l8brakr

It's all about leverage. I bet you know this but for the sake of others I'll explain. The force applied at the hub will incrementally be higher due to the extra distance from the fulcrum point. For example a 100lb weight at the end of a 1ft bar will apply 100ft/lb of torque. Apply your 5mm spacer and it can now apply 101.64ft/lb of torque. This same principle applies to the leverage the tire patch location has on the spring rate. The percentage difference from your 5mm spacer could be calculated if you have the length of the A arm and at what distance the suspension pickup is located. However, the effect on spring rate could all be mooted depending on what pressures you run in your tires so...

glagola1

Wow. 245s....That's amazing. I guess it makes some sense since I found the hoosiers I ran, both the A4 and the A5, would push more than the 710's which are almost impossible to get understeer from.

Good luck in September.

pinkertonpunk

Matt, are you running in Sept? I didn't see your name on the list? Not that I registered yet or anything....

Damn engineers...

-Colin

glagola1

I wish. Maybe next year. That's just too much time to take off and I have only two days of vacation for the rest of the year! Damn honeymoon killed my vaction time.

Good luck to you too.

pinkertonpunk

Thanks.

I'm not crossing my fingers this year. I am now on the fence about 245 fronts as well from Steve's results. I am going to wait to see how they are wearing after this weekend I think though. Plus, if it rains again I am screwed, I can't afford rain tires.

-Colin

teamking

[QUOTE=l8brakr,Aug 22 2006, 01:31 PM]It's all about leverage.

Mad_Paradox

I am currently running 17x9 +63 all around on 255/40 and the only rub i get is from turning the steering wheel all the way to either side. I think if you get a high spring rate max camber you wouldn't rub at all or much. I rub sometimes on real bad bumps and things not on any turns yet

daverx7

I am strongly considering going 245's at all corners. What parts would I need to get for autocrossing and the drove home? (i.e. 5mm spacers for fronts, new lugs for the autoX wheels/tires?, new lugs nuts for the street tires)

Sorry for a potentially stupid question. :-)

Thanks,

-Dave