PM

Glad to hear no interference problems. I will anxiously await your results.

drive it · 03-19-2002, 12:11 PM

Quote:

Originally posted by MikeH
Very Nice setup Mike, I recently got my new setup running and have been very happy with it so far. I think what you are finding out as I did. This is the typical TPI curve, the horsepower peak looks like the horizon of Kansas.

TPI was made for midrange torque/horsepower, not topend. Makes for a really fun street car, enjoy it!

OK, Question for Mike H-I see you have a 406 with a SR. I currently have a 406, trick flow 23deg. heads; with siam. runners that I'm pulling off for a SR. My dyno with the siam. runners also was like Mike Crews-flat hp curve. With your SR does that help? Or is your hp curve still flat? I'm sure hoping it does, so as to make the SR worth the $ and time!!! Right now it just flattens from about 4000rpm to 5200rpm with the most being 290rwhp. I'm sure hoping it'll pull up to 5600rpm after the SR.
And Mike Crews-please keep us updated-Thanks.

dnovotny · 03-19-2002, 01:01 PM

I've been studying combos and setups for a long time. Based upon several peoples numbers posted here, the intake ISN'T whats limiting your performance. Several people here have run the SS setup, and run low twelves at 107-108 mph on a 350! That mph isn't lacking hp or rpm, thats what most stock LS1s trap for mph.

Also, if you look at various magazine comparos like TPIS, a SS was only down about 20-30 hp on a 383 versus a SuperRam (using the same cam and heads). These engines dynoed around 425-450 hp (flywheel) on AFR heads.

I've got to believe that your real limiter are the heads. I've never seen very good results with TFS, and Vortecs aren't as impressive as I expected (but they're great bang for the buck). But with AFR heads, one normally sees over 1hp/ci even with long tube runners. With the right cam, and AFR heads, one should get a hp peak at about 5250 rpm, with around 400-430 flywheel hp with a 383.

Later, Dave '91 GTA, '91 T/A, '01 WS6 T/A

GofasterFirebird · 03-19-2002, 02:56 PM

dnovotny, what do you mean by "ss"??

dnovotny · 03-19-2002, 03:16 PM

SS stands for semi-siamesed runners. AS+M SS runners are the ones I'm referring to that yielded the low 12s and 107-108 with a 350. A lot of people use SLP runners, but unported and un-extrude honed, these runners are down at least 25 hp almost across the board with the same cam and heads on a 383 vs. AS+M.

Mike Crews · 03-19-2002, 08:15 PM

Steve8586iroc,I don't think that I'm leaning out at higher rpms because the air to fuel ratio on the dyno hung right around 12.5:1 for the entire run (all the way to 5600). That's right where it should be. Plus, all the part throttle programming done on my chip has my block learn values right at 128. Actually, on my second dyno run, I dropped the fuel pressure 1/2 pound, and picked up about 6 rwp, and 11 ft/lbs of rwtq. So there is no fuel problem.

Actually, I don't really think that I have any "problems" at all. The car is running great as is (for what it is - a vortec LTR 383). I'm just trying to wring every bit I can get out of this setup.

However, I do tend to agree with dnovotny on the point about the heads. I'm positive that I would make a good more power with the AFR heads, but I bought the vortecs instead to save a little cash, plus they look stock on the car. Oh well...........

Later Guys, Mike.

03-19-2002, 08:47 PM

Well, not to burst your bubble Dnovotny but I disagree. I know desktop dyno isn't the best but my ported vortec results are almost exactly the same as AFR 190's. Within 5 HP. Also if it were airflow limited by the heads you would not see a flat horsepower curve but one that drops off dramatically, as the RPM goes up you HAVE to supply more mixture or power goes down. The flatness is due to the very long intake runner tract, plain and simple.

dnovotny · 03-19-2002, 09:43 PM

89raptor, not to burst your bubble, but I know that the flat power curve is due to LTRs. But, there have been many setups both in mags and on the street that get close to 1hp/ci or more. How do you explain the low dyno numbers when the intake is the same, and the cam is similar. The difference normally lies in the heads.

I mentioned SS runners because with those, you pick up a considerable amount of higher rpm breathing.

Here's a comparo at a couple of rpms from Hot Rod magazine from over 10 years ago, so this info has been around for a long time (same AFR heads/cam for each setup, 383ci):

LTR SS Superram

3000 rpms 251 241 228
3500 324 301 289
4000 380 356 349
4500 397 402 392
5000 394 421 431
5500 410 427 445
6000 418 417 432

If you notice, there is a first harmonic and second harmonic type of horsepower peak with the LTRs. First at around 4750 (the one we're all familiar with), and a second at around 6000. I've only seen this on AFR heads, I believe the 195 cc intake runners help with the higher rpm power along with having the best flow numbers at higher lifts. You quote desktop dyno, I quote real dyno numbers. Also, I'd love to know how a head that flows 10% less on the intake side, and 20% less on the exhaust makes the same power.

