sactown

No bog at all, just bring the rpm's up to 4500 punch it and side step the clutch. Those bias ply's hook up and you go. got a vid somewhere is the front tire coming off the ground going into second, hope to have one of the front tire lifting during launch tomorrow.

stealth_GT

Noice.. I am gonna try both methods of launching.. off idle and @2800 rpm (auto/4.10s)

Trying to get it down to 1.5 60 ft.

Riptide

What about dumping the clutch with a drag radial vs. a bias ply? Still a good idea?

stealth_GT

Bump..

so do I have to set the tuner up for these new wheels and what's the tires/revs needed??

Simon1

The only time I ever bog is when I don't go WOT fast enough. Usually that happens when something is different durring staging and I get distracted.

I now launch off of the 2 step, but not WOT with the clutch side step cause I will blow through the tires. I just hit the limiter and go a little passed it.

You guys with a little less power and a clutch that is not an RSt have to remember the RST is also very forgiving off the line. It does slips just right when we side step the clutch. Sometimes I will ride the clutch a little bit, but not much. Very rare.

And Sactown is launching on a set of 15x10 Bogarts. He has more traction possability than anyone on this thread. Even though I have 60' better than he has. I hope that changes.

1.5 for sure if your track is in decent shape.

Depends on the track and your suspension. I try to get my rear suspension adjusted to where I can side step the slutch. Sometimes I can't. Side stepping is usually easier.

Don't worry about it. Your racing, not driving around twon worried about getting a ticket cause you were 5 over the limit. Those tires are probably close enough to your other tire that it won't make a difference.

Dang it I wish I was racing tonight.

stealth_GT

Thanks for the tips again

For some reason I thought that if I didn't tune for the tires, the shifting would be off...

Can't wait to head out there to the track!

Norm Peterson

Most tires turn about 20,900 / [tire OD] revs per mile, so a 26.0" tall tire should be turning about 805 revs/mile (to the nearest 5). Bias-ply slicks could be slightly different (I'm guessing a few more revs/mile than that). If it doesn't take very long to reflash the tire factor, you could change the factor between runs to see if it makes much or any difference.

FWIW, all of the online revs/mile calculators I've ever seen use 20,168/[tire OD], which does not account for the effects of tire tread distortions.


Norm

Riptide

You guys dumping the clutch with 400+ whp and track tires.

Done it with the stock clutch? Did it hold or did you fry the thing? Mine holds fine from a roll however I wonder if the story will change if I'm reving up high and dumping it.

stealth_GT

I might end up doing just that.. I remember when my speedo was wrong due to the 4.10s and the tune being set up incorrectly. I was 20-30mph over the speed I was actually going! Not until I was pulled over for going too slow did I realize something was wrong. Speedo was off, but I didn't realize just how off it was. Not only that, but it would reduce top speed and final gear more so than if it was correctly tuned for...

Simon1

It will hold the power for a little while. Mine lasted about 6 months after I had FI put on.