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BCR
07-04-2011, 11:15 PM
Tires RF and both rears are feathering big time and car is sliding up track at entry then bites then will start to slide again at exit. The car does get onto bars some thru turn.
Running a Limited Modified 2 link solid pullbar 2bbl class.
American Racer g60 tires. Frame is a older imca type with a full frame to lower trailing arm brackets at rear.
Impala front clip.
Total weight is 2550 with driver and full fuel. 100# of lead added to rear.
LS % 53.7
R % 55.1
X % 50.2
Bite = 75# all with driver My weight is 230#
Left rear bar at 30 degree and rt bar at 10 degree
Pull bar is 17.5 degree and long bar to trans solid bar. Mounted at rear end towards left side.
Jbar is just under pinion( next hole is just above ) and have 4 inch rake.
springs LF 650 RF 700
LR 225 RR 200
Shocks LF 4 RF 3-5
LR 6-3 RR 4
Coil over lr in front of axle and RR is slider behind.
Ride height is LF 6 RF 6.5
LR 6.5 RR 7
Tire presure LF 10 RF 13
LR 8.5 RR 11
Car is a tad tight on entry when tacky track but still needs a second to bite. On Dry Slick the car teds to slide up some before grabbing. Then when I am back on the gas it accels great but will slide a tad more rite before straight away and have to lift a little. And the 3 tires are feather bad and wearing out quick.
he car is very competitive and a top runner. Just giving up some time having to wait for the grip and slip .. trying to make up some tenths here so I can finaly win. many top 3 finishes no wins. I am pulling my hair.... EHHHHH.

washeduptoo
07-05-2011, 05:33 AM
Have you tried moving the jbar up on frame some and giving it a little more rake, maybe 1/2 to 1 inch? Maybe a little more air pressure? A couple of things to try if you haven't already and good luck.

powerslide
07-05-2011, 09:21 AM
you need to go up on RR tire pressure try around 14. Or have a crew member watch in the turns and make sure it isnt rolling under. I would guess w/ 11pds it will be rolling under but gauges differ so have a guy watch in turns. No grooves on the sidewalls.

rubbinsracin
07-05-2011, 02:34 PM
are you driving the car to hard into the corner which is causing the slide in the slick? maybe if you slow down you will actually go faster by staying straighter when the track goes away?

first thing i would try is to raise up the jbar on the frame. go to maybe 5-6" rake. maybe soften the RF spring in the slick a bit to allow the RF to stick on entry?

BCR
07-05-2011, 02:43 PM
i could be driving in a little hard but the car will still slide up some at exit too. thats what is a little puzzling to me. If I drive in a little slower the car is tight thru the middle big time.
As for the right Front spring. Already have frame notched out for tie rod clearence and plenty of travel. Only have an Inch of shock travel left at best.

mod71m
07-05-2011, 05:11 PM
It sounds like the car is just too tight overall and you are driving the car into the corner harder to help get the car around the track.

Try dropping 50 to 100 lbs on the LF spring rate and move the pull bar about 1/2" or so to the right. Then work with the RR bar angle. I would give the spring and pull bar a try first, then raise the RR bar as needed to get the car loose enough so that you can drive the car into the corner without sliding the rear tires.

Dirtrunner35
07-05-2011, 08:53 PM
What is your wheel off sets and is your rear end square in the car ? Rules that have a solid pull bar bites.

BCR
07-05-2011, 11:01 PM
The wheels are 3 offs except rr 4 off and play with spacers.
The rear has leed in the R about 1/2 inch to try and free it up some at entry and thru turn.

washeduptoo
07-06-2011, 05:27 AM
If your leading the rr, that should tighten up the car, you would need to trail the rr to loosen up the car. JMO and good luck.

BCR
07-06-2011, 09:45 AM
Sorry, I meant Trail RR. The RR is further back. Brain Fart there..

Dirtrunner35
07-06-2011, 09:12 PM
Trailing the RR will loosen car on entry, square it up

Toywagon
07-12-2011, 09:45 AM
Im really late to this topic. But if im reading it corectly and the RR is a 2 link clamped birdcage, the spring behind on the RR really tightens that setup OFF throttle.

If your driver is having to shake the car loose to get it to turn on dry slick, hes blown his entry and having to wait on the car to catch again.

Jim