And because I'm sure you think the numbers above are a fluke, Chevy Action in the same year did a similar comparo with similar numbers. I normally don't post any responses because there are always people out there who don't know much, but think they do. Myself and several others still can't debunk the belief that the sheet-metal for t-top cars is thicker than the hardtops. Several of us own both, and have actually measured the thickness and found no difference, but the same people always say I've heard the sheet-metal is thicker for the t-top cars. Ok.

Later, Dave

traumatech · 03-20-2002, 07:02 AM

Hey Mike Crews--sorry abouy just jumping in on your thread here. I've been following it for awhile, because you've done pretty much the same thing that I've been wanting to do to my '88 SC. My name over there doesn't show a whole lot of posts, but I've spent countless hours on this board trying to learn what I need to do to make this engine. My goal is to beat my Dad's '85 Crossfire (with a custom chassis, suspension, and running slicks) on the autocross field. To do that, I need the handling from something like the Spohn setup, and the quick power from a 383. What's holding me back is budget, which is why a vortec LTR sounded pretty good to me.

I had a couple of questions, though, if you don't mind. Are you using a MAF or speed density. I didn't notice that anywhere, but I may have missed it. I know that the MAF will let me do whatever I want to the block, whereas with the MAP, I have to watch my cam and make sure I keep vacuum. But with the MAF, even with screens removed, will it flow enough to feed a hungry 383? Or if you went speed density, how much more room do you have to go up on the cam before you get too much for the LTR and not enough vacuum. I guess at higher rpm's you've got vacuum, but is it the right amount for the chip to compensate, given that your flow is just a little short of what the ci's really want?

Sorry for the long reply. Just searching through this board has given me big jumps on what to do and how to do it. Thanks again.

03-20-2002, 08:08 AM

Dave, I've been racing now for 20 years, building engines and seeing them built. I get tired of hearing the old, "my heads flow better than yours" arguement as the end all to get all. It's all about making power and the Vortec's have the most efficient combustion chamber/port of any 2 valve pushrod head other than the LS1's. Why do you think Edelbrock copied the Vortec and Fastburn heads. It's the long runner length causing the flat horsepower curve not the heads. Why do you think time after time after time Vortec headed engines make a lot more power than predicted? It's all about combustion efficiency getting every last BTU out of the mixture and turning that into mechanical energy and a cast iron head will always be better at that than an aluminum head of duplicate design and the Vortec's are very good at it. It's easy to port a head and make it flow better, it's much more difficult to make more power, ask any racing engine builder why they spend 1000's of hours on cylinder heads. They aren't looking for 10 more CFM, they are looking for 10 more HP, that means efficiency and flow, not just flow.

Mike, it's not the heads, it's the long runner length. Sorry for going off like this, but I'm tired of hearing people rail on the Vortec's because they are cheap, they are great heads.

dnovotny · 03-20-2002, 02:26 PM

89Raptor, did you even look at those dyno numbers. The best comparison of intakes is with the same heads/cam combo. Did I deceive when I said the SS is only down about 20-30 hp at the top end versus SuperRam. No, I didn't. Also, if you look at peak hp with the LTR, that was around 410-420hp. Isn't that more than 1hp/ci. Yep, it is. rwhp would be around 360-380. With a LTR setup, the Vortecs are pulling around 280. Since both intakes are LTR, and the cam they used was a 215/225 grind, what's the main difference? Heads, you can argue all you want, but facts are facts. And because you don't like these facts, you ignore them.

Mike, you're running darn good times. I'm curious how much you'll pick up with the SS runners.

Later, Dave '91 GTA, '91 T/A, '01 WS6 T/A

1bad91Z · 03-20-2002, 03:33 PM

Look, if you guys want some real pointers, talk to Brian at Scoggin-Dickey performance. He built a 350 with Iron Vortec heads that made 360hp and that was with the STOCK chip. Thats right, that much power with out computer tuning! He even ran 24lb injectors with the stock chip. To compensate for having too much fuel, he dropped the fuel pressure to a low 31lbs. With a programed chip, he should see more power and will be able to crank up the pressure back to 46-48lbs. He should be able to help you guys out when it comes to Vortec headed TPI motors.

