Ray, I see your car is a 68 Catalina, are you trying to put C3 spindles on the USA suspension? Could this account for the said difference?
Here's a picture below that could be a clue. 65 Impala above a 63 USA Pontiac. Aside from a smaller dia spindle (65-68) and a taller upper brake backing plate mounting boss, the rusty Impala spindle looks identical to any 65-82 C3 spindle.
And to my eye it does look about .5" more offset from the lower ball joint to spindle flat than the Pontiac part. Mind you, it is a 63 Pontiac part.
So the Impala spindle used in the USA car might just increase overall track width. Which is actually a good thing overall for handling.
But the better bet is to just use a late 60's USA B body spindle and single piston disc brake setup on your 68 USA car. It would assure the correct geometry.
Cheers, Mark
-- Edited by cdnpont on Monday 20th of February 2012 03:54:18 PM
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65 Laurentian post, 67 Grande Parisienne 4 door HT.
I put C3 spindles on my car('66 'Chief),without any troubles, and truthfully they went on true and the car hasn't needed a wheel alignment.It doesn't pull at all and after approx. 1200 miles my tires are showing minimal wear.So as cdnpont has pointed out,the difference must be on our American cousin B body cars.The '65-'68 "B" body spindle share the same part # as the C3 spindle.I have done alot of homework before I went ahead and did the swap. It takes longer to change the lower ball joints than to change spindles. Well worth the time/expense. The stopping power is incredible-I also have C3 brakes on the rear as well.Now that's a different story........
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"No matter how much you change, you still have to pay for the things you've done".
