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streetk14
03-21-2020, 07:06 AM
Hey guys. This has got to be my first post here in close to a decade. Sold all my first gens, and got away from older project cars for a while. Anyway, I picked up a 68 Firebird from a long time friend last fall, and have been working on making it a nice driver. Now to my question:

The car has Global West upper control arms with del a lum bushings. These have been on the car since probably 2004. The current lower control arms are stock with poly bushings. I’m looking to upgrade to a set of tubular LCAs, but am trying to figure out my best option. It’s really between DSE and Global West. The plan is to just run a standard coil spring.

So from a geometry standpoint, is there a problem going with DSE? It seems their lower arms add additional caster, but is that it? Will I have problems using the GW upper with DSE lower? Anyone know how much caster the DSE lowers add?

Thanks guys. Feels good to be back.

79T/Aman
03-22-2020, 07:29 AM
control arms do not change the geometry, the parts don't know what sticker is on other parts, but my advise is to check if either one of them has positive caster built into the lowers, that would help with tire clearance.

red67camaro
03-22-2020, 08:27 AM
I agree. If you add caster, in other words move the upper ball joint toward the rear in the usual fashion, the tire will eventually begin to rub the rear of the fender well. If the lower control arms add caster by moving the lower ball joint forward, it will help in this respect and allow you to run more caster should you so desire. As 79T/Aman said, the parts don't know what sticker is on other parts.

pitts64
03-23-2020, 01:51 PM
The DSE control arms are a work of art. I like how they control caster by keeping the upper control arm straight and just sliding it forward and back. That way you don't have to pile shims on one bolt and have the upper control arms changing caster at different rates during cycling..

My second choice would be SC&C. Mark uses the superior Howe ball joints and has them in a longer size at .9 and .5... This corrects the back word camber issue while shifting the lower ball joint forward adding a half degree of positive caster. I have his Stage three set up with a Lee box on a 69 el Camino (427) and its the greatest car I have ever driven!!

Global West always reminded me of Spark O Matic lol....

streetk14
04-01-2020, 08:53 AM
Thanks. I already have tight clearance near the rear of the fender, so an arm like DSE that moves the lower ball joint forward is what I’d want. Anyone know exactly how much caster the DSE arms add? Trying to figure out if I’ll have too much with the GW uppers. I think I’m around 5 degrees right now.

Also, has anyone here used the Ridetech lowers? Considering doing those and their coil overs. They also move the lower ball joint forward.