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dfhotlm33c
11-23-2011, 11:22 AM
Going over details of car to prepare for next year:

Front lowers: They are stud mount with heim at the crossmember. The heim is placed somewhat forward of center of the crossmember with unequal length spacers (short spacer in front, longer in rear). This puts the lower at a bit of an angle in relationship to the steering rods when wheels point forward. Is there a purpose behind this arrangement? Should the heim be in the center of the crossmember? Is this arrangement set up to place the lowers perpendicular to the centerline of the frame? I can't imagine this location would have any effect on Ackerman or bump steer...

Just a curiosity question. If the chassis builder (Toma Johnson) set it up that way, I'm sure there's a reason..and I know I could ask him, but he's a darn difficult man to get ahold of!

EAMShater
11-23-2011, 12:11 PM
I imagine it's a caster thing..

dfhotlm33c
11-23-2011, 12:39 PM
I thought the same thing...but then considered that changing that location, and thus the angle of the lower wouldn't change the relationship between the upper and lower ball joint, and thus would not change caster, as the lower strut wouldn't move...is that wrong?

EAMShater
11-23-2011, 02:31 PM
I thought that as well after I posted. Unless it just gets the conrol arm closer to one end of the car or the other to set the lead in the front ent without gaining too much caster. As in if it's further forward you dont have to pull it as far forward in the front with the strut rod to get the correct lead in the front end and thus screwing up your caster.. Idk if I explained that well enough but in my head I know what I mean lol. If you dont know what I mean by lead in the front end I mean the rf is about and 1/8th to a 1/4 of an inch further forward on the chassis than the lf. to do this you shorten the strut rod on the rf which increases caster. to offset that they may have offset the shims to one side or the other so that you can have the correct lead and not throw the caster all out of whack. On my 09 BWRC I run the rf forward about 3/16ths to help it turn on entry..