Looking to rebuild/mod a 95 LT1 engine. Planning on a little nitrous but no forced induction. Low end power not important, I need plenty of hp in the higher revs 3-6k to match my application and weight (3000lbs).

Thinking about the LT4 heads, intake and "hotcam" valvetrain, with long tube headers and possibly some port work. Any Ideas?

Its going into a project car, and I am looking for about 400-425hp (without NOS) with a fair idle.

The project car is manual trans.

Thanks..........RAY

 

First off, dont do the LT4 conversion kit... its a waste of money. If you want LT4 heads, then buy the heads and get them ported to flow close to 300 cfm. If you arent looking to go over 425 rwhp, then dont worry about the LT4 heads, just sent your LT1 castings to AI or Lloyd Elliott (do a search to find more info), they can work miracles on stock heads. Then get a nice cam to match the heads.

If you want 400 fwhp, then that is simple to do on stock unported heads. 400 to the wheels cant really be done on unported stock castings.

Headers i would recomend Pacesetter LT's or Jet Hots. Get them coated too, its worth it.

Cam... thats up to you, but you can always go with a cc306 and it will put you near 400 fwhp with standard boltons (headers, intake, TB, exhaust, tune....). XE Comp cams are also very nice off the shelf grinds.

Send the PCM to www.madz28.com or www.pcmforless.com to get it tuned for your specific setup, they both do good work for cheap.

If you plan on spraying TNT or NX makes good kits, but everybody has their prefrence. 150 shot would be the most i would spray on stock pistons. I prefer wet nitrous (less strain on injectors).

Good Luck
-Stu

 

Thanks STU, I will check into this. As far as spray, yes I am planning on a wet kit, dry kits scare me..
Headers will be custom made (no choice) for my application.

So, you think 425rwhp should be pretty easy with ported stock castings?

Thanks.....RAY

 

I wouldnt say it's "easy" but it has been done by quite a few people. To get to 425 rwhp, you would need heads that flow close to 270 cfm with good midlift #'s too. Most reputable shops can port out a LT1 casting pretty well because they are only slightly different than SBC heads. There have been people that can hit 415+ with a cc306 or gm 847 cam, but a custom cam will net you a few more ponies. Id say 450 NA rwhp is the most that a streetable LT1 on stock cubes can really go without getting REALLY expensive.

From what ive seen, there are multiple stages of power that an LT1 can achieve. It gets exponentially more expensive as you get faster. 350 NA hp can usually be done with a good cam and bolt ons. 390 NA hp takes some head work. 425-450 NA hp takes bigger valved heads and better porting. 500+ NA hp takes big cams, AFR or ported LT4 heads, and forged internals; 383 or 396 doesnt hurt either.

As far as the 10 bolt goes, you can put all the power in the world through it on stock tires and suspension. It wont hurt it until you launch it hard or get sticky tires.

Just something to keep in mind,
-Stu