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Discussion Starter #1
Here's what I put down:

corrected for elevation

uncorrected


Here's stock vs. mods:

corrected for elevation

uncorrected


Mods: Helix d/p, JoeP MBC, Pace FCD, Perrin Pulley, K&N drop-in.

I definitely need a bigger turbo to make more hp, boost went from 21psi falling fast to 12psi at redline :roll: . As always, I had a good time :lol: .
 

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weeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee!
 

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The factory ECU cuts fuel above a certain boost pressure (I believe it was in the 17 to 18 psi area). The FCD removes this fuel cut and allows you to run higher boost. If you know what you're doing, it's a good tool. If you don't, you could do some expensive motor damage :)
 

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Ah. Seems like something I will wait to leave to XEDE or someone to decide for me. :) Since the full engine management solutions should monitor what the engine is doing, they should be able to raise boost when safe and drop it when not I guess.
 

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That torque curve really makes me wonder about launch RPMs. Everybody says to to launch at 6000 RPMs, but with your car, you could get the exact same horsepower and around 85 more lb/ft of torque by launching at 4000 RPMs. :D
Does the 2000 extra RPMs matter in other ways? :-?

BTW, I was just reading about an 1,100 horsepower twin-turbo Lingenfelter Corvette that has to be launched at 1,800 RPM just to get traction. 950 lb/ft of torque at idle! :eek: Zero to 60 in 1.97 seconds! :eek:


EDIT: 145 more lb/ft of troque at 4000 RPMs than 6000RPMs! :D:D
 

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any one want extra set of stock tires cheap

Talk about a car that's just begging for AWD..... or at least a mid-engine for some higher rear weight distribution. :)
 

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FS: Tamiya 2004 WRC STi radio controlled car.... 4WD

bitabur said:
Talk about a car that's just begging for AWD..... or at least a mid-engine for some higher rear weight distribution. :)
You mean the Lingenfelter 'Vette? I don't think there's room up front for the AWD diff. :-? 427 cubic inches for converting high-octane into lots of noise. :D
You can download the Acrobat file on that car here:
http://www.lingenfelter.com/images/CF427TT_eprint.pdf
 

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Discussion Starter #12
M said:
That torque curve really makes me wonder about launch RPMs. Everybody says to to launch at 6000 RPMs, but with your car, you could get the exact same horsepower and around 85 more lb/ft of torque by launching at 4000 RPMs. :D
Does the 2000 extra RPMs matter in other ways? :-?

EDIT: 145 more lb/ft of troque at 4000 RPMs than 6000RPMs! :D:D
Looks that way on the dyno BUT, the reason it has that much torque at 4k is because it's seeing 20psi of boost. No way I could build 20psi of boost off the line. I need to launch at about 5500-6000 rpm's to get a killer launch.
 

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Scuba_Steve said:
M said:
That torque curve really makes me wonder about launch RPMs. Everybody says to to launch at 6000 RPMs, but with your car, you could get the exact same horsepower and around 85 more lb/ft of torque by launching at 4000 RPMs. :D
Does the 2000 extra RPMs matter in other ways? :-?

EDIT: 145 more lb/ft of troque at 4000 RPMs than 6000RPMs! :D:D
Looks that way on the dyno BUT, the reason it has that much torque at 4k is because it's seeing 20psi of boost. No way I could build 20psi of boost off the line. I need to launch at about 5500-6000 rpm's to get a killer launch.
Scuba, you are absolutely right about launching at 6000 to build up boost quickly after launching. You never get the full 400ftlbs of torque in first gear anyway because you fly through that gear so quickly that the turbo never has time to produce full boost.

BUT, if you want to get 20 psi in 1st, (if you have the traction for it, and the money for the broken axles and diffs) you still can. The use of a two step rev limiter at the staging line will help. Set the rev limit to 4000 RPM, and go full throttle at the line. Instant 20 psi waiting for the green. That's what I call a hole shot.

Not responsible for transmission, axle, differential and engine damage from trying this launching technique. It works, but may cost you a lot in the long run.

Also, I truely believe that your STi makes a ton of torque compared to most V8s, but the torque curve of a V8 is what makes it exciting. 400ftlbs of torque is awesome on ANY car, but when a V8 has 400ftlbs at 1500 RPM, that is a pretty awesome sight also. I still rather have the turbo motor, due to it's efficiency, but I since I have experience racing both types, I still had to comment.
 

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Discussion Starter #14
jeffsti said:
BUT, if you want to get 20 psi in 1st, (if you have the traction for it, and the money for the broken axles and diffs) you still can. The use of a two step rev limiter at the staging line will help. Set the rev limit to 4000 RPM, and go full throttle at the line. Instant 20 psi waiting for the green. That's what I call a hole shot.
A two step still wouldn't build 20psi, 8psi maybe. Thanks though :D .
 

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Scuba_Steve said:
M said:
That torque curve really makes me wonder about launch RPMs. Everybody says to to launch at 6000 RPMs, but with your car, you could get the exact same horsepower and around 85 more lb/ft of torque by launching at 4000 RPMs. :D
Does the 2000 extra RPMs matter in other ways? :-?

EDIT: 145 more lb/ft of troque at 4000 RPMs than 6000RPMs! :D:D
Looks that way on the dyno BUT, the reason it has that much torque at 4k is because it's seeing 20psi of boost. No way I could build 20psi of boost off the line. I need to launch at about 5500-6000 rpm's to get a killer launch.
Ah, yes the boost. I'm more used to NA engines, I forgot the effect the time to build boost would have on a hard launch.
My newest reading is "MAXIMUM BOOST - Designing, Testing and Installing Turbocharger Systems"
I'll know better next time! :D


BTW: RIP John Lingenfelter, you're genius will be missed... :cry:
 

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RIP, john lingenfelter...
when did he pass. i had heard he was in a bad state the last few months but that he was stable. its worth mentioning that he hurt himself racing, i believe a Cavalier?, just another man all too aware that there are no borders or boundries in the performance world. too many great minds passing on before thier time.
 
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