4-bars and chassis stuff

[Ze Colonel]

I am sorting out my LSC 427 Cobra and was wondering if anyone has verified that their live axle rear end is properly aligned with the chassis. I have established the centerline of my frame based on the front and rear suspension component attachements and from this found the true perpendicular line. It is from this P-line I think I should alingn my rear axle housing for zero thrust angle.

I found that the attachment points for the lower bars are not square with the center line of the frame by 1/4 inch which equates to 0.34 degrees for my application. Based on this I need to have the drivers side lower link 1/4 inch ( out of 12 inch nominal) then the passenger side to get the rear end square up with the frame for zero thrust angle.

Not a huge amount but a little larger then I expected. I hope I do not encounter binding of the links with this much offset.



Anyone have experience with such matters?

[392cobra]

Originally Posted by Ze Colonel

I found that the attachment points for the lower bars are not square with the center line of the frame by 1/4 inch which equates to 0.34 degrees for my application. Based on this I need to have the drivers side lower link 1/4 inch ( out of 12 inch nominal) then the passenger side to get the rear end square up with the frame for zero thrust angle.

Not a huge amount but a little larger then I expected. I hope I do not encounter binding of the links with this much offset.



Anyone have experience with such matters?

Interesting about the 1/4".
Your's is the 4th LSC I know of with this difference.Found it on mine first.
I forget now if the lower left link length ended up longer or shorter.
No big deal,just get it square.

After you have everything finished up,( axle square,pinion angle),and take it out for a drive there is one final adjustment you might need.If the rearend wants to go left with spinning the tires ,add 1/8-1/4 turn of preload to the upper right bar.Take preload out if it wants to go right.

[Tim Brewer]

The other day one of my bars had begun to squeek a little. After close inspection, I noticed one of my bars were binding up a little. So I adjusted all of them by 1st measuring the left bars and matching the length of right bars. It took quite a while to do this because when you barely turn one bar, it binds annother bar. Once all the bars were unbound,(as close as they could) and the tops and bottoms were the exact length, I took it for a test drive. First thing I noticed was the streeing wheel was now crooked, and I had to get back under the car and turn out the passenger side bars to straighten things out. So, that meant that something was not square with the 4-bar mounts. As far as being unbound, like I said ,I got the bars as close as they would possibly go. I used to wrench on a sprint car that had radius rods (same as the 4-link bars, only aluminum and much beter), all over the rear and the front as well. When I had them unbound, you could move them with two fingers very easily. Maybe our bars are just kinda cheap and need to be replaced with something much beter.
Tim

[392cobra]

Tim,
That makes you #5.

Here are the rod ends a lot of us are using on the LSC.

http://racerpartswholesale.com/ phone 800-397-7815


QA1
The high strength alloy series features a heat treated chrome moly body, 52100 steel ball, a teflon / kevlar self lubricating and self sealing race. Available in r.h. and l.h. thread.



Rod ends

XMR10 .6250 5/8 - 18 $25.04
XML10 .6250 5/8 - 18 L.H. $25.04




Jam nuts
5800L 5/8" LH $ 1.50


5800R 5/8" RH $.60

You'll need 4 each of everything.