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Old 04-02-2013
JimboJames1972 JimboJames1972 is offline
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Join Date: Jun 2011
Location: Bury St Edmunds, Suffolk
Posts: 69
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LordNikon,

A few suggestions for your setup.

First off, tires on any GT12 seem to be about 90% of the handling. However, it is not just the compound you need to worry about but also the diameter and what additive (if any) you are running. After you have sorted the tires, play with damper gloop, ride height and weight distribution (in that order) and then play with springs, castor and camber.

Tires. Usual rule of soft tires giving more grip and harder tires giving less applies. However, softer tires also give a more relaxed, gentle steering effect (because the side walls can flex more) while harder tires give a more aggressive, pointy feel. Tall sidewalls also give more grip since the tire can deform more, but are more prone to chunking. General setup for tires is Pink Medium or Contact 32/35 rears matched to JAP Medium/JAP44 or Contact 42/45 fronts. Obviously, suitable tires vary from club to club but a 10' shore difference front to rear is about right. Going too hard on the front (to stop oversteering or grip roll for example) can actually make things worse becasue the stiffer sidewalls make the car too aggressive - weight is transfered more violently and you either oversteer or roll. When you true your tires, make sure the outer edges are VERY WELL rounded off, this will help stop the side wall from digging in and grip rolling/peeling off.

Damper. 30,000 oil is about right for most clubs, few I know of use anything lighter. Be aware though that 30,000cst and 30,000wt will NOT be the same! With the bottle I use (30,000cst I think - the label came off!) it takes a good 30sec for the air bubble to reach the other end if I turn it upside down. Refill your tube every three runs. If you are lifting an inside front wheel (too much pitching at the rear, not the front) this is the BEST way to cure it, leave tires and springs alone!

Ride height. 3.0mm is your minimum. Most drivers find that much over 4.0mm is too high. Run yours between 3.2 and 3.5mm and see how this goes.

Additive. If you are allowed to run additive try adding a wider width to the fronts but leave it for a shorter time. Eg, very, very light wipe of 2/3 width, leave for 2 mins, wipe off and race imediately.

If you are grip rolling, the first thing to check is that your tires are not coming off the rim, have not chunked and that the side walls are well rounded. If that is all ok, try SOFTER tires and SOFTER springs on the front (bear with me on this...) and set your handset to a lower steering throw (lower EPA adjustment). Run your fronts at a smaller diameter (45mm or less) and the thinner sidewall will offer less flex so steering will be calmer. However, softer compounds will still give you the turning raduis/arc you need. In mega-high grip conditions I run Pink Medium on the front as well as the back (!) but I half my truning radius on my handset. If you are still suffering, try the optional thicker wishbone plate or an additional wishbome brace.

My basic setup is:
Front - JAP 44 tires (45mm diameter, 2/3 additive for 1 min), kit soft springs, 1mm castor, 3.5mm ride height.
Rear - Pink Medium tires (47-49mm diameter, full additive), kit soft springs, no washers under the ball, 3.5mm ride height, 30,000 oil.

Hope this helps,

James
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