997 gt3 track wheels, 18 or 19?
#61
Drifting
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63 offset is perfect, just remove the 5mm spacer from the hub. -3.4 sounds like way too much camber in the rear, and I don't think there's much benefit, unless you are running slicks. I'd put 1 full degree of positive camber back in. My tires wear perfectly even at -2.5.
Sounds like the front is ready for a big tire, but if you put a 275 on a 8.5" wheel, it will fit really bulgy and fit improperly. I'd put a 9 or 9.5 up there for the appropriate tire. That being said, I've been very happy with a 9" front, and I even run a huge front sway bar, softest rear bar setting and a squatted rear. Essentially, I'm searching for rear grip because I trail the car a lot, and on paper the car should push, but it doesn't.
Caster should be 7.5-8 regardless of ride height because it centers the wheel nicely, but over 8 almost guarantees that it's going to rub in the front.
I don't know what my official frame-measured ride heights are, but the ground to fender arch center measurements are 25.5" in the front and 25.75" in the rear. This equates to very little rake (probably 10-15mm), as I felt rake only contributed to the rear end coming around.
Sounds like the front is ready for a big tire, but if you put a 275 on a 8.5" wheel, it will fit really bulgy and fit improperly. I'd put a 9 or 9.5 up there for the appropriate tire. That being said, I've been very happy with a 9" front, and I even run a huge front sway bar, softest rear bar setting and a squatted rear. Essentially, I'm searching for rear grip because I trail the car a lot, and on paper the car should push, but it doesn't.
Caster should be 7.5-8 regardless of ride height because it centers the wheel nicely, but over 8 almost guarantees that it's going to rub in the front.
I don't know what my official frame-measured ride heights are, but the ground to fender arch center measurements are 25.5" in the front and 25.75" in the rear. This equates to very little rake (probably 10-15mm), as I felt rake only contributed to the rear end coming around.
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I'll back my caster down to 8 as well, remind me when reducing caster how does that change the other alignment settings like toe or camber (if any)?
#62
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I'm running Pirelli DH but I can back off rear camber, I just did it to not have too big of a split between F and R. I need to find some front 9 or 9.5" wheels, when I ditched my CCW's and got the OZ's I didn't realize the fronts were only 8.5 and I was running 235 or 245 so I didn't really care. I just checked and it seems all the OZ porsche wheels are only 8.5 not available in 9" ![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
I'll back my caster down to 8 as well, remind me when reducing caster how does that change the other alignment settings like toe or camber (if any)?
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I'll back my caster down to 8 as well, remind me when reducing caster how does that change the other alignment settings like toe or camber (if any)?
#63
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#64
Drifting
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I run the 315/680/18 paired with a 235/245 and it's not bad, with the 305 the rear is a little looser than I like. How is the balance with the 275/645 and 315/680 DH? Does it have too much oversteer? I already have my front bar at full stiff and my rear bar 2nd hole from full soft. I'd be worried that adding that much more front grip without a 325 or wider would upset the balance.
#65
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I run the 315/680/18 paired with a 235/245 and it's not bad, with the 305 the rear is a little looser than I like. How is the balance with the 275/645 and 315/680 DH? Does it have too much oversteer? I already have my front bar at full stiff and my rear bar 2nd hole from full soft. I'd be worried that adding that much more front grip without a 325 or wider would upset the balance.
Last edited by powdrhound; 05-02-2020 at 12:14 PM.
#66
Drifting
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Since those are 7.2 spec tires, it's set up per the 7.2Cup manual but with a bit more camber both front and rear, -4.1/-3.5. Car is a 996 but suspension is essentially 997Cup but with lower roll centers. Suspension set up naturally depends on many variables to get you to your end goals. I'm on 1700/1800 lb springs but will be stiffening the front another 100lbs and rear another 200 lbs. Front bar is middle on a 5-way and rear is one from full soft on a 4-way. Balance is neutral with a touch of understeer on entry. The extra 100lbs of front/rear spring split should dial that out. Here is a video to give you an idea of the balance. Car is very easy to drive..
https://www.youtube.com/watch?v=Gx2xbkR7VLQ
https://www.youtube.com/watch?v=Gx2xbkR7VLQ
#67
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275 on a 9" wheel will not work, The tire will be way pinched and roll over. It will perform far worse than a 235 or 245 on a 9. In order to get the benefit of the wider set up, you have to do it right. For a 275, 10" wheel is key, a 9.5 at a very minimum.
#68
Drifting
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I can't even find a 9.5" front GT3 wheel, which wheel do you use?
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#70
Drifting
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#72
Drifting
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#74
Drifting
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Ideally the largest Pirelli DH's I can fit. Maybe 265/645/18 front and 315 or 325 680 18 rear
I usually run 245/645/18 front and 315/680/18 rear but want to maximize grip if I can fit larger tires. Problem is only have 8.5" front wheels now.
I usually run 245/645/18 front and 315/680/18 rear but want to maximize grip if I can fit larger tires. Problem is only have 8.5" front wheels now.
#75
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So is the verdict here that 18" is better than 19"?
Is it NOT recommended to go NT01 on 19" stock wheels?
Is it a BAD idea to run 235/35/19 & 305/30/19 NT01?
If on Stock 19" wheels, what's the best tire option for mainly street and a maybe 4 track days/yr?
Is it NOT recommended to go NT01 on 19" stock wheels?
Is it a BAD idea to run 235/35/19 & 305/30/19 NT01?
If on Stock 19" wheels, what's the best tire option for mainly street and a maybe 4 track days/yr?