does anybody have a copy of that article they could post? i think it got posted a while ago either on here or on patricks site but it wasnt very good quality. its the article where they put a cam, heads and throttle body on an LT1 and got like over 400 horsepower. i think it was in CHP magazine? can any body help me out?

 

I dont.....but I would like to read it. I cant believe that they got 400 by doing that. Probably no possible.

I had posted a while back (6-9 months) about the GM upgrade....kit was like 2200 and included new heads, intakes, gaskets, hot cam, and roller rockers (I think-----not sure about the hot cam kit). But - everyone told me I could do better just by doing the cam and RR and doing heads through a local machine shop.

Bottom line - I'm still 5-8 yrs away from a Z06 - so I want to take my LT1 to 405 at the crank...just so I can say I am over 400. Looking for any easy naturally aspirated way to do that. But - I want to do it for only 2 grand.... and I dont think that is possible.

:lurk:

 

This is an easy one. Pick up a copy of Summit Racing Equipment Catalog and they have the entire convertion kit for $2289.95 plus shipping & handling. It has Heads, intake, roller rockers, Hot cam, and gaskets. Says 425 HP from your old LT1. It's all GM Performance Parts. BUT, for 92 &93s you need to go with a 94-95 fuel rail and they ain't cheap. Most guys figure it would be better to have your heads worked on and find a better cam. The fancy red intake doesn't give you much.

 

but a LT4 has only 330, right (I know I know - it is an UNDERRATED 330)

how do we get to 425

 

BrentDev
i have a copy of the article someone posted a long time ago it is just really bad quality. if you give me your email i can email it to you. i just wanted to see it clearer so i can actually read all the small print
they did it with a lt1 putting lt4 heads hotcam 52mm tb and headers and roller rockers ect. i have an lt4 to start with so i think i may be able to do this conversion and get this kind of power a lot cheaper than the lt1 guys since i dont have to buy heads ect.
if anyone has a good copy of the article or knows how to find it please let me know

 

Yes 330hp, but this is a conversion with the hot cam.A local speed shop has done a few of these and swears buy them.You still have to get your computer reprogramed.But with all that and a good set of long tube headers and exhaust, you should have no problem pushing 425+ at the crank. :chevy

 

If you're like me and you're thinking of this kind of mod, here is another link to explore: http://www.moreperformanceinc.com look for the "packages" for LT1 and LT4s. They are a little expensive, but they do great work. We have two C5s in our club that push over 600 HP with superchargers or juice. They have a "top end package" that has heads, roller rockers, cam, 52 mm TB, and computer programming for around $3500 or so.

Just checked the site and corrected the price. :banghead:


[Modified by Strick, 8:23 PM 12/30/2003]

 

I would sure like to know more about this GM Performance package that Summit is promoting.

These can not possibly be stock LT4 heads/intake since then all I would need is an LT4 hotcam to upgrade my stock LT4 to 425hp and I know that is not possible.

I really think their add is incorrect!!!!

 

I would have to agree with you. Common sense and logic dictate that the hotcam is not going to shoot you to 425 at the crank. I think in order to get the HP you're looking for, you'll have to have your stock LT4 heads and intake ported.
CNC Heads in FL does great work, but you'll pay about $2,100.00 to get your heads/intake ported (Stage III). Talk to Pete about a custom cam for your setup. They're a CompCams partner so he can get exactly what you need.
Throw on a set of roller rockers and open up your exhaust - then you'll be looking at 425hp. :)

I figure about $2,500-$2,800 for the porting/parts if you do the work yourself...

 

I'm running a CNC Cylinder Heads LT1 heads/cam package. My car is currently putting out 355 rwhp, and hope to have more when the long tubes are installed in early Feb. Also, I paid $1750 for the Stage III head work and the camshaft.

 

This is exactly the package I got as well. The only difference is that the cam I went with is 224/230. It's good to see you putting out that kind of power - I hope that I can as well (install to come soon). :)

 

wonder what kind of power would come from just cleaning up the heads (gasket match, polish the bowls) plus RR, Hot Cam, and Headers. I already have a catback.

Would a bigger TB be needed? Obviously a new chip would be needed.

I'm looking for 400 on the cheap! :lol: :lol: :lol: :lol:

 

does anybody know how to post pics? i have the pics of the article. its a little fuzzy so its not the easiest to read but if someody will give me an email that can post them i will glady send them

 

Go ahead and send them over - I'll post 'em for ya.

cprgmr@new.rr.com

 

BrentDev
That sounds kinda like what they did in the article. i know i plan to do a lot very simalar to this here in a little over a year im going to "rebuild" my top end. I have no idea how much hp to expect but i already know exactly what im going to do. since i already have the LT4 to start out with it gives me a good platform. i plan to take off the heads and polish them, take off the intake manifold and do some port matching as well as replace all gaskets i can. im going with the hotcam, im having my stock throttle body bored out to 52mm, new studs, springs and perhaps roller rockers, timing chain, adding LT headers, no cats, and a bunch of little things that are somewhat maintenance like NGK plugs, MSD wires, new fuel pump, MSD 6AL, change tranny and diff fluid. I know I will see maximum benefits from this build if i purchase the LT4 edit. And i most likely will just not sure if i will do it at the same time since it costs like over 500 bucks(but well wroth it in my opinion) I am hoping with all of this and once i get the LT4 edit i will be pushing over 400 by a bit(at the crank) I have no idea how much power just polishing the heads will give you but if nothing else it will help them get back all their origanal power. i have quite a few miles on my LT4!

 

I'm surprised no one has done this conversion and has dyno results.This GM package has been around for years.I've seen it advertised in Summit as well as Jim Pace Chevy, GM performance parts catoluge and a slew of other GM dealerships that push performance parts.Every time it's advertised as 425+ hp.It might be a bit optimistic, but who am I to argue with GM. :chevy

 

I am happy to donate my car as a test platform.

There is a dyno right down the street from me.

GMPP - send me the kit. I'll pay to have it installed, and I'll pay to have it dynoed on my 93. :D

 

Of course - I then keep the kit.

 

:rofl:

 

I've done the LT1/LT4 Hotcam conversion on my '96. Through the stock manifolds it put down 316RWHP with the torque converter unlocked. Add in a typical 10RWHP with a locked converter and we've got 326RWHP through an automatic. This equates to about 385FWHP (using 18% drivetrain loss).

With longtube headers (and proper tuning) I wouldn't think that north of 400 would be that tough.

I dyno'd at the same place and time as STL94LT1 (a very sweet car BTW Mike). As you can see in his sig, he's got shorty headers and an electric water pump. Mike's cam is a little shorter on duration than the Hotcam but has a bit more lift. I imagine his heads flow a bit better than stock LT4 heads as well.

Overall, Mike (STL94LT1) has put together a very nice package. He's gotten excellent numbers from a car that seems to idle like stock.

For a better comparison to STL94LT1's numbers, 96GS#007's LT4 with a very similar setup (same shorty headers, electric waterpump and 6 speed naturally) plus a Hotcam put up 340RWHP on the same dyno, same day. That's about an even 400hp at the crank. With longtubes I'd think that number could increase to close to 425FWHP.

Overall, there are a lot of choices which will give you your desired horsepower at your price point.

I chose the "all GM stuff" because I knew it would all fit together and would have acceptable quality. I don't regret it a bit. I spin the engine to 6500+rpm regularly and often have extra fun with a 100hp shot of nitrous.