View Full Version : 03 grt traction help

07-27-2010, 09:40 PM
Thanks for any help anyone can give. I am running a 2003 GRT with a 604 crate, the track I run on weekly is usually hooked up early on through hot laps and heat races, but by feature time the track goes extremely slick, this track is gumbo, car is very good getting in the corners and handles good through the middle but coming off the corners I have nothing, the rear tires just break loose every time I get in the gas, and I'm not just slamming the pedal down I am trying to use throttle control but I just can't get any forward bite. Any suggestions on what I could do to help would be greatly appreciated.
Car setup is:
550 lf 350 rf
200 lr 250 rr
running 125 lbs of wedge, j-bar 2 notches from top on frame, bottom hole on pinion,
left top bar is in 2nd hole from top , left bottom bar is in 2nd hole from bottom,
right top bar is in 2nd from top, right bottom is in 3rd from bottom
running limiter chain with about a half inch before rear end hits underslung
running d-21 tires.
will be glad to post any other info needed to get some help.

07-27-2010, 10:35 PM
These cars like about 185 lbs of bite

07-27-2010, 10:50 PM
That's one thing I will try changing this week, just don't really want that much wedge early on when its tacky.

07-28-2010, 05:40 AM
Whats your 5th coil spring and wheres your bar set at?

07-28-2010, 09:04 AM
325 lb spring in the 2nd hole from front

07-28-2010, 08:07 PM
You might try a 275 spring. How much travel you getting out of the shock?

07-28-2010, 08:11 PM
Almost forgot try lowering left upper bar down. It works for some if you have too much loose roll steer.

07-31-2010, 12:02 PM
Put lr lower bar at the top, raise the j- bar up on the chassie inch or two, about 300 lb 5th coil spring, this is for when it slicks off for the main.

08-02-2010, 02:50 PM
okay correct me if i'm wrong but won't raising to lower left rear bar increase loose roll steer and take away forward drive?

08-02-2010, 06:01 PM
If you just raise the lr bottom bar alone you're going to gain roll steer and loose spring indexing, the only thing that is a plus is you will be gaining drive angle through that bar. In my opinion though what your going to loose in indexing and gain in roll steer is going to out weigh the drive angle gained. If I were you and let's say you just adjusted the lr bottom bar I would lower it one hole on the chassis. You'll feel alot more drive because your going to loose roll steer and gain spring indexing, both of which are going to help in the slick.

08-02-2010, 06:40 PM
That is what I tried this past weekend, it helped with drive but when I put the left top bar in the top whole I couldn't drop the lower bar it was like in a bind from the traction shock I guess

08-03-2010, 08:05 AM
The last post is the first time I saw you talk about a traction shock. The first thing I would do is take that off. We tried on and off for close to half a season to get our 02 GRT to work with a traction shock, but it never felt better than when we took it off.
I would start there and then look for adjustments.
Hope this helps!

08-03-2010, 09:13 PM
I will try taking it off this weekend if it goes slick, with the shock off i should be able to raise to left top bar up and still lower the left bottom bar an extra hole to reduce some roll steer and add some drive

08-04-2010, 12:12 PM
if you have the small four bar holes you need to start out with all bars in the standard location except for the upper right bar needs to be one hole up. as the track dries lower both the right side bars one hole. then if you need additional traction raise the left upper bar. DO NOT raise the LEFT LOWER BAR! this takes away traction. i used to think that raising it would add traction but i spent a full day with my car at ray cook's shop and he set my car up. do not raise the left lower bar. leave it in the standard hole. if you want more traction and want to run around the bottom of the track you would actualy lower that bar. also sounds like you have way too much panhard angle. keep it in the 2nd notch on the pinion then call grt and ask how high to set it on the frame if you don't have the radiused frame mount. also, i would run 250lr spring and 225rr spring. try those things as well as taking off the traction shock. in place of the traction shock you need to run a limiter chain attached to the axle tube though.

hope this helps.

08-04-2010, 12:25 PM
One thing that should be taken into consideration is how tight the corners are.. If they are more tight than sweeping and the bottom is preferred than raising your Lrl one hole and lowering your rrl one hole can help you roll around the corner.. Try more wedge like another suggested and if it's too tight raise the lrl before ur next trip out, as the track slicks drop the rrl to tighten entry and if you need more drive either raise ur lru bar or move the lrl bar back down..