quote:

Originally posted by Footloose:
I forgot to tell you. It has 3.42's running 1st and 2nd. With the 4.56's I have to use 3rd. gear-shift about 6500

Alright, that's effectively 5.19 final gear. so 5.19 x 97mph x336 = 169152 / 29tire = 5832/6700 = .87057-1. = 0.129422% slip... 13% slip

Thats not bad.

quote:

Originally posted by Footloose:
Thats not bad.

I got a 6100 6200 PTC sprag converter slips 13% 114 mph, it's my least efficient converter crosses 7750....

The most efficient converter I have TSI spragless crosses 7400 114mph.

They both produce about the same et, TSI is hair faster.

But if the best parts of the splits on the slips could be built into one converter, you could pick up a half a tenth. That's a lot.

What you have is what ya need, you don't want one that tugs the engine down from accelerating rpm.

A good slip percentage is relative a fast time slip.

This message has been edited. Last edited by: Mike Rietow, March 13, 2022 09:35 AM

How is everyone figuring in tire growth when calculating slippage?

quote:

Originally posted by 27Keith:
How is everyone figuring in tire growth when calculating slippage?

DIVIDE DRIVE SHAFT RPM BY ENGINE RPM. That is the only accurate way of doing it. A data logger usually tells you the slip between the 2.

quote:

Originally posted by 27Keith:
How is everyone figuring in tire growth when calculating slippage?

I use my data logger, but 5% growth is pretty much perfect for my car.

quote:

Originally posted by 27Keith:
How is everyone figuring in tire growth when calculating slippage?

If it's a new combo without a single run, you use experience - hp vs. weight vs. final gear.

The tire manufacturer can tell you how much their tire will grow, according to mph.

quote:

Originally posted by 27Keith:
How is everyone figuring in tire growth when calculating slippage?

Easiest way is a data logger but with your speed and weight the tire manufacturer can give you the loaded radius. If you know someone with a similar tire size as yours who has a data logger, that will get you close too.