My caster mod (with pictures)

[picklito]

Originally Posted by BMERDOC

If 1/4" is worth 1° on the bottom why not machine the uppers 1/8th" to have the extra .5" movement to equalize caster on both sides?

Not sure I'm following this. 1/8" (where?) equals .5"(where?).

Uppers back is a good idea, too. Before I found these threads I was only thinking of lowers forward cuz I also wanted to move the wheel forward in the well, mainly for cosmetics. Obviously, uppers back would negate a little of this, but I'd take 6 degrees over a perfectly centered wheel!

[BMERDOC]

Originally Posted by picklito

Not sure I'm following this. 1/8" (where?) equals .5"(where?).

Uppers back is a good idea, too. Before I found these threads I was only thinking of lowers forward cuz I also wanted to move the wheel forward in the well, mainly for cosmetics. Obviously, uppers back would negate a little of this, but I'd take 6 degrees over a perfectly centered wheel!

I probably shouldn't include myself in the conversations while I'm half asleep on the couch. Now I need to go back and re-read everything I wrote.

I have been thinking about elongating the upper cross shaft locating holes for finer adjustments, leaving the shims only for camber adjustments (1/8" of motion would equal .5 degrees of movement). I need to go back and look over your math and Scoti's alignment numbers.

[69gmcc10]

Originally Posted by BMERDOC

I have been thinking about elongating the upper cross shaft locating holes for finer adjustments, leaving the shims only for camber adjustments (1/8" of motion would equal .5 degrees of movement). I need to go back and look over your math and Scoti's alignment numbers.

I spoke with an old hot rodder/racer about this the other day about this and he said the uppers see so much force under breaking that it would probably shift. My uncle was a front end mechanic for chevy for 30 years. I told him what I was doing and the upper arm shaft idea and he suggested to fine tune the uppers he would unbolt the shaft from the studs and twist it. He said he used to do it all the time and each turn on the shaft is just under 1/4" forward or backwards off the top of his head.

[BMERDOC]

Originally Posted by 69gmcc10

I spoke with an old hot rodder/racer about this the other day about this and he said the uppers see so much force under breaking that it would probably shift. My uncle was a front end mechanic for chevy for 30 years. I told him what I was doing and the upper arm shaft idea and he suggested to fine tune the uppers he would unbolt the shaft from the studs and twist it. He said he used to do it all the time and each turn on the shaft is just under 1/4" forward or backwards off the top of his head.

Was he referring to twisting the upper shaft in the end caps? It would kinda make sense. While installing them you want the caps to go on equally and tighten them down from there. The only problem with this is that you wouldn't want to have the the shaft improperly engaged in one cap (front in this case). I will agree that it is worth a closer look. Im not so sure the shafts would shift if properly torqued but his idea is free and machining isn't. The front suspension on my truck is disassembled at the moment and I was just about to order new u-bolts to reassemble it so it I do think its a good time to investigate the possibilities. Its been a while since I've even thought about this whole thing.

[69gmcc10]

Originally Posted by BMERDOC

Was he referring to twisting the upper shaft in the end caps? It would kinda make sense. While installing them you want the caps to go on equally and tighten them down from there. The only problem with this is that you wouldn't want to have the the shaft improperly engaged in one cap (front in this case). I will agree that it is worth a closer look. Im not so sure the shafts would shift if properly torqued but his idea is free and machining isn't. The front suspension on my truck is disassembled at the moment and I was just about to order new u-bolts to reassemble it so it I do think its a good time to investigate the possibilities. Its been a while since I've even thought about this whole thing.

Yes, twisting them in the caps...After I talked to him and was thinking about this, I also was concerned about moving the shaft far enough forward that it would bottom out in the front cup during suspension travel and cause issues. Just need to pay attention.