Body roll

[flattop]

I think i have to much roll. ride heights 71/4lf, 73/4rf,91/4lr,93/4rr. springs 1200lf,1450rf,100lr,200rr.left side 53% rear 50% bite 88lbs. high banktrack 25 to 30%. car bottoms out the right front a arm and the right rear axle tube likes 2 inches of hitting the chassis. car is fast for first part of race than gets loose in the middle of turn. the right rear gains 4psi the left rear 0. rr is 25 degrees hotter.any ideas?

[dirt2]

check your private messages.

dirt2

[flattop]

It says i dont have one. oh this is a metric chassis. With a 7 inch shock on the lr it pulls the tire off the ground.

[ToddSmith16]

Ride heights in rear are to tall. Shouldn't have more than a 1 inch difference between LF and RR. Need to put a 9 inch shock on the rear. Your rear % should be around 53%. Try springs of LF:1000 RF: 1100 LR: 275 and a RR of 225. Have your bite around 160-200. You will see a world of difference!

[flattop]

No time to switch everything. tried 9 inch shock and put 4 rounds in and out on weight jacks. car is the same bad fast for 8 laps than goes loose in middle. an burns the rr off. lr 109degrees rr135, rf 105,lf nothing. car bottoms out the right side. put it on scales 212bite. rf raised 3/8,lf down 1/2,lrdown 3/8,rr up 1/2, 4 rounds out of rr and it raised 1/2 inch is that right, 4rounds in lr it went down. had 13inch 200lb spring in lr but spring could fall out so put 20inch 100lbs in it. car was the same with the 200lb spring. only raced 2 times last year.

[DANNY]

Is this on a dry track or heavy or any?

[flattop]

track is hard ,dry not to dusty. track is the same every week. hot laps little dusty, put 2rounds in and out for heat had to feather the throtle middle off. put 2 more in for featcher, car truns in on it own and back on the gas for 8 laps than loose

[ToTheFront]

There's several things I would change but the one thing that jumps out at me is the left side weight.

If there truly is that much banking, you could go up on your left side weight to something like 55-56% and put your weight low if it isn't already.

[DaveBauerSS6]

What kind of upper a arms and ball joints are you running?
I think you have a typo on the front springs. If not, you have a dead RF/ RR shock or a bad roll center number. What shocks are on it? 1450 lb spring is too heavy.

[ToTheFront]

What kind of upper a arms and ball joints are you running?
I think you have a typo on the front springs. If not, you have a dead RF/ RR shock or a bad roll center number. What shocks are on it? 1450 lb spring is too heavy.

I agree, something is definately out of whack here. On a real high banked track you shouldn't experience much roll at all, should be dive mostly.

Do you have all of your weight mounted really high?

You're also too soft at the RR for that type of track in my opinion.

[flattop]

after market a arms tall ball joint lf short rf. lf 74 rf 75 93 rear. kept going up on rf to stop it from hitting. still hits.

[flattop]

the other cars u see the roof mine u look at the side. so something out of whack. weight is mounted on chassis to ten inches high.

[DaveBauerSS6]

after market a arms tall ball joint lf short rf. lf 74 rf 75 93 rear. kept going up on rf to stop it from hitting. still hits.

How close are the a arms mounted to the frame?

[ToTheFront]

Stiffening rf spring just makes it worse, you needed to soften it so it wouldnt bottom out.

Wt transfers to the stiffer spring up front first and more... if your lf was stiffer than your rf it would do something as it is now its doing nothing.

This is exactly right, this is one of the most misunderstood concepts of chassis setup.

When you soften the RF spring, it forces the LF to support more weight, which results in more grip across the front of the car.

[flattop]

Thanks for the info i am going to put ls weight. checking frontend settings. i think i got the upper on the right its a 91/2 spaced about 1 inch inside the mount. if i put a shorter arm would it move the roll point over an not roll as bad? thanks again.

[ToTheFront]

Not sure about the RF arm, my best advice would be to leave it alone if your frontend settings are good.

I'd go up on the LS weight, set the front ride heights level, set the rears about 1/2 to 3/4" higher than the front. Put the 200 back in the LR, try about 55left 52-53rear 50-51cross.

Shouldn't be any reason that won't work for you, as it is, you're working the RR to death.

[flattop]

just got the front level tonight start on ls tomorrow. thanks guys.

[ToTheFront]

flattop, disregard anything I suggested, ask Jeff J for help, he knows the only way to make it work.

[flattop]

Going to switch rf a arm. did not have any camber gain. 9 inch spaced 1 inch inside mount to 71/4 outside.mount.

[DaveBauerSS6]

Thanks for the info i am going to put ls weight. checking frontend settings. i think i got the upper on the right its a 91/2 spaced about 1 inch inside the mount. if i put a shorter arm would it move the roll point over an not roll as bad? thanks again.

What my question was about the upper arms was to ID if the inner mounts were above the frame by say more than 1 inch. To get a ballpark roll center on the metric frame you need the arms mounted close to the frame and tall upper ball joints as the rules allow. Roll center affects spring rating as well as other other things.
Shortening the arm length will add more angle in the direction you want, but will affect you roll steer, bump steer. I would'nt change that to correct your concern. You are in the ball park now.

You have done some work, but have not mentioned your shocks.

Check the shocks and tune with them, one or two number change will take out a bottoming. Drop the springs down 900 lf and 1000rf, you will increase you forward bite when you get weight transfer from the lighter springs. I cant imagine how you can drive a rough track if needed. A 1450 spring would beat your eye balls out of your head on our tracks. LOL. I tried a 16 and 20 inch LR springs and saw no advantage. I run 13 inch and my car has plenty of LR bite.

[flattop]

Went to 7" a arm to get 1 degree camber gain. my a arm is about 1/4 off the frame on the front an level to the back. 74lf 75rf 93rear.

[flattop]

To the front an the win!

[ToTheFront]

Congratulations!