my friend who has an LT1 broke his rear end last year and he had flowmasters and an intake on... he just built back up the rear, and suprisingly enough the original gears were 2.73's when he bought it.. (or somethng in the 2's)... now he has 3.73's with a girdle and a huge trans fluid plate (or whatever he called it) and he just got a toggle switch put in to run the fans in between rounds? originally with the 2.?? he ran 14.3's, and he asked me what he should run now, and I guesstimated well into the late 13's and he acted really suprised? Is what I said accurate?

 

sounds about right,

 

Yeah the gears should get him into the 13's

 

I'll say 14 flat; 3 tenths from just a gear swap would be pretty good.
I'd like to get 3.73's myself, but I drive a lot and gas is expensive. That should probably put me well into the 12's.

 

If he was running 14.3 before I would also have to say he might 14.0. On the rare occasion a LT1 will see high 13's stock.

I had one LT1 with 3.23's and another with 2.73's which your buddy had, in equal conditions they ran almost identically. The one with 2.73's however had a very consistant 99mph trap speed since it shifted into 3rd gear five feet before the traps.

Just make sure he uses a programmer to make up for the gear swap or his speedo, ABS and shift points will be all messed up.

 

uh, we generaly average about .4 from a gear swap alone. some have gone .6 better on a gear swap, myself included. What "intake" does he have? What year LT1?

A 13.6 or 13.7 should be fair on a decent launch. He needs to get himself a real cat back and a good tune for the gears and few mods that he has. If I had to guess, I would say that he will best a 13.8 unless he is good at adapting to new parts rather fast.

What fan switch did he get? Probably not as good as the ones that I biuld




Just to compare. When I had a CAI, cat back, Tune, 4.11 gears and a good clutch, I was running 13.6 on street tires. But that was also through a 12 bolt and a very heavy 3.5" steel Denny's Drive shaft. I killed about .2 due to that. Granted him being an auto would negate some of that, hence my guess of a 13.6.