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twisterf5
08-20-2012, 11:15 AM
we have changed to a steel head and run
LF 500
RF STANDARD DOUBLE STACK
RR 225
LR DOUBLE STACK
J-BAR 1in below pinion 8 1/2 rake
08 barry wright copy with extra bar and shock hole but every thing is the same short of the more adjustments.
it is to free and rotates to fast in the middel which end up spinning tires from the middel off. the dryer it get the worse it gets. wet or tacky it is bad fast but once it slicks off it is junk.tried ajusting double stack and bar angels but same results. talked to afco this morning they said to get rid of the double stack. but they are the ones that steered us in the direction.
can any one give some better advice on if it is the double stack or maybe something that i am over looking. thanks

TUFFY
08-20-2012, 11:33 AM
Lose lr stack, keep rf....

twisterf5
08-20-2012, 11:45 AM
it is also pulling the left front off the ground to mutch. afco said thr RF was doing that but that realy did not make sence to me this car does have 10in of drop in the left rear not sure if that is too much.

dualdj1
08-20-2012, 12:00 PM
what springs do you have on your stacks?

twisterf5
08-20-2012, 12:05 PM
Lr 400 top 200 bottom
rf 400 top 700 bottom

MasterSbilt_Racer
08-20-2012, 01:48 PM
Too much left side weight? Too much rod pressure or damping in right side shocks? Rear not square? short lr upper? too much rear brake? etc etc

Could be a lot of things...

How are you measuring drop?

twisterf5
08-20-2012, 02:53 PM
Rf 3.5r 4c
rr 3.5c 5r afco silvers
left side is high 54.5 best 55.1 normal 275lb driver no lead 2450 at 55% rear fuel cell can be slid.
Rr is 5/8 forward
drop is going off some of the pics we have off body line. 7 to 8in in the shop
4 to 5 rf travel
3 rr travel
lrf 6.0 gas set at 100

lrb 6.2 non gas
right side 60lb
lf 90lb
RODS ARE 17.5 TOP 15 BOTTOMS GIVE OR TAKE FOR TRAIL

Egoracing
08-20-2012, 03:20 PM
Dry slick I like to be 52-54 depending on how bad it is. 55 is a little high and will keep the left down. You are driving off of the RR and the RR 5/8 forward may be the issue. In the tacky the LR can over drive the RR but in the slick the LR is giving up. Is the LR tire chunked out or showing alot of wear?

hpmaster
08-20-2012, 03:32 PM
Lr 400 top 200 bottom
rf 400 top 700 bottom

On the right front flip your springs so the 400 is on the bottom and 700 is on the top in the dry slick. Try a 16" 150lb. on the left rear and then try a heavier right rear spring if the first two things don't get you there. The RR 5/8 forward? Almost every car I have had ran best with the right rear back slightly.

MasterSbilt_Racer
08-20-2012, 04:20 PM
I don't know how you measure the lr ride height, but jack the car up under the driver seat until the lr tire just comes off the ground. Your ride height measurement should change by 5.5" or so when the limiter is tight. You may have shims on the underrail or a chain.

twisterf5
08-20-2012, 04:56 PM
no right side chain on right now. body just infront of tire mark rim jack it up and measure. we are getting 7. 8 if some one pushes down on rr bumper. but from the pics looks more like 10
going to put a 450 on RF and a 200 LR. just talked to a friend that was at the track. he said car looked perfect down straits and in rolled over and hooked up but when it hit the middel it came around like a spinning top. and that is what i feel but nothing bottoming out shocks look good. he is thinking that maybe it hits the second spring on rf and is pulling lr off ground. we both just looked at the tires and you can not tell they have been run.let me know what you think.

MasterSbilt_Racer
08-20-2012, 05:03 PM
If your lr tire is dropping 8 inches, that is way too much! That would give you tremendous loose roll steer.

twisterf5
08-20-2012, 05:20 PM
that is what i am thinking too . going to put chain with yellow biscuit back on what do you think about getting rid of the double stack. just wondering if chain is back on and it is the rf springs that it would pull lr off ground.

hpmaster
08-20-2012, 05:29 PM
On a right front stack of 400lb and 700lb the rule is tacky use heavy spring on bottom, slick use light spring on bottom.

twisterf5
08-20-2012, 05:33 PM
On a right front stack of 400lb and 700lb the rule is tacky use heavy spring on bottom, slick use light spring on bottom.

don't think the slider would work 400 is 5 inch i under stand the reason behind it. will have to turn them around to check it out.

hpmaster
08-20-2012, 06:03 PM
I know the slider does work better with the longer 700lb on the bottom and the shorter 400lb on the top, thats what AFCO seems to sell everyone, BUT that set up only works only on the stickyer tracks, not the slick and causes a push from the apex out as the 700 takes over too soon for the slick. Those springs are on my car right now so I can't measure them exactly but I think it is like a 4" or 5" 400lb and an 8" 700lb from AFCO. I have gotten the AFCO to slide and work well with the shorter 400lb on the bottom in th past, but it is right at the bottom of the shock body and you need to make sure the longer side of the nylon slider is pointed up.

The last 2 years on slick I use a Hypercoil 7" 400lb on the bottom and a Hypercoil 6" 700lb on the top as it lets the slider have more contact with the shock body than the AFCO set up. Always watch those dang lock rings as they can and do move.

grt74
08-20-2012, 10:38 PM
I have worked on this stuff a ton,so ill give you my experence,think about it if its just the middle i would adjust the lock nut some,this is whats happening,your car is going in the corner great but as soon as you pick the gas up its real free until it gets back on the big spring and then drives the car forward but by then the car has rotated to much and it shoves u to the infield,the fix,shock,adjust the lock nut,or get off the stacked setup and go to a standard spring,the stacked setup is not for all tracks and your shock is a huge factor in this setup,good luck,also i would just work on the rf first,just my 2 cents

Ramsey22
09-07-2012, 01:09 PM
Decrease your stack nut distance...Pull some rebound out of RF shock...You need your car on that stiffer spring sooner!