Insalled the 19" Wheels... Real Tight... Now What?
#61
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I just came across this thread, rather topical for me today. First let me introduce myself to the 996 GT3 community. I just traded my 07 997S for a 04 996 GT3. I've got 2 sets of 19" track wheels from the S which have to go. I've also got a set of CCW 18", 9" fronts and 12" rears. Don't have the offsets for them. The fronts look like they will fit fine with 245/40/18 hoosier R6's. On the rears I've currently got 335/30/18 R6's. With the rears mounted it looks like the side wall might be too close to the fender under compression. I'm hoping with 315/30/18 there will be enough clearance. The question I have is does any of you run 315's on your cars. If the 315 will fit and clear the fender, it looks like it may be tight, but with a little more camber than is on the car now it should be okay. The prior owner never tracked the car, so I'm expecting the current camber is only about -1.5.
Any thoughts would be appreciated.
Thanks, John
Any thoughts would be appreciated.
Thanks, John
front 245/35 is better than 245/40
#62
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I run 315 with 11" CCW. As long as the offset on your 12" CCW is good then you'll be ok.
#63
Didn't get a chance to take pics yesterday. Only had time to mount the wheels to check for fitment. The 12" CCW looks like it sits just inside the fender, so hoping when I get a chance to put some old 315's on the wheel it will work. It'll be close. I check wth CCW on the offsets for these wheels. That info is not on their invoice.
I notice from your posts that you're from Ontario. Ever get a chance to drive Calabogie. That's one of my favorite tracks. The last three years I've been up there in July with NER for three days there and three days at Mont Tremblant. Get events!
Mooty, Good point, besides better fitment in the wheel well the 245/35 is closser to the 315/30 diameter. Better for the ABS.
#64
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"Better for the ABS" means to stay close to the factory diameters for front and rear so the ratio of the difference F to R of revolutions per mile stays close to oem . Not to match the front and rear tires in diameter.
With the 315 being taller than the 295 you would ideally want a taller than oem front too.
the 245/35 is not, the 255/35 is closer to oem but again a little shorter, the 245/40 is a better match for the 315 in terms of diameter but being taller than oem can create rubbing issues depending on the height and camber front.
#65
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Never been to Calabogie (this was my first year), but that and Watkins Glen on my list for next year. The car probably knows that track by heart though as it was its home track.
I've been to Mosport and Tremblant.
I've been to Mosport and Tremblant.
#66
Actually no.
"Better for the ABS" means to stay close to the factory diameters for front and rear so the ratio of the difference F to R of revolutions per mile stays close to oem . Not to match the front and rear tires in diameter.
With the 315 being taller than the 295 you would ideally want a taller than oem front too.
the 245/35 is not, the 255/35 is closer to oem but again a little shorter, the 245/40 is a better match for the 315 in terms of diameter but being taller than oem can create rubbing issues depending on the height and camber front.
911SLOW
Then is the 12" wheel will work. Still to be determined with the offset question and fitting it with 315's. Then from an ABS standpoint the 245/40 would work better with the 315/30 rear assuming the front alignment can give me what I want for camber and caster without causing too much wheel well rubbing. This year I won't be making any changes to the stock height. So hopefully the the 245/40 will work.
"Better for the ABS" means to stay close to the factory diameters for front and rear so the ratio of the difference F to R of revolutions per mile stays close to oem . Not to match the front and rear tires in diameter.
With the 315 being taller than the 295 you would ideally want a taller than oem front too.
the 245/35 is not, the 255/35 is closer to oem but again a little shorter, the 245/40 is a better match for the 315 in terms of diameter but being taller than oem can create rubbing issues depending on the height and camber front.
911SLOW
Then is the 12" wheel will work. Still to be determined with the offset question and fitting it with 315's. Then from an ABS standpoint the 245/40 would work better with the 315/30 rear assuming the front alignment can give me what I want for camber and caster without causing too much wheel well rubbing. This year I won't be making any changes to the stock height. So hopefully the the 245/40 will work.
Calabogie is a fantastic track. If you can make the time check out the three day NER event in July. Mosport in on the list this year. One of tracks in the Northeast I've not been to and have been getting some prodding from some of my Canadian and Up State NY friends to get to.
NER also has a three day weekend event at Watkins Glen. Three days are a great way to learn a track.
Mooty & Slow
Back to the tire issue. I'll be running this car almost exclusively on the track and other than rains I'll be running Hoosier R6's, what would be the best tire/wheel dimensions to run?
#69
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For track duty only: the widest wheel you can put under there the better always!
For tires about the same with some attention that some of them depending on sizes and construction of walls you want to stretch them properly on the wheels .
So 12R 9F and 245/40 or 255/35 and 315 or 265 / 335. Now track also means that you don't rally care if it rubs a little or wheel can't fully turn.
Just drive. : )
For tires about the same with some attention that some of them depending on sizes and construction of walls you want to stretch them properly on the wheels .
So 12R 9F and 245/40 or 255/35 and 315 or 265 / 335. Now track also means that you don't rally care if it rubs a little or wheel can't fully turn.
Just drive. : )
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My invoice has some numbers under the "RCONFIG" box and mine are:
1811/850
This means 18" diameter, 11" wide, 8.50" backspacing
I'm not sure what a good backspacing value is for a 12" wheel.
You can measure it yourself. Remove the wheel and put it face down on the floor. Place a straightedge spanning the back of the wheel and measure from the mating surface of the inside of the wheel (the part that touches the brake rotor) to the straightedge. This is the backspacing value and what CCW goes by.
#72
The info should be on the invoice, but it's a backspacing value in inches, not offset in mm.
My invoice has some numbers under the "RCONFIG" box and mine are:
1811/850
This means 18" diameter, 11" wide, 8.50" backspacing
I'm not sure what a good backspacing value is for a 12" wheel.
You can measure it yourself. Remove the wheel and put it face down on the floor. Place a straightedge spanning the back of the wheel and measure from the mating surface of the inside of the wheel (the part that touches the brake rotor) to the straightedge. This is the backspacing value and what CCW goes by.
My invoice has some numbers under the "RCONFIG" box and mine are:
1811/850
This means 18" diameter, 11" wide, 8.50" backspacing
I'm not sure what a good backspacing value is for a 12" wheel.
You can measure it yourself. Remove the wheel and put it face down on the floor. Place a straightedge spanning the back of the wheel and measure from the mating surface of the inside of the wheel (the part that touches the brake rotor) to the straightedge. This is the backspacing value and what CCW goes by.
You're right. Just checked the invoice and it lists a 9.25BS value for the 12" wheel. So 9.25 back spacing. The wheel with the 335/18 fits with no obstructions on the inside. Have to mount the 315's to see if the tire side wall will clear the fender.
Thanks John
#73
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^ it will clear if you have any camber at all. however, you may rub under severe compression. BUT if you run -2.5 or more camber, then no more prob.
#74
I ran -2.5 rear on the S, the old car. I plan to go with an initial set up of -2.5 in the rear and -2.6 in the front. In the S I ran -2.8 up front, but that had softer springs, so I'm thinking -2.6 front may be good.
The 6GT3 is bone stock. I'm going to change out the motor mounts to wevo semil solids. Install E.R.P. rear control links. Install a DAS roll bar. Install Recaro Seats and Shroth harnesses. Possibly replace some of the rubber bushings with metal. About all I have budget for this winter.
Then pray for good weather at VIR in March
#75
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i dont think you will have rubbing issues most of the time.
though stock spring may allow too much compression cause rubbing that way.
though stock spring may allow too much compression cause rubbing that way.