YZ-2 Straight line stability

[Sean T]

I've run the YZ-2 for two meetings now, but cant find why im have problems with straight line stability. under heavy braking at the end of the straight the car pulls to the left every time, then as soon as i come of the brakes it will straighten up. then under hard acceleration at the start of the straight it pulls to the right. if i feed the power or brakes in very gently then there's no problem.
Im running kit setup apart from shock oils and springs, weight under lipo & 20g in front of servo, all of the transmission is free running with the gear diff with 3K oil, all the suspension is free moving. I thought it was steering setup at first but now the cars been on a setup system its all fine running 0 deg toe. it was then setup with 1 deg toe in, but this has made no difference to the handling.
Im running on smooth astro indoors with Schumacher Blocks Rear/ Cut staggers Front.
Any ideas before i strip it down.

Sean.

[shark]

Double check the shocks are of equal length .
Also Spring collets are equal .

[Sean T]

I've gone through the shocks & spring all are equal, droop settings all checked. arms are all equal on setup board. Shocks have been swapped from left to right.

Sean.

[discostu]

Where are you racing it sean

[discostu]

It's gonna be some thing silly like a anti squat insert inserted wrong left to right maybe a caster insert up side down left to right pissibly a binding drive shaft seased bearing

[Sean T]

I've been running at FORCC.

Everything is free running. so was looking at the diff to be causing the problem. just going to start going through it now. just thought i would ask before i start stripping it down.

Sean.