Drag Racing Tech - Nitrous gearing, what neeeds to happen here?

copied from yellowbullet

Nitrous gearing, what neeeds to happen here?

Combo is a 355" LT1, Ported 21 degree trickflow heads, stock ported intake, 13.4:1 Compression, E85, T56 6 Speed Manual Trans 4.30 rear gear
232 238 .629 112 LSA Hydraulic Cam
28x10.50 Hoosier Stiffwall
4.30 rear gear

Took it out for some shakedown passes yesterday, and it will hit the tires super hard, pull the wheels, then set down and bog.

It was cutting 1.89 60' times like this N/A.

I started spraying it on a 150 shot (.062 jet through an EFI Plate) and it started to 60 better, but I would run out of gear before the 1000' mark...

It went 1.56 1.53 on the .062 jet, then 1.49 on the .071 jet

The cam loves to pull at 6700+ but I dont know how far I can take it with the valve train thats in there...

Should I regear for the nitrous, swap to solid valve train and spin it up? What gear should I go with if I regear? I eventually want this car to run 9.90's

Should I get suspension before I do any gear swaps or spin it any higher? I plan on full AFCO Suspension from MADMAN.

Heres a video of an N/A launch at 6200 on the 2 step.
http://www.youtube.com/watch?v=jcQc4rK1xiI

Here's a video of an N/A launch at 4800 on the 2 step.
http://www.youtube.com/watch?v=2uKnZlFVG50

It is virtually the same 60ft time for both runs. Upping the 2 step and hitting the tires harder had no effect on 60, just a lot more violent in the first 10ft...

Here is a launch on the 150 jets, 1.53 60ft
http://www.youtube.com/watch?v=hDFYjNO-_Tw


Any help is appreciated.

I'm seeing the traction, maybe try launching higher or increase the tire pressure to allow a bit more tire rotation to keep RPMs up. Are you running a stock weight or lightweight flywheel?

Spray more nitrous off the line and put a 3.90 gear in it. You could use the morel link bar type lifters if you didn't want to go solid, but solid would make more power, spin higher, and be more reliable at those rpm's. I'd say with your CR you could take advantage of a bigger solid roller camshaft spec'd out for a heavier dose of nitrous.

What tire pressure were you running? On the nitrous pass it looked like it wadded the tire up pretty good. You got separation in the rear suspension now which is good, and the front end looked like it popped up well transferring weight nicely. Like the guy above me said about the tire pressure try adding some more air to get more wheel speed.

14 psi, it already has Morel link bars. I am having cam sensor issues though, maybe that's what is limiting me RPM wise.

Too much tire, not enough motor. Try slipping the clutch a tiny bit. I run the same tire you do with a 4.11 gear. You may want to look into a seperate set of tires for n/a runs. I run a 26" tire n/a and a 28" on nitrous.

14 psi, it already has Morel link bars. I am having cam sensor issues though, maybe that's what is limiting me RPM wise.

14psi is not what I was expecting to hear you say, I was figuring less.

Adjustable shocks? Does it have them?

FWIW I spin my heap to 7000-7200 but the springs I have were set-up for high rpm use.

Too much tire, not enough motor. Try slipping the clutch a tiny bit. I run the same tire you do with a 4.11 gear. You may want to look into a seperate set of tires for n/a runs. I run a 26" tire n/a and a 28" on nitrous.

This^^^^^^^^ Its exactly what happened to my car NA on a 28" tire. 355 just doesnt have enough TQ with that clutch and tire to keep it from bogging. Youll need a smaller tire for NA passes.

Stock suspension, but full AFCO setup coming soon. I probably will move to a smaller tire N/A.

Although I'm not going to worry too much about N/A runs because I want to maximize it on spray. Or boost if I go that route this winter.