ignoring exhaust and what not, was the motor itself any different from the f-body lt1? I hear word the F-body lt1 was underated much like the ls1.

 

Vette motor has 4 bolt mains, Fbody engine has 2 bolt. And less restrictive intake/exhaust i believe. Otherwise they are basically the same engine. And they dont seem to be underated like hte ls1's were. If you look at peoples dyno #'s on here M6 Lt1's can be around 250hp at the rear wheels which is about right with the engines 275/285hp.

 

Actually if you do the math....Its not...With a M6 at 275 * .16-.18 drivetrain loss:

(275 * .16 = 44) (275 - 44 = 231 rwhp)

(275 * .18 = 49.5) (275 - 49.5 = 225.5 rwhp)

now lets say they were underated and really push 300 at the crank:

(300 * .16 = 48) (300 - 48 = 252 rwhp)

(300 * .18 = 54) (300 - 54 = 246 rwhp)

I think its safe to say GM underated these vehicles.

 

everybody underrates their vehicles

 

OK, thanks for that useful piece of information. That wasn't the question at hand

 

The cam in the Corvette LT1 was a bit different in most years. If you want, I can dig up the specs. A very small difference though. Other than the 4-bolt mains that's the only difference I am aware of.

Rich Krause

 

Well, Mazda overrates their vehicles. I hear they had to lower the advertised hp for the rx-8 and even offer a refund to previous buyers because the numbers were too low.

I also think the lt1 is underrated, but only slightly, not as much as the ls1 in the f-bodies. LT-1 f-bodies should be at over 300 at the crank with a good intake and exhaust.

The only real difference is that the Vette LT-1s have four bolt mains.

 

http://www.automotiverebuilder.com/ar/ar99928.htm

There it is, I think it's probably been posted 20 times or so. Cam specs are only different when comparing the aluminum to iron heads. There are some very slight differences between the years.

 

Exactly what I wanted to hear guys, this holds true, I may see more rwhp then I expected from my car. The way im calculating it:

300 to start with + 15-20 from the headers, another 20-25 from the RR arms
+ 13 from Ions 13 hp gaurantee.

Im seeing gross hp at a maximum possibilty of:

(300 + 20 + 25 + 13 = 358 flywheel hp)

Add the drivetrain loss of 16%:

drivetrain calculation using: (300 * .16 = 44)


(358 - 44 = 314 rwhp)

The reason its -44 rather than *.16 is just because your horsepower goes up does not mean it takes more power to move your drivetrain.

Now a realist possiblity would be:

(300 + 15 + 20 + 13 = 348 flywheel hp)

(348 - 44 = 304 rwhp)

I think that is reasonable. Thank you for your information.

 

I dont think RR's are gonna give you a 25 hp increase with a stock motor.

 

Why not? Thats just about .30 more lift.

 

Car Craft did an LT1 buildup guide a while back and said to expect 12-17 at the wheels with 1.6 rrs.

 

If you looked, thats exactly what i'll get, thats flywheel horsepower I added for, infact, I was being reasonably pestimistic.