Mike

03-21-2002, 03:20 AM

Dave, what do your posted dyno results have to do with Mike's Vortec motor? Nothing. You are trying to use a magazine test that didn't include different heads to Mikes. You are trying to say his combo makes less power than the magazines when their can be numerous reasons why, including the differences between Flywheel HP and RWHP. You are trying to compare it without talking about cams or compression ratio or exhaust systems or total intake tract length and restrictions.
You chose to degrade the Vortec's and TFS and praise the AFR's with no real proof that his engine is limited by his Vortec heads. Yes, I believe that the AFR's are capable of making more power, but the Vortecs are capable of making 500 HP basically stock and more with some exhaust port work. With his current engine I don't see how he is limited by the heads, he hasn't reached the flow or performance limit of them.
But I'm sure you still think I'm one of those guys that doesn't know much, but thinks he does. Not to say I don't have a lot to learn, I do, and I learn a lot from the members on this site and others. But, let me know when you want to talk about cam timing events and how they affect cylinder filling, cylinder pressure, scavenging and efficiency. Or maybe you'd like to discuss how swirl and turbulence truly effects the power output of an engine and the efficiency and exhaust emissions and why that is. Or one of my personal favorites how thermal efficiency in an engine translates into power. But probably not. I'm sure you are a very learned person, and your posts shows you to be very knowledgeable and well read. But facts are facts, the laws of physics, engine design, power potential and true power don't change for AFR or Vortec heads.
I'm going to end my discussion on this as I think it's going nowhere, and I don't think anyone really cares.

I want to see what Mike's car does on the dyno, like everyone else.

Mike Crews · 03-21-2002, 07:48 PM

Hey Guys,

Lots of "lively" discussion on this thread I see. Anyway, I finally got the AS&M SS runners and 1.6 intake roller tips installed, and the car is running. Going to the dyno tomorrow, I'll post the results.

Traumatech, I'm running a MAF setup, and I don't think that I'm having any flow problems. I'll hook up my Tech 1 and do WOT run on the way to work tomorrow morning and get a WOT MAF gps reading from my car for you. The max for a MAF is 255 gps. I really don't know what my car is pulling at WOT, but I'll post that number for you tomorrow night.

Short on time tonight so I've got to go. If for some reason my car's hp and tq numbers go down (please say it isn't so) due to my recent mods, I'll just DRINK HEAVILY tomorrow night insted of posting anything (j/k).

Later, Mike.....

traumatech · 03-21-2002, 09:10 PM

Thanks for the info. Did you take the screen out of your MAF? Can't wait to see the numbers. Later.

dnovotny · 03-21-2002, 09:59 PM

Here's a recent link from one guy that easily made it into the 12s with AFR heads and SS runners. He also lists his cam in the thread, and he has his latest times listed with the miniram. Look for Traxion. Note that this is a 350.

Proven combo (not just in mags):

http://www.thirdgen.org/techbb2/show...threadid=92798

Later, Dave

P.S. Its true I don't design the fastest engines every day, but I do design the fastest micro-processors every day.

vaper · 03-22-2002, 03:37 PM

Hey Mike, I'm from Greenville S.C. I've been following your post
hope you can help me where do u race at i have a 1990 gta that i just put my moter in trying to get it tuned up if u can help i would apreciate it its 350 bored 40 over 6" rods srp pistons dart iron eagle heads ported & polished 200 cc runners 2.20 1.60 valves
ultradyne cam 288/296 dur. @.50 is 223int.231exh. lobe is 112 .530 int. .552 exh.w 1.5 rockers but i'm using 1.6 rockers the cam was degreed 6 adv. slp runners ported ported intake tpis intake 24 pounds lt1 injectors set @42 pounds right now the car is running rich havn't set timming yet hard to idle has the 350 chip in it for now how is your custom chip doing? i hope to get it running for the f-body gathering in may & june thanks VAPER...

03-22-2002, 07:39 PM

Dave, the link doesn't work. I'm not arguing the AFR's aren't good heads, just that Mike's engine is not limited by his Vortec heads.

I design the fastest way around any Mustang or *****, just gotta get more traction.

dnovotny · 03-22-2002, 07:58 PM

Sorry, lets try again with this link:

http://www.thirdgen.org/techbb2/show...threadid=92798 (What LTR setups have gotten you into the 12s???)

I've never been very good at using the technology I help design.

Later, Dave

Mike Crews · 03-22-2002, 08:22 PM

Hey Guys,

Well good news from the dyno run today. My new peak numbers are 293 hp and 415 tq (old #s 283/406). That doesn't sound like much of an increase when you are talking only about peak numbers, but my curves tell a good story. I was initially a little displeased until I started to really look at the dyno curves (still not over 300 rwhp, dang it). I picked up 10- 15 ft/lbs of tq across my entire tq curve from 3250 - 6000 rpm. On the hp side, I picked up 10 hp from 3250 - 4750, and 20 hp from 4750 - 6000. My air/fuel ratio was pretty much perfect at 13.2 for both my dyno runs.

