Unfriendly Race Car

[RacerX10]

I've got a fairly vanilla 4 bar car.

550 LF, 450 RF
225 LR, 225 RR

Pull bar with NO 90/10 damper.

52.5% left, 53.5% rear, 51.5% cross, ~ 80 lbs bite, no driver

Car is working fine , doing all the things I want it to do, except ..

When I've got to get out the throttle and it's up on the bars, the thing unloads and turns HARD RIGHT, which is horribly uncomfortable.

Are all the current "up on the bar" setups doing this kind of thing ? Does the driver just needs to learn to deal with it or can I do something to make it just go straight when I've got to dump the throttle in the middle of a corner (wreck ahead, not going to make the turn, whatever) ?

Thanks for any ideas. I'm just wondering if everybody's car is like this or I can do something about it.

[JCSullivan00]

We don't have a late model, but we have a spring behind mod, pull bar with no 90/10 and it does the exact same thing your car is doing. I'm anxious to hear some feedback. In the mean time, the driver is freshening up on his trail braking technique.

[GRT85c]

This sounds like you have a straight 3 valve shock for the 5th coil. Get a rebound adjustable with a 3 compression or a split valve of 3 comp. and a 6 or 7 rebound. This should make a huge improvement.
Hope this helps!
Tim

[RacerX10]

We don't have a late model, but we have a spring behind mod, pull bar with no 90/10 and it does the exact same thing your car is doing. I'm anxious to hear some feedback. In the mean time, the driver is freshening up on his trail braking technique.

I bet we both need to put a 90/10 on there.

[RacerX10]

This sounds like you have a straight 3 valve shock for the 5th coil. Get a rebound adjustable with a 3 compression or a split valve of 3 comp. and a 6 or 7 rebound. This should make a huge improvement.
Hope this helps!
Tim

Thanks for your comments. Don't have a 5th coil in this pull bar car but the idea is the same, I think it needs some rebound damping and hasn't got any at all right now.

[9WRACER]

What shock is on the lr? Had the same problem on my rayburn, if you had to dump the throttle quick car would try to turn right. Put a 7-2 shock on the left rear behind and problem went away. No shock in front on lr.

[RacerX10]

What shock is on the lr? Had the same problem on my rayburn, if you had to dump the throttle quick car would try to turn right. Put a 7-2 shock on the left rear behind and problem went away. No shock in front on lr.

I have a 4/4 shock on the LR (behind), and a 90/10 shock on the LR (front). Adding that 90/10 on the front did help, but I think I'd do better moving it to the damper position on top of the rear end.

I'm assuming your Rayburn also had a 90/10 on top of the rear end when you did the 7/2 on the LR ?

[TALON75]

sounds like you need more compression in the LR shock . If you like how the car handles other wise try just getting more comp. in the LR, the 90/10 won't have the same effect on it like the LR shock will .

[MasterSbilt_Racer]

More compression on the lr or a damper on the axle will help this problem. But this symptom is why pullbars are not common on 4 link cars.

[racer241]

I had this same problem with an older 4bar that had a torque arm but just a chain on the front and a damper(90/10) angled uphill from the rear forward to the chassis. Car would go straight for the wall on brakes. One night i had to just stop using the brakes so i could survive the race. We took angle out of the damper and it helped, then eventually went to a 6th coil and that finished off the problem. Check the angle on your damper hiked up, i don't think it should be more than 20 degrees ever.

[RacerX10]

I had this same problem with an older 4bar that had a torque arm but just a chain on the front and a damper(90/10) angled uphill from the rear forward to the chassis. Car would go straight for the wall on brakes. One night i had to just stop using the brakes so i could survive the race. We took angle out of the damper and it helped, then eventually went to a 6th coil and that finished off the problem. Check the angle on your damper hiked up, i don't think it should be more than 20 degrees ever.

Thanks, I'll check that when I put a damper on it. Right now it hasn't got one at all

[RacerX10]

Do you guys agree that having the 90/10 in the "damper" position above the rear end will have greater effect at calming this thing down than having it on the front of the LR bird cage as I have it right now ?

[MasterSbilt_Racer]

Do you guys agree that having the 90/10 in the "damper" position above the rear end will have greater effect at calming this thing down than having it on the front of the LR bird cage as I have it right now ?

If that means you have nothing in front of the cage, I'm pretty sure I disagree with that.

[RacerX10]

If that means you have nothing in front of the cage, I'm pretty sure I disagree with that.

I'm taking your advice and leaving the 90/10 in front of the cage, and adding a 90/10 on top of the rear end.

Will report back results.


Thanks !

[Dirtrunner35]

Getting off the gas too hard and the chassis slamming down causes rear to steer to the left causing the car to go right, turn a little left when this happens. Also like the others said, more compression on the LR shock. I have a mod and a 6 compression on the LR and it does great.