Why less camber with larger wheel diameter?
11-05-16, 08:35 PM
#26
I bumped the size from 255 nt01s to 275 RC1s, so sadly no direct comparison but yes I do like these tires better. They do not like being overdriven. If you slide them, you need to back off for a couple corners and let them cool off. The NT01s let you get away with a bit more of that, and driving them on the edge or slightly over it seemed fastest.
For the 2nd set of RC1s I'm running them on one inch wider wheels than before. (lookatme would be happier) and things are a bit more taught now. It seems to have picked up a bit of speed. (Ran my best time ever at a track I hadn't been to in a year.) I actually get no tire rub now on the rear trailing arm and the tire is a couple mm inboard of where is was with the narrower rims.
Yea we did go through a lot of this.
For the 2nd set of RC1s I'm running them on one inch wider wheels than before. (lookatme would be happier) and things are a bit more taught now. It seems to have picked up a bit of speed. (Ran my best time ever at a track I hadn't been to in a year.) I actually get no tire rub now on the rear trailing arm and the tire is a couple mm inboard of where is was with the narrower rims.
Yea we did go through a lot of this.
Last edited by LargeOrangeFont; 11-06-16 at 07:53 AM.
11-05-16, 10:43 PM
#27
I just measured the wear on my Hoosiers today when I was putting them away because LOF made my curious...
the fronts are wearing slightly more on the outside with -3* (already changed to -3.5*)
rears are wearing slightly more on the outside with -1.8*.... I don't think I'm going to touch that to try to maintain forward bite.
the fronts are wearing slightly more on the outside with -3* (already changed to -3.5*)
rears are wearing slightly more on the outside with -1.8*.... I don't think I'm going to touch that to try to maintain forward bite.
11-06-16, 10:20 AM
#28
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you're welcome! sometimes we can overthink this stuff.
it could be that the new tires want a different pressure too.
everyone does pressures wrong. the pressure you have changes how much heat you have, and tires are also springs.
so there are two scenarios:
if you're NOT taking tire temps. tires have a spring rate, so make sure the pressures are even when its hot. Hoosier has a pressure vs weight chart, and if your tires don't have that, its a good start.
if you are taking temps, you still want the pressures even, but you can use the pressure to move the temps up or down.
we have found that once you get the temps right, the tires last much longer. the Hoosier R7's ended up at a higher pressure and less camber than our initial setup.
it could be that the new tires want a different pressure too.
everyone does pressures wrong. the pressure you have changes how much heat you have, and tires are also springs.
so there are two scenarios:
if you're NOT taking tire temps. tires have a spring rate, so make sure the pressures are even when its hot. Hoosier has a pressure vs weight chart, and if your tires don't have that, its a good start.
if you are taking temps, you still want the pressures even, but you can use the pressure to move the temps up or down.
we have found that once you get the temps right, the tires last much longer. the Hoosier R7's ended up at a higher pressure and less camber than our initial setup.
11-06-16, 12:27 PM
#29
you're welcome! sometimes we can overthink this stuff.
it could be that the new tires want a different pressure too.
everyone does pressures wrong. the pressure you have changes how much heat you have, and tires are also springs.
so there are two scenarios:
if you're NOT taking tire temps. tires have a spring rate, so make sure the pressures are even when its hot. Hoosier has a pressure vs weight chart, and if your tires don't have that, its a good start.
if you are taking temps, you still want the pressures even, but you can use the pressure to move the temps up or down.
we have found that once you get the temps right, the tires last much longer. the Hoosier R7's ended up at a higher pressure and less camber than our initial setup.
it could be that the new tires want a different pressure too.
everyone does pressures wrong. the pressure you have changes how much heat you have, and tires are also springs.
so there are two scenarios:
if you're NOT taking tire temps. tires have a spring rate, so make sure the pressures are even when its hot. Hoosier has a pressure vs weight chart, and if your tires don't have that, its a good start.
if you are taking temps, you still want the pressures even, but you can use the pressure to move the temps up or down.
we have found that once you get the temps right, the tires last much longer. the Hoosier R7's ended up at a higher pressure and less camber than our initial setup.
I'll check out that pressure vs weight chart and start there before I reengineer my alignment.
Last edited by LargeOrangeFont; 11-06-16 at 12:30 PM.
11-06-16, 04:20 PM
#30
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I feel I'm getting good life out of the tires - over 20 hours of decent grip before they start to fall off notably. These seem to like 34-38 hot. I run between 35-37 hot depending on the track. If I run more pressure the grip starts going away as I approach 40 PSI hot. I do take tire temps. They are within 20 degrees across the tire by the time I'm in the pits any out of the car.
I'll check out that pressure vs weight chart and start there before I reengineer my alignment.
I'll check out that pressure vs weight chart and start there before I reengineer my alignment.
