hey guys, i got a '66 El Camino i'm workin on here. I re-did all the suspension, polyurethane busings, stiffer and lower springs, hi-performance shocks and 1.25", 1" sway bars. The question is, will 17" rims make the car ride too stiff? My dad says i should get 15's so the sidewalls will absorb more of the road but i keep tellin him that it won't be that bad with the 17's. Will the ride be way too hard on the 17's? Thanks guys, need some more opinions

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First you have to define "Too Stiff." Ride quality is a very subjective measurement. What are you willing to live with? I would say that the 1-1/4" front bar will be a little too big. What is the spring rate of the springs that you installed? Stiffer and lower springs doesn't say much. Hi-pro shocks? What kind? As to the 17" rims...depending on the tire width, yes the car will ride rougher with lower aspect tires, and you will pick-up more road noise. The ride quality of tires is directly proportional to the air volume that they contain.

I think that your 1-1/4" front bar and polyurethane bushings will contribute more to the ride harshness than 17" rims, plus if you want to upgrade to big brakes, you are going to have to ditch the 15" rims anyhow. One more thing that I might mention is that it is becoming very hard to find good performance tires in the 15" size that are our diameter. You have to go to at least a 16" rim to get decent tires anymore (decent tires being "Performance Tires" with a higher than "H" speed rating).

My roommate has a civic (I know I know) with 17's, and I ride with him pretty often. He just switched tires recently, same size and everything, different brand. Made a huge difference in the roughness of the ride, so the stiffness of the tire has to be considered as well. Of course, it might not matter as much if you have more than an inch of sidewall and your suspension isn't as stiff as his (I don't think old cars get that stiff).

It isn't the wheel diameter that creates the harsh ride. It is the ratio aspect of the tire. A 60 series 15 inch diameter tire will not ride any better that a 60 series tire on a 17 inch diameter wheel. The issue is the amount of air available to cushion the impact of any bump in the road. In fact, the 17 inch would have the potential for a better ride as the same 60 series tire on a 17 inch rim would have a two inch bigger diameter and will roll over the same size bump smoother.

With that said, if you are looking for a 26 inch diameter tire in both a 15 inch and 17 inch wheel size the 17 inch will ride harsher as you will need to go to a lower tire profile to keep the 26 inch diameter, in effect losing one inch of air cusion (top and bottom).

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Redrum (or Mike)

68 Corvette - 383 CI, 427 HP, 700R4, 12.56 @ 108 MPH
69 SS Chevelle - 502 CI, 610 HP, 2004R, 1320 unknown
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