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Hoosier is a great company. They are sending me out two new A6's after my experience cording the two fronts in a total of 16 runs at NCAC. They examined the tires and determined that there was nothing wrong specifically with them. The problem lies in camber challenge in a stock class car and not using 50+ psi cold pressures (the 330i zhp can only get -1.3 degree of front camber at the max of its adjustment...which isn't too bad compared to some non-adjustable cars) which is fully what I expected. However, I really didn't expect cords to be showing starting around run 12.

Their recommendation now is to run very high starting pressures (52 psi up front, 45 psi rear). I had started the weekend, based on their recommendation of 38-43+ psi, at 42 psi front, 40psi rear. Noting the rollover wear up front, I upped the front cold pressure to 46psi on Sunday and the rear to 42 psi. Apparently this still wasn't enough although the rollover on Sunday was not excessive imo. I got into the groove of these tires on Sunday and did much better that day.

Left Front:




Right Front:




Left Rear:




Right Rear:





In any event, the old Dunlop SSR R-comps are looking mighty nice again. They have 30+ runs plus about 400 miles of street driving on them, and they have most of their tread left.

Not sure what path to follow. I'm considering taking the Hoosiers off and hanging on to them pending the decision of whether we mod the suspension or not. Jackie wants to learn how to install a suspension, so at least I can use that as an excuse to go with a nice setup from Ground Control or TC Kline, LOL. At least then we could get 3 degrees of negative front camber but end up in D Street Prepared I think.

The other possibility is to sell the Hoosiers...two brand new, two from the rear with 16 runs on them (rear tires were fine).

I'm curious if anyone else has experience with the Hoosier A6 on a stock class, strut suspension car that is camber challenged?

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Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

What width rim is on the 330? 1.3 degrees with a strut suspension with a nose heavy car is going to cause a lot of wear on the shoulders. It doesn't look like they were rotated front to rear (if that is possible with your setup). Were they sprayed between runs? It looks like from the tire grain that car was pushing to a high extent during some of the runs, for the rollover is extreme.

Hoosier is a great company. Hopefully these will work out better. - AB

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'14 Toyota Sequoia Platinum 4WD
Super Westerfield Bros - '93 Integra - LeChump Du Jour
STX 93 - Scion FR-S

Since it is stuck with stock class rules, it has 8" front and 8.5" rear rims hence no rotating. However, running a 245/35 on the 8" rim is less than ideal in my opinion, but the Hoosier engineer seemed to think that was ok.

I wouldn't call it too nose heavy, the weight distribution for an E46 330i with manual tranny is 50.1% front, 49.9 rear, so it really can't be more even. However, it is balanced to understeer, understeer, and the rim stagger just contributes to it. Jackie may have pushed it a bit too hard on a few corners at times, but even so I feel that this wear was a bit unexpected.

The tires were sprayed and also a thick towel soaked in water was put on the sun side front tire. It was very cool prior to the next run each time.

Hoosier said basically what I expected -- too little camber. So when I then said that perhaps these are not tires to run with a stock class car where I can't get 3 degrees of negative camber, he said I should up the pressure significantly (i.e. 52psi cold).

Here's a pic of the left side fully loaded. The front camber, although obviously not ideal by any means, does not look as bad as I thought it would:

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Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

Wow, and I thought mine were wearing fast!

245 on an 8" rim is fine. We've run them on the RX-8 all season, with the same size tire (245-35-18 ). How much more tire do you think you could fit on the front of the car?

We have 285/30/18's for the RX-8 now and they're 1.9 inches wider (tread width) than the 245's.

Granted, your car may not be able to fit them, but it certainly would help if you are on the edge of understeer. I think 52 psi cold is too high and will make the car understeer. I would go up about 8 # and go up in the rear about 12#. In a perfect world, that would make the car neutral -> slightly oversteer.

What are your alignment specs? Front/Rear camber/toe.

- AB

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'14 Toyota Sequoia Platinum 4WD
Super Westerfield Bros - '93 Integra - LeChump Du Jour
STX 93 - Scion FR-S

Our 1999 Miata can only get -1.25 max, likely a little less. I just got 70 runs out my A6s and they still have no cord showing and were sticking well at the 24 hours last weekend. I could see getting another 10 runs out of them. This included at least 24 runs on concere at the Peru Pro. Plus, Donnie's runs at the Texas Pro which may have also been concrete, but it was over 100 degrees when he ran. Regardless, they have not had an easy life and they have worn very well for us.

Eric

Bryan's RX-8 can only get -1.1 degrees negative camber up front, but like the Miata, the camber curve with a double wishbone suspension is much more friendly than with a MacPherson strut setup.

I am hoping that our new 285's can get us through the ProFinale and Tour Finale. After that, I wouldn't be upset if they corded. - AB

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'14 Toyota Sequoia Platinum 4WD
Super Westerfield Bros - '93 Integra - LeChump Du Jour
STX 93 - Scion FR-S

From what I recall, the strut to tire clearance up front is very tight right now. I doubt anything larger than a 265 would fit without different wheels/spacers/etc, but I'm not sure.



