Car Tight Through Center

[Ridin Dirty]

I am racing on a tight cornered track that starts out with some bite and gets dry slick on one half and tends to keep some bite on one half. The track configuration really calls for the cars to need a good amount of forward bite because you slow down so much in the corner.

The car is pretty good early but as the night goes on i begin to pick up a push in the center. The car turns in well. I can get the car to circle well if a get the rear out but when i do this a pedal the car off the corner and everybody pulls away from me down the straight. Here is what I am running on the car now.

RR 225 on 3/5
LR 225 on 6/3
RF 400 on 3/5
LF 550 on 6/3
5th 300 at 38" on 3/5

I am running 80 - 120# wedge
L% 54.5 w/driver
R% 55.5 20 gal fuel
Stagger 4" rear, 1" front
LRT bar is 1 hole from top
LRB bar is 3rd hole up
RRT is in Top
RRB is in 1 hole from bottom
J-bar has 5" split and is 1 inch below pinion.

I need some help to get the car to turn better in the center. The car starts to push even before I am in the gas. I can turn the wheel and it feels like the RF just slides out from under me.

I have been watching the cars that I race against closely to see if I am not driving the corner correctly and they seem to be more out of shape than I am, but they go down the straightaway, especially the Rayburns. I in a Rocket and they are what are winning the races.

[billetbirdcage]

Let me take a guess here:

The car is tight or won't finish turning right before you pick up the throttle? If that is the case that is a common problem with the low bite set-ups, I'd use a high wedge set-up in that case (tight on late coast). Try increasing the bite to at least 160 and up to 190.

[Rocket Bonehead]

If you're running a steel block, or all steel engine, stiffen the LF to a 600 or 650 to help the car get over. Your description is a common one I hear when the RF is too stiff. I wouldn't want to go any softer than a 400 with a steel block or steel engine (on a Rocket).


If you are running all aluminum, soften the RF to a 325 or 300 (12" spring). If it is a blue front car, go with the LF spring change and go no lower than a 400 (make sure that's a 12" spring if you're on a blue front).


I would also look into adding 1/8" to 1/4" more static steer.



You can try the increased bite, but you'll shove the nose like a dump truck with 225's across the back. If you're going to increase the bite above 130lbs, I'd soften the LR to a 200 or 175.



If the car starts to get tight on the throttle, at a track like you describe, try running the LRB rod in the 4th hole up (will need a 'swing-arm' or "bent" bar for the LRB rod).



RB

[MBR675]

Add some gear to the car. Somtimes the problem isn't always the setup on the car.

[Clem21]

.....If you are running all aluminum, soften the RF to a 325 or 300 (12" spring). If it is a blue front car, go with the LF spring change and go no lower than a 400 (make sure that's a 12" spring if you're on a blue front)......



RB

Why are you using a 12" spring on the RF? I'm not questioning, I just don't know the answer.

[billetbirdcage]

I think he is refering to making sure you are not coil binding the spring. Something will eventually stop the travel on the RF: Either bottoming out the shock, coil binding the spring, running out of ball joint travel, over traveling the tie rod ends, or ETC.

A 12" spring will generally have more travel then a 10" before it coil binds. Heavier springs have thicker wire diameter so for the same number of coils and hieght they will have less travel (due to the smaller gap between the coils) before they bind then a softer spring does. But generally the softer spring will travel farther due to the softer rate so alot of times it is a wash.

This is something you need to watch on a 10" spring but on a 12" spring you can usually just forget about it (but it can happen).

[IDOXLR8]

WHat year and front end car?

"The car starts to push even before I am in the gas"
Too tight on entry, you can't slip the rr?

Try one or two of the following:
Lower lf spring rate .
Take some rake out of the ph bar .( Where you at on frame?)
What are your spacing adjustments on the pinion plate for the ph bar.
Raise the lr lower up 1 hole.
Add an inch or 2 of step.
Move rear end to right depending where you are now.( 16.25~15.75 ?)

If the car is not aimed where you want it go..;). its gonna go where its aimed!

[Ridin Dirty]

I think my problem may be with shocks. The 300 rf helped, but I am using the brake pedal to make the car transfer weight to the RF. I have to brake hard in midcorner being careful not to slide the car and start the transfer to the RF. I f i roll into the corner the car pushes like a dumptruck on or off gas in center. the car was better on a twin tube AFCO 3-5 than with M2 on slick setting with 20 psi gas. What are some shock tuning option I cal work with? I cannot get any less compression out of the M2 and have been told that I really don't want to go with less gas pressure.

[IDOXLR8]

Move rear end to right depending where you are now.( 16.25~15.75 ?)