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hunterracing
09-21-2015, 06:50 AM
Would less angle help gain more traction on very exit of track and hold it longer down straightway and not bust them loose? Brassmonkey medium biscuit travel bout 1 1/4 middle hole rearend 16 to 17 degrees

washeduptoo
09-21-2015, 07:23 AM
It might help with instant traction, it should give more traction down straight. I don't know what brassmonkey biscuit are, but what do they say travel should be with that biscuit? You have preload in it? Is it mounted in front of center line, at center line or behind center line of rear end? Just some things to think about.
Best of luck

hunterracing
09-21-2015, 09:06 AM
Medium bushing mounted in front of housing calls 1/4 I put more in Saturday didt really help.. So would raising on housing and frame be better or lowering on housing and raising on frame a hole or two be better more momentum track

washeduptoo
09-21-2015, 10:25 AM
Try one end at a time in you can to see what it does, around 14-15 degrees might help you. How many bushing bar is this and are they small or the very large bushings?

Confused?
09-21-2015, 02:07 PM
Lowering it on the housing "softens" the rate and raising it "stiffens" the rate of the biscuits. It changes the leverage ratio on the pullbar.

hunterracing
09-21-2015, 03:03 PM
But lowering will take some angle out which should make traction last longer correct but also have more leverage

JustAddDirt
09-21-2015, 03:17 PM
But lowering will take some angle out which should make traction last longer correct but also have more leverage

yes you are correct, and no you are not correct.
If you lower the pull bar mount on rear end, you are effectively softening the rate of the pull bar, and taking leverage away from it.
if your pull bar is traveling the proper distance, like 1 3/4-2 1/4" then you need to be moving up and down on the chassis, not the rear end.
I have moved up pull bar on rear end and chassis mounts over 4" since the beginning of the year, and each time I have moved it up my traction has increased. but there is a limit.
depends on spring, or biscuit rate, length of pull bar.
I am at 18º on pull bar angle.

hunterracing
09-21-2015, 03:23 PM
I'm middle hole now and bottom hole frame traveling 11/4 on biscuit 5 inch long but that's what there calling for on travel

stock car driver
09-21-2015, 03:57 PM
raise on rearend will give you more instant traction when first on the gas... but it can run out on the straight.

18 degrees is where I run, my old car liked 22.

washeduptoo
09-21-2015, 04:02 PM
How long is your pull bar hunterracing, we're running a long pull bar with 14-15 degrees of angle. JAD, Confused and SCD are correct and have provided me with excellent information in the past. Best of luck

hunterracing
09-21-2015, 04:31 PM
34 inches long

washeduptoo
09-21-2015, 05:05 PM
Is your pb at the front all the way to the left, what about on the rear end? One thing we have found with the long pb for us it also affects how a car handles.

hunterracing
09-21-2015, 05:18 PM
Almost in both

washeduptoo
09-21-2015, 06:21 PM
If your thinking your biscuit might be soft or hard, you could move the pb down on rear end or up. Might save you from buying different biscuits. Just a thought.

dirtracer07x
11-02-2015, 03:52 PM
dont mean to hijack this but do the same priciples apply for a solid pull bar on a bmod? i have really been wondering about this. we have to keep ours within 1in of centerline of driveline. 1 more question on my lower link where they mount to the rearend there are 2 sets of holes about 1in apart how does the leverage change the car when its a 3link with solid pull bar?

Confused?
11-02-2015, 05:17 PM
About the angle, the same basic principle applies to a solid bar. One thing to remember, the more angle, the more UNloading at deceleration. That's what causes wheelhop when getting out of the throttle.

Lizardracing
11-04-2015, 04:17 PM
I think the reason why the myth comes about when people say it "runs out of traction" is two main reasons. The first being the spring softens the hit on the tires making mid corner feel better to the driver. The other reason being the spring collapsing under load changes the anti squat characteristics at mid corner till the weight of the car catches up with momentum at about mid straight and the spring expands again changing the Anti-Squat characteristics. It's a dynamic thing that gets removed with a solid PB. Basically put, the solid PB doesn't allow the axle to wrap up and soften the load on the tires till mid straight. You can do that with your foot however.