The car drives like a different car, and pulls like no other on the big end. It picks up speed like my ZR1 (only until about 120). It is obviously breathing a bit better now, and the SS runners worked exactly as advertised, as I picked up 20 rwhp at higher rpms (and gained tq as well). I'm hoping to see my mph over 110 tomorrow night at the track, and my ET should drop into the 12.3 - 12.4 range (I hope, I hope). I'll post my track numbers probably Sunday sometime.

Traumatech, I running a "ported" MAF with the screens and heat sinks removed. MY WOT run this morning gave me a MAF gps reading of 210 gps (against a max of 255), so I'm not MAF flow limited.

Vaper, I'd love to help you out, but I consider myself a novice at this stuff. I'm learning as I go. If you have some specific questions for me, I can offer you my opinion. I'm not really qualified to address the general, big picture issue of "tuning" your new combo. I will say that I think your cam is HUGE (288/296) for a fuel injected car, and I would expect you to have some difficulty getting it not to run rich. My chip is doing great, although I had just finished geting it dialed in before I did all these changes, now my idle needs a little work.

Later, Mike.........

traumatech · 03-22-2002, 09:28 PM

Nice to see the numbers improve. Had a couple more questions. Where did you buy your stuff--esp the intake, runners, and cam. I've been looking for good deals, but being a novice myself, I'm looking for some customer support. Thanks, and good luck at the track!

Mike Crews · 03-23-2002, 08:07 AM

Hey Traumatech,

Let' see. First off, there's no such thing as cheap when it comes to fuel injection aftermarket parts, unless you catch a good deal on something used. I bought my intake from SDPC (obviously) for about $399, and you can get the non-vortec Edelbrock manifold (p/n 3960) from several differnet places like Jegs or Summit (I think) for about the same price, maybe a little less. The runners I just bought from Arizona Speed & Marine (the semi-siamesed ones) are - brace yourself - $475. The non semi-siamesed AS&M are $375. A lot of people like the SLP runners also, and they can be had from Summit for $269. I had a set of these and sold them. I bought my cam from Lingenfelter - personal preference. Cam selection is a tough job and can get complicated. It's also a "hotly debated" topic on the board. I have always liked the GMPP ZZ3/4 cam ($179 from GM), and I almost bought it for my car but went LPE instead. The LT4 Hot Cam is popular too, as it is also around $180 from GM. Do some searches on the board for cams, and you can get a lot of personal "testimoines" about different cams. SLP also makes several TPI cams, and TPIS also - check their websites. There are hunderds of cams out there for every application.

I don't know what you mean by customer support, but I wouldn't expect much from any of the guys that I have listed above. They're all happy to take your money, but they won't be a lot of help with the kinds of questions that you're going to have. You had better do your own homework, and then call for any clarification that might be required. In defense of "them", it's just not possible for them to really answer a lot of the kinds of questions that you might ask them, there are just too many unknown variables. For example, the TPIS guys are always very helpful, and will spend a lot of time on the phone answering your questions (NOT an 800 #, so you are paying to talk to them), but all of their anwers are directed towards their own products (and they cost $$$$$). That's just my own opinion.

There a A LOT of choices out there for induction parts. Good luck on your journey. Just take your time, use the boards, pick the stuff that you like, have fun with it, and dont' take any crap from anybody.

By the way, I am selling the set of AS&M LTR runners that I just took off my car, if you are interested. They are only six months old, they look like new, and come packaged as new. They include the orignal box, a new (not used) AS&M gasket set, all required bolts (only 4), instructions, and even the AS&M sticker. I have to have $300 for them, as I just paid $375 6 months ago (like i said, unfortunately none of this stuff is cheap). Someone has already expressed an interest in these, and he said he was going to buy them, so they may be sold. However, I have not heard from him for a while. If I don't hear anything from him in the next few days, I'll put the runners on the "open market". Just let me know.

Looks like good weather for the track tonight. Later, Mike.......

HiTech5 · 03-23-2002, 10:32 AM

Mike - I like the approach that you took with your motor. In the end it all comes down to what makes you happy. If the guys that replied could feel what kind of midrange torque that a long runner/big cube motor gives, they wouldn't be so negative. The thing is, once you post something, opinions are like a--holes, everyone's got one.

When I had my 355, I had pretty much the same combo as you with the exception of the heads. I very much enjoyed driving the car with that set up.

Good luck!

www.geocities.com/dzperf

Mike Crews · 03-23-2002, 10:45 AM

Hey HiTech5,

Thanks so much for the kind words. You're right about driving this thing - it's a lot of fun. That's specifically what I built it for - everyday driving fun. Of course, I plan on having "fun" at the track tonight also.

Thanks Again, See Ya' - Mike.......

03-23-2002, 02:30 PM

Mike, great to hear the results were so positive. Doesn't sound like you were limited by your heads, no surprise to me, I never thought you were. I might have missed it earlier, are you burning your own chips? Okay found it Street and Performance Chip, never mind!