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rubbinsracin
07-27-2012, 11:28 PM
So we are in the process of putting a new to us car together and going from old to new we noticed the rear 4 bars require the hiem spacers because the frame mounts are spread apart. Why did chassis manufactures start to go to this?

racer2e
07-27-2012, 11:52 PM
I was told It is so you can toe the bars in or out to change indexing without changing drive angle or steer very much.

jedclampit
07-27-2012, 11:59 PM
So the heims /bars don't interfere with the frame in thier range of motion and bind or break with almost any possible setting.
Also different length spacers car be used to alter rear steer and birdcage loading with chassis roll.

MasterSbilt_Racer
07-28-2012, 07:11 AM
And single-shear mounting is poor design.

Matt49
07-28-2012, 08:24 AM
You may also need a reducer bushing as the heims should be 5/8 inch and the holes on most new cars (with more adjust-ability) are 1/2 inch.

racin6mod
07-29-2012, 11:06 AM
So the heims /bars don't interfere with the frame in thier range of motion and bind or break with almost any possible setting.
Also different length spacers car be used to alter rear steer and birdcage loading with chassis roll.

this is the best answer. they used to try and have the mounts to close together and the jam nuts would hit the mounts or the heims would hit. it never made much sense to have a heim joint that could only move 2o percent of it's travel limits.we had a lm that you could jack up and the bars would bind and raise the wheel off the ground before the shock maxed out on travel.