Front camber is -1.3 degrees, toe in is set at 1/32 each, total toe 1/16. I didn't want to go much further away from the toe-in spec on the front since the car is street driven 99% of the time.

Rear camber is -2.0 degrees, rear toe is right in the middle of the spec at 1/16 both sides, 2/16 total.

Chuck

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Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

I would probably adjust the rear camber a bit. In order to make the car not have the tendency to initially push, I would get rid of some of the rear camber in the car. If you can dial it back to -1.5 degrees, the rear end will want to step out a tiny bit more, but the 1/8" of toe will keep it in check. Combine that with the pressure changes I talked about earlier, and you shouldn't have any more wear problems.

GH Sharp is very knowledgable about the 330's. You might try emailing him for a little setup advice, for I know he ran Hoosiers on his 330 without killing them quickly. If I recall correctly, his email is GHSharp@aol.com - AB

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'14 Toyota Sequoia Platinum 4WD
Super Westerfield Bros - '93 Integra - LeChump Du Jour
STX 93 - Scion FR-S

We corded a brand new set of A6's at the NCAC on the front of the Celica even with 2.0 front camber which surprised the heck out of us since we had been getting much better wear than that out of other sets. I attributed it to a very abrasive surface (asphalt here is made with flint gravel which gets more abrasive as it ages) and the course designs were easy to overdrive.

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SPIN or WIN!
there's no glory for going slow.

Thanks very much for your help...sounds like a good plan!!

Cheers,
Chuck

_________________
Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

Why are you worried about the toe settings for street driving? Unless you go crazy, you could go to a little toe out in the front and it wouldn't hurt anything. Will definitely change the handling dynamic of the car, which is something to be careful of if you have non-racers driving it on the road, though. But I think you can fairly safely go to zero toe up front without endangering anyone, and it certainly won't wear your tires any worse. You could do the same in the rear, I think.

Your pressures weren't the cause of the problem, IMHO. Overdriving was. Do you have a bigger front swaybar and/or shocks on the car? If not, you were getting a lot of body roll, which pushed the car to positive camber and wore that outside shoulder like that. To cord them *that* fast I think you also *had* to be grinding those front tires through a bad push (well, *someone* was).

Sure, going to higher pressure will help, but on a strut car you really need to have a front bar. Eric's comparison with a Miata (and likely Buckley's as I think their car is also double wishbone) isn't valid as when those cars compress they do gain some camber. Strut cars don't gain hardly any as they compress (it's a camber line and not really a camber curve, as I understand it, and the line has very little slope), so if you get more than 1.1 degrees of body roll (which you likely were) then you're now at positive camber and you're all over that outside shoulder.

My STi is working the outside shoulders pretty good on 275 A6's (on the front) and that car is strut based with about the same amount of camber. We're running about the same pressures you were, and I guarantee the concrete at Wendover was harder on tires than the NCAC asphalt. But we aren't cording tires nearly as fast, and I'd have to attribute that to the big front swaybar keeping the body roll in check.


--Donnie

Yeah, I agree. I think it was the combination of pressure, over-driving them, alignment (probably should go with less toe at front, less negative camber at rear) and lack of camber.

Re BMW strut camber curve...my only recent experience is on my M5. For a while I ran the stock springs with Ground Control front adjustable camber plates, and I was only able to get -1.8 degrees at the max of the adjustment. When I changed to Dinan springs, the front ride height was lowered 7/8", and I can now get -2.3 degrees of negative camber at the max of the adjustment range. So I picked up 0.5 degrees of negative camber with a 7/8" decrease in ride height. Hence there is definitely some reasonable camber gain with compression.

I think I'm going to put the Dunlops back on the car for the rest of this year especially since Jackie will be at the Danville event alone (I'm at VIR next weekend). It will be a lot easier for her not to have to change tires at the event; however, she did do a great job changing all of them by herself while I worked the last heat at NCAC!

Chuck

_________________
Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

I also corded my A6's at the NCAC in the R. I only had 25-30 runs on them running 45 psi. I now have 2 new 710's
Bret Shillock

my experience is w/ the E36 and i'm still learning it, but our suspensions are basically the same so i'll share what i've learned.

the bigger the front bar, the better. i have a 27mm (up from 24mm stock) on full stiff up front. the stiffer i put it the better and better it bites. we NEED that front roll under control for the reasons (camber gain) above.

definately minimize your rear negative camber. My normal setup is -3 front -2 rear, and one time i dropped the rear height and the rear pushed out to about -3ish. whole different car and it pushed like crazy. and that was w/ the rear toe out gained w/ the drop! i wouldnt imagine a properly toe'd car w/ more neg rear than front. the rule of thumb for E36s is a degree less negative in rear than the front.

I run zero toe up front and the car rides very well on the highway, rough roads, etc. no tramlining so might think about that.