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redracersmod
06-28-2014, 04:15 PM
please critique my scale numbers I have an old dirt works chassis the last race was pretty decent but I think there is more that can be found. I just put the car on the scales this morning. lf 494, rf501, lr695, rr609 cross is 52% Left is 51.7% Rear is 56.7 If I add my lr gas shock I gain 20lbs lr bite and and I run it with the gas shock on the lr only all the rest is qa1 50 series lr 8/2, rr 4.5, rf 3/5, lf 5/3 tire stagger 3/4 in the front and 1 inch in back. ride heights are lf 5 3/4, rf 6, lr 7, rr 6 1/4 racing dry slick 95% of the time What do you guys think Thanks in advance

Lizardracing
06-29-2014, 07:52 PM
Looks pretty close if running "on the hook".
You might try around 53-54% left side.

What's the car doing or not doing?

redracersmod
06-29-2014, 10:12 PM
What do you mean by on the hook? The car handled fairly decent not getting over on the right front ive been having and a little more drive off would be nice But we always are wanting more off.

Lizardracing
06-29-2014, 10:56 PM
Slang term for four bar car, floated LR spring behind and shock in front left over from 20 years ago when the style of suspension just became mainstream.

Do you want the car tighter or looser and are you on the throttle at the point where you want it tighter or looser?

redracersmod
06-29-2014, 11:16 PM
This is a 2 link springs on top of housing. And would like it a tighter off on throttle.

Lizardracing
06-30-2014, 10:01 PM
2 link spring on top. That's a little bit different. Do you want to tighten exit or more forward grip? They are not the same.

The secret to a good exit is momentum through the middle. The better your entry and middle the better your exit will be.
To tighten the middle for a better exit I would first try driving the car straighter. Keep the rear end under you more. Them I would try adding PH bar angle. If that doesn't help much return to above specs and add LS weight to 54%. If it improves, stiffen the LF spring and go back to the 52 LS. If it's better yet to back to 54% LS. if entry is getting too loose to manage than stiffen RR spring. A spring rubber would be a good tuning tool here. Once your really close to well balanced than add RR bar angle to suit differing track conditions. On a two link you'll have to be really smooth on the throttle and try to choose a line than makes the corner as long as possible to give the tires time to grip.

UltimateRaceCars
07-01-2014, 06:44 AM
Your setup you posted looks pretty good, what springs are you using? Your trailing arm angles play a big factor in how much drive you have off the corner. In general I would say take bar angle out of the right rear as this will reduce loose roll steer and take drive off the right rear. Also you can increase bar angle to the left rear but becomes ineffective after it gets too steep.

redracersmod
07-01-2014, 12:29 PM
Spring rates are lf 500 rf 550 lr 200 RR 175I would like to have more forward grip

Lizardracing
07-02-2014, 12:16 PM
If the car is balanced well then about all you can do is increase rear percent. Figure out a way to make the middle work better for momentum.

Fox_hunter42
07-02-2014, 04:36 PM
put the lr spring in front, shock behind.