Where to begin on suspension?
#31
10-29-2009, 06:54 PM
Registered User
Actually I do change out for track use. I don't like running the street tires on the track, but do take them as "back-ups". I generally run the same size diameter within the 3% range. When I last ran MPSCs on the car I was running 235-40-18s up front and 295-30-18s on the rear. Swapping to these (running OEM Turbo Twists) was part of my "pre track" brake bleed and suspension check.
Putting it on the lift and getting it in the air before jumping in the car and hitting 170mph+ is something I strongly recommend for anyone planning to track the car...
As far as track tires for 2010, I'm not 100% sure which direction I'm going. I'll start on MPSCs but want to move off as I progress... Just don't know "which" tire I'll move to yet.
Mike
Putting it on the lift and getting it in the air before jumping in the car and hitting 170mph+ is something I strongly recommend for anyone planning to track the car...
As far as track tires for 2010, I'm not 100% sure which direction I'm going. I'll start on MPSCs but want to move off as I progress... Just don't know "which" tire I'll move to yet.
Mike
#32
10-29-2009, 07:00 PM
Registered User
Yup, Jon, Last year that alignment setup was a very good setup for me. I hope that the new trans, the motormount and transmount changes, along with the tranny cooler, and a few other improvements will help continue that trend next spring!
Mike
Mike
Jumping into the thread a little late...
The alignment setup that Mike Kelly described for his "next spring" adventures is exactly what I have been running this year. The car just rolls through the corners flat and firm. I got nine, yes nine, track days from a set of Michelin PSC's, and I would have gotten another two more if my boost hoses hadn't come loose and coil packs went south. The tire wear is even all the way acrossthe tread face. When I first got this car, I got 3, max 4, days out of a set of tires because of excessive shoulder wear. And I am a lot faster now, too.
Sway bars are the best first mod, then something to let you get sufficient negative camber. I have GT3 lower arms in front, and AP adjustable upper dog bones in the rear. This allows me to fairly easily go from street to track settings in my garage. If you do this, you really should invest in some alignment tools. I have the Smart Camber and Longacre toe kits. It really isn't that hard to do.
Jon
The alignment setup that Mike Kelly described for his "next spring" adventures is exactly what I have been running this year. The car just rolls through the corners flat and firm. I got nine, yes nine, track days from a set of Michelin PSC's, and I would have gotten another two more if my boost hoses hadn't come loose and coil packs went south. The tire wear is even all the way acrossthe tread face. When I first got this car, I got 3, max 4, days out of a set of tires because of excessive shoulder wear. And I am a lot faster now, too.
Sway bars are the best first mod, then something to let you get sufficient negative camber. I have GT3 lower arms in front, and AP adjustable upper dog bones in the rear. This allows me to fairly easily go from street to track settings in my garage. If you do this, you really should invest in some alignment tools. I have the Smart Camber and Longacre toe kits. It really isn't that hard to do.
Jon
#34
10-30-2009, 12:43 AM
Mike, thanks. Definitely getting them. I am sure you don't change wheels and tires much, but what do you think about changeouts, will it have an adverse effect on handling and setup if I go from say PS2's to another brand, with same wheel diameter, but different offset wheels and different overal diameter?
IMO the most important thing to get rid of if you are tracking the TT on a regular basis is the rubber bushings and bearing that wilt and wear on top of being many years old in our cars.
Additional caster is caused primarily by adding camber with lower control arms, if you just use good camber plates, you should be able to get more out of it. Plus more caster is a GOOD thing as long as you can control the toe and keep from rubbing.
#35
10-30-2009, 05:54 AM
More important that the wheel diameter is the ratio of width between front and rear. For example if you increase the front wheel width by 1.5 inches and the rear by .5, you will now have added more contact patch in front than rear, so you can dial out more understeer. So keep that in mind when buying wheels.
IMO the most important thing to get rid of if you are tracking the TT on a regular basis is the rubber bushings and bearing that wilt and wear on top of being many years old in our cars.
Additional caster is caused primarily by adding camber with lower control arms, if you just use good camber plates, you should be able to get more out of it. Plus more caster is a GOOD thing as long as you can control the toe and keep from rubbing.
IMO the most important thing to get rid of if you are tracking the TT on a regular basis is the rubber bushings and bearing that wilt and wear on top of being many years old in our cars.
Additional caster is caused primarily by adding camber with lower control arms, if you just use good camber plates, you should be able to get more out of it. Plus more caster is a GOOD thing as long as you can control the toe and keep from rubbing.
So having more contact patch in front decreases understeer correct? Funny you mention this. I had wider wheels and P235's in front when I had it aligned and went back to my hollows with 225's and my car understeers more now and I don't like it. I asn't sure why I had more understeer, but this makes sense
#36
10-30-2009, 06:58 AM
Going this route can change caster and interference in the front of the fenderwell. We had to move the radiators forward about an inch (plenty of room to do that).
Jon
#38
10-30-2009, 02:15 PM
Registered User
The JICs have a different design that really does allow them to go further inboard. It's probably the biggest advantage of them, but not accessable once they are set and the car is on the ground, unlike say a Ground Control or Global West style camber plate that's adjustable on car!
Mike
Mike
My experience is that camber plates don't help on this car. I went this route, and we ran into an interference where the strut hits the side of the fenderwell before getting to even -2 degrees. Lower control arms are the way to go. 14mm shims takes me from street setting (I forget - about -1.2 deg?) to track setting -2.5 deg. This also requires almost 10 turns on each side to correct toe.
Going this route can change caster and interference in the front of the fenderwell. We had to move the radiators forward about an inch (plenty of room to do that).
Jon
Going this route can change caster and interference in the front of the fenderwell. We had to move the radiators forward about an inch (plenty of room to do that).
Jon
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