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bcarter
03-23-2002, 09:50 PM
I'm running in a Spec class called Challenge Cars here in Calgary. 2 1/2 mile road course. Street-ported 12A first Gen. with 350 lb springs on coilovers with adjustable Tokicos on the front 205/60/13 RA-1 Toyos. Slotted towers, so I have about 2 1/2 degrees neg. camber.I am wondering about how much caster is good, and how about toe-out. I figure a little bit of toe-out for turns, and considerable caster for the straight (quite long and fast at the end). Last season was my first, did quite well, but now I am into tuning the suspension.

Any thoughts??

Festus E. Simkins
03-25-2002, 11:39 AM
I am now running 5 degrees postive caster, 0 toe, and 2.5 degrees neg camber. Car seems to rotate and turn in well. I decided to go to 0 toe because of the amount of caster I'm running. Also, I am tring to get as much straight away speed as possible.

My .02 http://Forums.ImprovedTouring.com/it/smile.gif

Drive well.

CrunchyFrog
03-25-2002, 07:46 PM
I would suggest max for both - whatever you can get from the stock peices...

3 degrees negative camber and whatever cater are ok...

0 to 1/4 toe out are also good to start with.

Remember negative camber takes away from braking efficency.

K

BrianB
03-25-2002, 10:29 PM
Get ahold of a pyrometer and take some tire temps immediately after a practice ,see what the temps tell you about Camber and tire pressures.
0 toe(or slight toe in) ,For high speed straight line stability and depending on the type and condition of your suspension bushings ,youre front end is probably going to toe out some under braking and turning in.Alot of toe in or out will slow you down on those long straights!
Brian

bcarter
03-26-2002, 12:19 AM
So far, so good...some good thoughts on this topic.

Bushings on the front all urethane, new last season, solid. Obviously, the neg camber of 2.5 isn't enough to take best advantage of the Toyos, we all get crumby tire wear, and after a weekend or so, we have to move them to the other side to balance out the wear.

Just rebuilt the steering box, and off to the alignment shop this week. I start the fronts at about 32 lbs and the rears at about 28 lbs, still trying to figure that out as well. Problem is, here in the Great White North, we don't get much time, if any, to practice, as today we still have snow and below zero temps. First time on the track will be a 15 min. practice, then Qualify...

Thanks guys, any more thoughts...?

Boy Racer

Allen Brown
03-27-2002, 07:22 PM
Brooke...I'm getting pretty even wear by running 3.25 passenger side and 2.75 on driver side. Toe out runs at 1/8". But I still have to watch the tires on the two mini enduros.

See you in a few weeks.