Ok so here it goes. I have an 86 iroc. Specs below. I'm looking to get a tune on this car but the tuner guy is telling me some stuff I don't really believe. Looking for info/guidance. I would like to get 500hp out of this motor but not sure if that's attainable right now with my current build. Hoping with current build i can get 400. Tell me your thoughts.

First off the tuner said that with my injectors I can get no more than 240-250 horse out of them just because of the injectors. They are 24 lb injectors he is saying that for every pound you can expect roughly 10 horsepower. He's also telling me that my intake manifold and Runners will not support anything over 200 or 250.

I'm pretty damn good at Building engines. Diagnosing issues on engines. But when it comes to tuning and custom builds, I just don't have any experience.

Holley HP Efi ecu.
383 stroker motor.
Compucam 2050(I have detailed specs if it helps)
I'm not sure what heads are in it. However they have four bolts That hold down the valve cover and they are aluminum.
24 pound injectors.
Edelbrock hiflow baseplate 3861
Edelbrock hiflow runners 3865
Using stock air intake with k&n filters (I feel like this is already a good setup, why change it)

I have alot more data on the motor if it helps. The previous owner kept most of the receipts that I have scanned and saved to a Google drive account.

I would really appreciate input frok people that have experience with this stuff. Thanks!

 

The 24#hr are small for a 383. Here is a link to a good injector calculator.
http://www.megamanual.com/v22manual/minj.htm

 

24 lb can do well over 300 whp in the right setup

Tpi edelbrock runners and base un ported likely wont get much over 260-280 whp imo

If you can port and or siamese them some you can get over 280 and maybe 300 but you need good heads

No idea what heads you have makes it difficult to know.

And that cam is tiny and will not make the power you are after

 

So what intake manifold and Runners should I get to shoot for that 4 to 500 horsepower range? Also any suggestion for injectors?

 

If you want tpi i would try FIRST fuel injection systems

I would skip all that tho and go straight to a holley/weiand stealth ram if you can find one, a edelbrock profli xt ported out abit, or a miniram. Else a single plane victor efi type deal with a 90 deg elbow and lsx throttle body

Much better bang for buck. Rev to 6500, make 450-500 with ease on motor. 380-425 whp fairly easily with a good 195-200 cc head and 230 deg cam

 

Orr's right on the money.Just spend some time on reading Ten Times torque article On the TPI section of the forum.

 

I'm also running an Holley HP EFI. ...any reason not to tune it yourself? My set up is a little more aggressive than yours, and it self tuned wonderfully. I'm digging around for more, but it ran very without my tinkering!

I'm with these guys on the intake and injectors though. Bigger injectors. Better (at LEAST ported) intake.

 

Hey all sorry for the late response. Had some personal issues i had to deal with.

So i looked up the Holley stealth ram, looks like thats a whole system, around 3k and i would have to change my hood, Is that what your talking about. And the weiand stealth ram i found on amazon for about 450, but it looks like i would have hood clearance issues with it too.

I really like the stock hood on mine and would like to keep it. Is there an option i could go with and keep the stock look?

Forgive me for my ignorance here, i have been turning wrenches all my life but never done anything like this. Always just stock engine rebuilds and fixing cars here and there.

I appreciate all the input guys, Just please over explain if anything. Some of this is foreign to me. :-)

 

You can run stock ecm tpi stuff and make that power but you will need to learn tuning or have someone do it which is hard to find as not many do 80-90’s stuff anymore

 

I got someone who will do it, He just says with what i have right now i wont get much over 300. And if thats the case then i want to get the right parts before i tune it. Right now its just a self tune, it runs pretty good but i know it can be better.

 

If there is anyone out there who might be able to help me tune it better, maybe thats all i need.

If anyone is good at tuning the system i have i would be very appreciative.

Thanks!

 

The tpi part and the baby cam is limiting it and maybe the heads depending what you got

 

Ok, i get that. So you said the tpi part, meaning i need to change from the stock tpi to something else. Suggestions?

Same with the cam, you had mentioned "good 195-200 cc head and 230 deg cam" Any brand model you would suggest?

Thanks again.

 

You might want to look into dynamic efi ebl.

 

heres my combo that i recently did and produced around 275 to the rear tires which is probably around 340 at the motor .. fun street car

afr 180 heads , tpi big mouth intake ,as&m runners , ported stock plenum ,stock air intake , 27 pd injectors, dyno dons headers , stock type exhaust , lunati 219/228 5.35 lift , stock 350 block ,crank,rods and pistons .. 700r4 trans, stock ecm tuned by orr89rocz .. sounds like a combo like yours except the 33 more cubes ..

 

Before you guestimate what you think you can get out of the motor you need to find out what heads and cam you have.
If your going to stay with the edelbrock intake and runners they will need to be ported to the max to flow.
30# injectors to start with on the 383.
With the right heads and cam and with all the port work to the intake system and with the right tune you will get close to 500 ft pounds of torque but only close to 400hp.

 

If no budget go afr 195. Or chad speier profiler’s

More budget chad speiers flotek ported casting, 195 ish cc or so or the as cast profiler 195

Or more budget maybe brodix race rite Or dart shp 200’s, something in there

 

383 cubes making 500fwhp?
Stealth ram intake
58mm TB
AFR 210s
Cam 230+ duration .600lift 110-112 lsa
Atleast 36lb injectors
Good exhaust flow 1 3/4” headers with atleast 3.5” catback freeflow muffler

 

To the OP, I'm confused, do you HAVE the Holley system? You mentioned looking at it, then a day later you said you had a self tune?

Anyhow, just to touch on a few things. You can use your stock TPI, but there are limits as has been mentioned. On a 383 it's pretty restrictive. I've got a heavily cut/ported/welded aftermarket set up on my 383 and it's still done at 5200 RPM. It's no race winner, but man it's fun. I knew it when I built it, and it delivers what I wanted. Overall performance, stock hoods, and low budgets typically don't go together!

As for the Holley system itself, my goal was a system that would self-tune well enough to run well and get me to the cruise in, yet have enough support to allow me to learn and ask questions as I figure out how to put a performance tune together. It delivered in spades. Nothing but good things to say about the system.

 

As for the engine itself, definitely step up to 30 lb injectors. Maybe more depending on what you ultimately build.

The engine is a system and the heads, cam and intake all have to work together. A long tube runner (L.T.R.) intake system like a stock TPI (or your edelbrock set up) is relatively low flowing system. At lower RPMs the air is moving very fast so it makes a lot of torque, but as RPMs increase, it just can't flow enough to make big power. On a 383, those characteristics are exaggerated. My LTR is heavily modified, but it still won't impress you on the Dyno. It just...won't....flow....enough!!! ...but the modding helps, and.....I chose a relatively small (for a 383) 180cc head, and a relatively small Lunati voodoo cam coming in just a tad larger than the GM Hotcam. All those parts ultimately make my system a poor drag racer and a poor Dyno queen, but the torque down low is amazing. -Frankly, it's TOO amazing, lol, and my tires do NOT like me for building it. But it's fun, and it's what I wanted.

....you gotta figure out what your goals are before you pick parts. Nothing wrong with running what you have. -But if you're gonna start changing out parts, you need a plan.

 

i'm making 340 rwhp with a 6psi paxton with the edelbrock base and runners about 400 to the crank all on a stock 91 alum head vette 350