6" beam...possible to get good handling?

[Smitty27]

I have used a combo of different beams over the years, some with towers, some without. I had a 5" shockless that handled beautiful...just didnt ride all that soft. A 6" is not all that different than a 5. Is it possible to have a 6" track well and not have bump steer effect? Anyone out there with a 6" or greater that has a tracking car that isnt all over the road when they hit a bump??

Thanks!

my goal is to get the wheels back under the fenders. Disc brakes, spindles, and wide wheels with wide tires brought them waaay out.

[Marc]

The shorter the tierod, the more bump steer you'll have. Setting things up so the tierod stays as close as possible to horizontal through the normal range of suspension travel will minimize changes in its effective length; you also have to take into consideration that the control arms move in an arc so as the suspension cycles they get further/closer to the steering box. A stock-width beam at stock ride height is a pretty good compromise, but as you depart from stock dimensions attention must be paid to avoid excessive bump steer. Going to a center-load rack & pinion setup will give you tierods that are longer than the short one on stock steering, but it's not a simple matter to mount the rack in the right position to minimize bump steer.
Note that while a narrow beam will help to tuck wide tires under the fenders, it only worsens the clearance between the rear of the tire and the front of the pan when the wheel is turned so you often end up sacrificing turning radius - sometimes wider fenders are the better solution.

[jgm_72]

58forumpic.JPG

This car was running a 6.5" narrowed beam. I had just about full turning radius with minimal rubbing on the inside, but it did rub pretty well on the headlight buckets. It had minimal bump steer due to the fact p.o. had it 1/2" off the ground (litterally!) so the roads limited suspension travel. A cross steer setup would eliviate bumpsteer. One tierod from the box to the passenger side spindle, them one rod from pass spindle to driver spindle. A handful of air ride equiped vws are set up like this, seems to work well. On the square Im building I will use either a rack or cross steer. Also if your car is really low or sits on a rake (front lower then back) caster shims can make a world of differance. Good caster settings help a car feel more stable and not so twitchy.

[Marc]

One of my circle-track competitors used to run a kart steer setup, he drilled out the RH steering arm to take a long bolt and used stacked Heim joints at that end. You still need to get the link from the Pitman arm close to horizontal to minimize bump steer, but this does make for the longest possible tierods. That RH side becomes a single point for catastrophic failure, so if you choose to go this route do it right...

[Smitty27]

Those are both good ideas. Jgm, do you have any links or pics to anyone that has done this? I have seen one somewhere but can't remember. I dont see why it wouldnt work.

[Marc]

On the Pitman arm, where only one Heim end needs to bolt up, you can use an adapter (Sway-a-Way #6240) rather than drill out the tapered hole.