Friday nights Dupage area

[Thirdgen89GTA]

yeah bills a smart dude, I would never sit in my house and try to figure this out. I think my head would explode.

Still bill I don't think my st... is all that light, it might be about a half a pound lighter then your truck but think off all the aluminum you've got on that thing. If your truck had as much plastic as mine it would be just as light.

One more thing on the 30's I drove bills jammin w/ O.S. 30 and that thing was sick at leisure. There wasn't a single place your could smash the throttle, and if you did in the straight you'd be in the wall at the end if you blinked. But other then that the engine was so unusable because the bottom end on that thing was sickning. You could come out of a turn and goose it right into a donut. I don't know why anyone would want to use that to race unless it was in a monster truck or heavy truggy.

Yep, and the 528xr was even worse. I remember the last time I tried to drag race it. Lined up all nice in the "left lane", got anxious off the line and gave it too much throttle. I ended up crossing in front of Slaytanic doing a u-turn unintentionally. It was sick.

But in reality, the 30vg isn't uncontrollable, though it is very punchy. The powerband isn't smooth like a nice .21, it makes its power like a muscle car. Sheer, brute force. Though it does rev quite well, on par, or slightly better than a Novarossi 528xs (not XR, whole different ball game there).

In order to figure out engine RPM from trap speed you need to know the following.

Primary ratio ( clutchbell / spur gear)
Secondary ratio (pinion / ring gear)

centerdifferental DeltaV (differential rpm between front and rear output on the center diff, highly dependent on the weight of the fluid used. I had to research a formula and contact my college physics professor to figure this out)

Overal tire diameter, as well as tire expansion under high G-force. Each tire is different so I had to measure it statically and under load. This ties in with the center diff differential rates. A locked center diff would eliminate this variable

Roll Out - Rollout is calculated from the overall tire diameter and is basically the circumfirence of the tire. A 5" tire diameter has a 15.7" rollout. Or that means it travels 15.7" per revolution.

From there its a nice formula that I do NOT have the time to type out here on the forum. But if anyone wants it I can send them the excel spread sheet and they can figure out their own ratios.

I don't gaurentee 100% accuracy, but I do know that it is fairly accurate. The only true way to check is to get a sensor on the flywheel and measure crankshaft rpm as compared to wheel rpm and trap speed.