I'm currently building a twin turbo 408, and I am trying to get it in and out of the RPMs real quick. Almost like a pro street kinda rev.

Does anyone have any thoughts on how to get a snappy LS1? Also, I am trying to avoid a HUGE cam, because it is going to be a daily driven turbo car.

4.030" Bore, 4.00" Stroke, TH400 auto (have yet to pick a stall).

Any thoughts on this would be great.
Thanks for your help.

 

aluminum flywheel helps greatly to get quick revs.

 

Thanks for the advice, but the car is an automatic. Probly should've mentioned that. I'll edit the post. Thanks.

 

Dosent matter how fast the motor revs, just matters how much power it makes. How it revs with no load shouldnt matter.

 

Dude Pro street revs are my favorite!



What is a pro street rev again?

 

LOL...
Kinda like this..except a lot tamer, because it's a street car. Haha
Now...I know this car has a HUGE cam.

Pro Street sound

This is a bit exagerrated compare to the sound I'm lookin' for.
I'm just trying to avoid how slow most LS1s come back down to idle after being revved. The quick drops in RPMs are the ultimate sound of power...I love it.

 

It is my understanding that the quick return to idle doesn't happen with EFI cars for emissions reasons... the IAC is programmed to open upon return to idle such that it doesn't happen fast. A carburated car has no such limitation...

Now, you may be able to tune the PCM to give you what you want, I don't know.

 

Hmm...thanks for the info. I've never heard about that before. I am fairly new to the whole EFI/LS1 world. I usually play with carburated engines.

Hopefully someone will chime in with a possible solution.
Thanks again.

 

I've been reading a little and was wondering:

If you were to increase the speed at which the IAC operates, would it return to idle faster??

 

lose some stroke and some weight on the rotating assembly

 

14:1 compression makes a motor very rev happy. Something your TTs won't like.

 

Rev it in neutral with a 200 shot....oh ya and a u/d pulley

 

 

agree,

add to that a light weight connecting rods .

 

As for revving up fast, make more power

But for the coming down, I'm with the IAC stepper idea. Decrease the use of the IAC or increase its closing speed. Or...carb the LS1?

 

Agree and maybe you can find a liter converter.

 

Yeah, but have you guys checked on the prices of lightweight LS1 cranks, rods and pistons. That **** isnt cheap by any means. And he will likley end up with atleast 6k in the rotating assym by the time its ready to go into the block.