What is needed to build a 7 second (1/8th) street car

swinger340 said

Car has 3/8 pick up tube and fuel line w a Holley high volume mechanical fuel pump. I dont want to use the NOS. It is a 10.2:1 motor. Did dyno 448 5 years ago, carb has been played with and changed multiple time since. has 75Lbs oil pressure and no smoking, runs 175 degrees. Fun car do drive on the street, but not meeting its full potential. ill keep tweeking fuel timing and traction. Taking sway bar off, installing slant 6 tortion bars a good place to start?? The barry grant 850 and 2 " carb spacer that it was dynoed with are long gone. May be a good 20 HP loss there.

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Needs better tires. I'd get some 28x11.5x15 ET Street Mickys, should fit just like 275/60/15. You need to get the 60' times down around low 1.6 to high 1.5. Next I'd ditch the Dominator intake for an Eddy Performer RPM or Air Gap. That motor needs torque and the RPM will give it that with no loss of top end HP. I've swapped quite a few M1 and Dominator single plane intakes for RPM and AirGap intakes on the dyno and at the track. They worked better each and every time, sometimes as much as 3 tenths and 2 MPH in the 1/8 alone. Results vary though. You didn't mention your exhast system, but anything less than 3" will hold you back. When I went from 2.5" to 3" I shaved around 2 tenths/gained 2 MPH in the 1/8, on a 375-400ish HP motor.
Would lower gears help ? Yes. Would more stall help ? Yes. What would the gains be ? Minimal, you're pretty close with what you got. Would the gains be worth the $ at this point ? No Would a higher delivery fuel system help ? Maybe (if it isn't fartin, poppin, or breaking up you're more than likely fine) but as Cracked said it can cause a lot of grief. Suspension mods will help, but street tires will only hold so much power, especially if you start putting down more power at the line. It always comes back to a good 60' time. Good luck !