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Author Topic:   pullbar location vs fwd bite
rpm20
Dirt Freak

Total posts: 338
posted August 20, 2005 06:02 AM  
i just picked up some new pullbar plates for the dw8 and noticed it had another set of holes lower on the plate .
this would mount the axle end of the pullbar about 4" above the axle housing.
i was told by the dw rep. mike wedelstadt .....that that location gives better fwd bite.
any opinions or experience with this new lower location anyone????

[This message has been edited by rpm20 (edited August 20, 2005).]

gould
Dirt Forum Champ
Total posts: 730
posted August 21, 2005 10:09 AM  
more angle will give you quicker bite off the corner but will not last as long, meaning it might get good bite halfway down the staightaway.

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flyin353
Dirt Full Roller

Total posts: 49
posted August 21, 2005 10:43 AM  
agreed...more angle will give you more initial bite but will un-hook sooner. 1/2 way down the straight the car will (if its lke mine used to be) pitch sideways.

CUSTOMPERFORMANCE
Dirt Forum Champ
Total posts: 1172
posted August 21, 2005 09:02 PM  
Less angle when dry slick wont act as fast but feel hooked up longer down the straight away. Most people dont seem to understand this or are unwilling to try less angle.

rpm20
Dirt Freak

Total posts: 338
posted August 22, 2005 05:10 AM  
well according to mike, running less andgle, like almost level ......gives a lot better forword bite.
hmmmmm...........maybe i will try it out.

GRTWallbanger
Dirt Maniac

Total posts: 196
posted August 22, 2005 11:04 AM  
Asphalt guys run them level.(where traction is not a problem)
What does that tell ya.

[This message has been edited by GRTWallbanger (edited August 22, 2005).]

Kromulous
Dirt Forum Champ
Total posts: 796
posted August 22, 2005 12:31 PM  
I dont think its quite that simple.

Less pull bar angle will generate less anti squat under accelleration. This could allow for more weight transfer, faster and load the springs better.

I generally only run 15*, our car begins to get to rigid on exit if i run to much, and or hops or shakes bad. This tells me that there is to much anti squat.

I believe that you need to allow some weight transfer, and spring compression on the rear springs before the antisquat takes over and makes the car stiffen up. Running a pull bar at say 5* would allow to load the springs easier intially, and then as the rear end compresses it adds anti squat via the angle increasing on the pull bar. Once the anti squat gets to a high enough point, the compression of the rear springs stops as the anti squats gets to high for the weight to overcome it.

Excess pull bar angle also makes a car loose, roll steer wise. Once the rear steer begins to happen the car will want to snap loose. Thats from my expierence.

Low pull bar angle would be way better on a rough track as well, or should be. I have not tried it, as we dont see to many rough tracks.

[This message has been edited by Kromulous (edited August 22, 2005).]

wfoondirt
Dirt Forum Champ
Total posts: 505
posted August 22, 2005 01:17 PM  
Well said krom.

Also when you get alot of angle in the pullbar it will tend to hold the car up, essentially creating a bind in the suspension.

The reason asphalt cars don't run alot of antisquat has nothing to do with not having traction problems.

dirtywrench13
Dirt Freak

Total posts: 324
posted August 22, 2005 03:29 PM  
SO WHAT YOUR SAYING IS,IF THE CAR DOESN'T SEEM TO BE LIFTING AND I HAVE AS MUCH ANGLE IN THE PULL BAR AS I CAN GET, I MIGHT WANT TO ADD MORE SPRING IN THE REAR ON BOTH SIDES? IT'S ROLLING OVER O K AND IS A LITTLE SLUGGISH JUST BEFORE THE APEX OF THE TURN(HE'S WAITING ON IT GOING IN).

Kromulous
Dirt Forum Champ
Total posts: 796
posted August 22, 2005 03:48 PM  
To be honest, i dont know. Do you want lift on the rear?

I would think not, at least not to quickly. I preferr to see the car squat, a little bit, and then go on down the straight then rise slowly.

Maybe Wfoondirt can help with this one.

wfoondirt
Dirt Forum Champ
Total posts: 505
posted August 23, 2005 08:59 AM  
Krom is right on on this one. Reguardless of setup anti-squat requires grip to work. If the rear tires don't grip from the get go then the car won't lift.

One thing that often happens with excessive pull bar angle is that it will serverly unload the rear tires under braking (on asphault it would be seen as wheel hop.) The tires can be so serverly unloaded that the effect will be carried into the apex and cause the drive to have to wait on the tires to settle before getting on the gas. If he gets on the gas too early the tires never have a chance to grip and pretty much kills corner exit. No ammount of antisquat is going to be able to overcome it.

Also if you springs are clamped to the housing alot of pull bar angle will make the rear wheel rate stiffer. This is due to the pull bar triing to rotate the rear end against the springs.


Without seeing your car and knowing the setup its difficult to accurately diagnose problems and I don't like to give misinformation. The setups that are run today on dirt are so far out there that its near impossible to diagnose without seeing the car work.

dirtzone
Dirt Maniac

Total posts: 102
posted August 25, 2005 03:54 AM  
[QUOTE]Originally posted by wfoondirt:
[B]Also if you springs are clamped to the housing alot of pull bar angle will make the rear wheel rate stiffer. This is due to the pull bar triing to rotate the rear end against the springs.

So what ways could you reduce wheel rate?

star1modified
Dirt Maniac

Total posts: 102
posted August 25, 2005 12:07 PM  
move the offset out...run smaller tires...

tlkdlw
Dirt Full Roller

Total posts: 42
posted August 26, 2005 12:32 AM  
The amount of angle is'nt the only thing too
influance lift or anti squit. The closer you get to the rear end housing the easyer it is to lift
the chassis or stop sqat. So I would try the lower hole on the housing

psycho47
Dirt Full Roller

Total posts: 48
posted August 26, 2005 06:14 AM  
The plates I have also have an additional set of hole behind the centerline of the axle. I was told then when the axle rotates it flattens out the pullbar and would provide more forward bite. Is this correct?

rrrrick
Dirt Maniac

Total posts: 192
posted August 26, 2005 10:47 AM  
Psycho,
The plates you have now don't give you MORE forward, but a LONGER forward, basically the best of both worlds,
More angle to help with initial bite off the corner, and as the axle rotates, less angle, to help keep the car hooked down the straightaway



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