Progress springs and sways question

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Progress springs and sways question

Postby Wingsandrotors » Wed Jul 20, 2016 4:18 pm

Hello to all, this is my first post on this forum and kind of new at this stuff. I have a 2008 Gt prht. I just installed new progress springs and sways and the difference is amazing. The sways are in the softest position(the end hole). I took it in today to get an alignment. The shop I used is competent and well respected in my area. The specs are Front camber -1.2 caster 6 toe in 1/32 per side, Rear camber -1.2 toe in 1/32 per side. The car has a significant amount of torque steer to the left. It has the factory LSD, is this normal due to the significant reduction in body roll? The car has always pushed pretty hard in the curves but straight, now it seems that push is more to the left. I'm very happy with the drop at 14" front and rear? Thanks Steve
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Re: Progress springs and sways question

Postby Brian » Thu Jul 21, 2016 7:22 am

Reduction in body roll has no connection to torque steer.

Likely alignment shop did not get numbers same left to right across the car.
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Re: Progress springs and sways question

Postby Wingsandrotors » Tue Jul 26, 2016 5:10 pm

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Well after much grief trying to solve this problem I called a friend of mine who did a lot of road racing when he was younger and he said "have you checked the circumference of your tires", I said " no they're brand new Michelins" he said, "doesn't matter" he'd seen tires with as much as an inch difference in circumference. I thought he was crazy but guess what! He was right! 1.4 centimeters difference, over half an inch. Only on 1 tire. I moved it to the left rear and Viola! It pulls hard right on Acceleration. I moved the mismatch to the front, car drives perfect. I've heard people say "it's probably your tires" but no one ever says why. My tire shop is ordering me a new tire. Problem solved :)
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Re: Progress springs and sways question

Postby Brian » Tue Jul 26, 2016 10:10 pm

Wow, that's a big difference....good catch.
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Re: Progress springs and sways question

Postby morrisg » Thu Jul 28, 2016 1:57 pm

I never woulda thunk it…1.4cm difference in diameter??? For gosh sakes, the tires are molded in a steel mold that is CNC machined for that tire size! My brain still doesn't understand how something like this could happen. Many thanks for posting this, at least now I know it can happen and will check for it if I experience tracking problems in the future.
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