For those who are interested..

I ran a new best in my car last night (383 Crossfire Vette)

12.53 at 110.2

previous best was 12.81 at 106.7..

the gains came from a cam swap to a comp 12-430-8 . (280/280, 224/224, 0.560/0.560, 110LSA)

Not too shabby for TBI huh? ;-)

Ben.

 

Man that's a killer time! Great job! What kind of crossfire setup are you using? Ported stock; x-ram?

 

2" TB's on an X-Ram. 90lb'ers at 20psi.

 

That's very encouraging, how much does your Vette weigh out of curiousity? IIRC you swapped to a newer PCM like a 7060 or something correct?

 

I believe it weighs 3400lb with me (200) in the seat.
Yeah, now running a '8625 PCM.

 

Those are great times. In all reality that cam is still pretty small for a 383. the 110mph traps are very good, I image you had some traction issues out of the hole, with a dead hook, that MPH should be good for more.

 

Your running a 4 bbl as well, correct? Very good times.

 

Awsome times, what were you able to get your PW down to? I'm intrested to see because I'm pretty sure your the fastest documented TBI setup on the boards. Your the guy figuring out how far we can go!

 

i think Ben took off the holley 4 bl tbi and came back to xram with two single barrell(stock CF) TB's bored to 2.00. just goes to show tbi is ok with air flow. issue is fuel flow. i suspect he is not static with 90's at 20 lbs or dam close to it. i bet he is spinning at 5300-5500 rpms with that cam??? Ben what ratio are rear gears?

 

Ben: what tires?

 

I did play with a 4bbl TBI for a while, but it's long gone.
Currently running 2" crossfire throttle bodies, and dropping about 6kPa across them at WOT.

90lb injectors at 20psi are peaking at 89-90%, finally got that under control ;-)

Tyres are ordinary Falken street tyres, 255's.
Rear end is 3.07, shifting at ~5500


And Dewey, yeah i am already wishing i went for a bigger cam, this one was too easy to tune ;-)

 

dropping 6 kpa? that means you need more air? find a spare set and time to sleeve?

 

Eh, thats not too bad. Like 2 inHg of vacuum. Definatly could be worse.

 

I said the same thing after I got mine running.

 

Great progress with your car Ben.

Why did you dump the 4bbl Holley? I know about the injectors but I thought that you said that you had them under control. That thing should have flowed enough air.

Even for your next cam

 

I had the holley 4bbl working well, but I just wanted the challenge of doing it with 2 bbl ( or 2 singles in this case, same thing)...

Just to prove a point really, and maintain bragging rights
If i ran the same times with a 4bbl, you would say 'big deal'...

 

Excellent times.

You've got a ways to go with the fuel pressure if needed.

Hindsight is 20/20; wished I had gone with a bigger cam and more compression. I'm working on the cure

 

Congrats on the time Ben!

Hmm, I'd like to see what you'd be running with a larger cam.... along with some 3.73's.