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      04-07-2012, 11:53 AM   #1
paradocs98
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Tire-to-strut clearance question

This might be a silly question. I think I know the answer but I'd like some confirmation. I have the Dinan Stage III suspension which uses different springs and modified bumpstops, as well as front camber plates, but retains the stock struts. On the track I use a square 18x10" Forgeline with 275/35-18 Nitto NT01 setup. Last season I was running about -1.8 to -2.0 front camber and had no clearance issues. This Spring I had my front camber increased to -2.4.

Yesterday I was replacing my Turner wheel stud kit in anticipation of the new season and I test-fit my track tires to make sure the wheel weights from balancing didn't contact my front brake calipers (BBK). It was then that I noticed the tire-to-strut clearance is pretty tight--can't get a finger fully in the space. When you spin the wheel it doesn't appear to rub, but I wonder if this clearance changes under load/suspension compression at speed?

The other question is--does this clearance or spatial relation between the tire and strut change with camber adjustment? With increased negative camber and the top of the tire moving inwards, does this tire-to-strut clearance shrink? Or since camber adjustments are made at the top of the strut tower, do the wheel and strut change angle together as a unit, thereby maintaining the same clearance relative to each other? It might have been the same amount of clearance as last year, but I just don't remember exactly how close it was before the camber adjustment.

Again, I know the clearance was fairly tight last season but I had no rubbing issues, and driving up and down the driveway yesterday with the increased negative camber didn't seem to create a tire-strut rub, but I wonder if I should have any concerns at speed on the track?

Once again, I can make a single question into a multi-part essay...

Thanks

Last edited by paradocs98; 04-07-2012 at 11:58 AM.
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      04-07-2012, 12:55 PM   #2
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No, adjusting camber will not impact the clearance at the top of the tire for the reason you stated - strut and wheel/tire move together because adjustment is made at the top of the strut.

Fortunately, the worst case loading on a tire is when you are cornering so the top of the tire doesn't deform significantly so the dynamic clearance is basically the same as the static clearance.

If you decide to switch to aftermarket dampers be careful because most damper bodies are shorter than stock and it puts the height adjuster at the same height as the max tire width! I would not be able to use your 18x10 (et27?) Forgeline's on my car.
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      04-08-2012, 09:04 PM   #3
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Thanks for the confirmation!
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      04-08-2012, 09:53 PM   #4
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Quote:
Originally Posted by dbarnes View Post
No, adjusting camber will not impact the clearance at the top of the tire for the reason you stated - strut and wheel/tire move together because adjustment is made at the top of the strut.

Fortunately, the worst case loading on a tire is when you are cornering so the top of the tire doesn't deform significantly so the dynamic clearance is basically the same as the static clearance.

If you decide to switch to aftermarket dampers be careful because most damper bodies are shorter than stock and it puts the height adjuster at the same height as the max tire width! I would not be able to use your 18x10 (et27?) Forgeline's on my car.
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      04-09-2012, 07:18 AM   #5
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Quote:
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Thanks for the confirmation!
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Originally Posted by rldzhao View Post
You're welcome
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