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Setup Help - Tires with new wing

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Old 04-23-2012, 12:05 PM
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himself
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Default Setup Help - Tires with new wing

Gurus,

I put on a big wing (Aeromotions, 65" wing) on my 996 GT3. Alignment in the rear is set at -2.4 camber and .13' toe-in. Car is running 700/900 springs. Pressures are targeting at 36-38 hot. I didn't get pyrometer readings.

I am now consistently cording inside edges of rear tires. I had a set of Eagle RS tires that died (to the cords on the inside edge) and then put on a scrub set of R6s that also corded on the insided edge. This is happening on both sides simultaneously, although the loaded tire shows a bit more wear.

Question: do I need to take some camber out with the wing now? Adjust toe? Reduce springs? Change something else?

I dig the new wing, but it's a pretty pricey experiment changing one variable and then running through a set of rears. I figured I'd ask those in the know and save some time and heartache.

Thanks!

-td
Old 04-23-2012, 01:06 PM
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Scootin159
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It does sound like you're working the outside of the tires too much, but getting a pyrometer would be a much more cost effective way to diagnose tire usage than looking at what part of the tire is wearing out first. I suspect you'll find that the inside edge of the tire is significantly hotter than the outside - you'll want to reduce camber until you get the temps more even across the tire.
Old 04-23-2012, 03:39 PM
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analogmike
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You SHOULD cord the inside edge before the outsides if your car is set up right. if you have well under half tread in the middle, I would leave it.
Old 04-23-2012, 03:48 PM
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Veloce Raptor
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Agree with Mike...however, if tire life is essential, take a bit of rear camber out.

Also, don't forget with all that wing you will need to adjust front splitter to balance the car.
Old 04-23-2012, 05:00 PM
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007DT
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Here is my Set-Up.
Mainly run Nitto NT01

Alignment
Front
Camber - 3.2
Toe .2mm (OUT)

Rear
Camber - 2.8
Toe -2.5mm (IN)

Sways
Front 1 off full stiff
Rear 1 off full stiff

Moton Clubsports 14 way
Front - Spring Rate 685#
Rear - Spring Rate 913#

Also have RS Wing and Cup Splitter
Old 04-23-2012, 05:49 PM
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himself
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This isn't an issue of cording the inside edge first. It's cording the edge after 2 sessions. I ran through 6 rears in 1 weekend - all corded on the inside edge. None of these were sticker tires.

-td
Old 04-23-2012, 06:46 PM
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spare tire
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It could be that your rear toe is out of alignment. It might be a combination of camber and toe. If you floor it hard to induce wheelspin (like a dragster) you could be the source of your problem. Cording a new tire in 2 sessions is not normal. 315 wide MPS cups also used to do this because they are too wide for our stock wheels. 315 Hoosiers or other tires were not a problem. What brand, model and hot pressures are you running?
Old 04-23-2012, 06:47 PM
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Veloce Raptor
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Yup, TD have your toe verified...
Old 04-23-2012, 08:16 PM
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utkinpol
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Originally Posted by himself
This isn't an issue of cording the inside edge first. It's cording the edge after 2 sessions. I ran through 6 rears in 1 weekend - all corded on the inside edge. None of these were sticker tires.

-td
if you have stock toe arms in rear it is common for them to move under pressure, that`s why people get tarett arms.
http://www.tarett.com/items/996-997-...lnk-detail.htm

if you already have `em just re-check the toe settings.
Old 04-23-2012, 09:15 PM
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bobt993
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Td, is your toe per side or total?
Old 04-23-2012, 09:31 PM
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himself
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I ran a set of hooter 295s, eagle rs 315 and hooter 315. All corded inside edge rapidly. Although first set lasted 5 sessions.

Toe is .13' per side. I have tarret toe atms with locking plates. Will have aligent verified ASAP.


-td
Old 04-24-2012, 11:48 AM
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spare tire
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You are not on a banked track are you? Daytona? Roval?
Old 04-24-2012, 03:02 PM
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autometrics
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Inside wheel spin due to a weak diff?
Old 04-24-2012, 10:01 PM
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JackOlsen
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I've been surprised before... but I would be very surprised if any kind of wing could produce a sudden and noticeable change in tire wear on a production-based car. Unless you're running for long, long stretches at 160 mph, the effect on the tires is probably comparable to driving with a passenger's additional weight or running a few extra laps per session.

I suspect your alignment settings have changed. Toe the most likely.
Old 04-25-2012, 11:41 AM
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onefastviking
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Originally Posted by himself
Gurus,

I put on a big wing (Aeromotions, 65" wing) on my 996 GT3. Alignment in the rear is set at -2.4 camber and .13' toe-in. Car is running 700/900 springs. Pressures are targeting at 36-38 hot. I didn't get pyrometer readings.

I am now consistently cording inside edges of rear tires. I had a set of Eagle RS tires that died (to the cords on the inside edge) and then put on a scrub set of R6s that also corded on the insided edge. This is happening on both sides simultaneously, although the loaded tire shows a bit more wear.

Question: do I need to take some camber out with the wing now? Adjust toe? Reduce springs? Change something else?

I dig the new wing, but it's a pretty pricey experiment changing one variable and then running through a set of rears. I figured I'd ask those in the know and save some time and heartache.

Thanks!

-td

Will you be out at TWS this weekend for NASA or next for PCA ?
If so come find me and we can discuss this.


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