Bopop

Few years ago I had some bad chunking issues with a set of RS4s, I put it down to just driving on them too many laps and a bad setup. Recently I got my car back together and have done 3 trackdays at Toronto Motorsports Park over the last 2 months.
Inspecting the car I found these large chunks missing on the inside tires. I had just rotated them so I'm not sure if being on the outside had damaged the rubber and it finally let go or if there is a larger issue here. Tires have around 350 laps on them plus around 5k of street miles.





Top pic is inside front, then inside rear, then outside front. Outside rear doesn't appear to have any damage.

Car is a 2003 with 225/45/15s on 9 inch wheels. Xida XLs with 2.3 camber front, 1.8 rear, 0 toe front and 1/16 total toe in at the rear. Tire build dates are early 2019.
Tire temps are
170 160 155 LF 135 125 120 RF170 160 150 LR. 150 150 150 RR

Pressure is 31psi. The car has a k24 but it had this chunking issue even on stock power.
Is there anything glaringly bad about the setup that would cause this wear? Next alignment I'm going to see about a bit more left side camber but I believe I'm already maxed out on the left rear at the current ride height.
Or is this just something the rs4 does and I should be looking at a different Tire? I just want something that lasts and is consistent.

Thank you.

DeerHunter

Strange. My RS4s, which are used almost exclusively for HPDEs (plus driving to and from the track) don't chunk like that. I wonder if the tire was frozen at some point in its life (entirely possible if shipped during a shoulder season).

doward

I see chunking, blistering and feathering that indicates you're simply way overdriving/abusing the tires and overheating them.
The shoulder wear and tire flipping requirement is indicative of a lack of camber.

This is the age old compromise of modern 200tw street tires and dual duty alignments. Even RS4s need way more than 2.3* of camber to survive.

DeerHunter

I'll buy that. My front camber is almost -4 degrees, which makes long-distance travel, um, interesting. I killed a brand-new set of RA-1s driving to and from Laguna Seca back in 2017 (10,000 km round trip), and that was including switching them inside-out about half-way home. Wear on the track is very even though.

Bopop

On my end I store these tires inside during winter but I can imagine they get to freezing at some point in transit or storage at the local shop.

Can the RS4 even survive repeated hot laps for 20 minute sessions even with the correct setup? After about 3 laps the tire will do its best lap for me and then from about lap 5 on it gets a tiny bit greasy but will stay at that point and not lose grip for the next 20 minutes. The car is fastest with a slightly free setup on this track and I don't want to have to compromise the driving technique in order to save the tires.
I understand it will kill the tires quicker but I wasn't expecting credit card sized chunks to start coming off of them. If this use case isn't in the window of the tire would a 100tw dot slick be more in line for keeping it alive?

Based on the tire temps do you have a recommendation for a camber target? I feel like the right front is ok and was going to go for 3 in left front, and 2.5 in left rear and 2.1 in right rear.

turbofan

iTrader: (1)

I'm voting on previously frozen tires. I haven't seen that with RS4s.

Bopop

So even being frozen one before in storage will break the tire years later?

This is from the previous set I had. It's the worst one but it was ok going to the track, and then after the middle session it turned into this.

PaulF

I use RS4s on a 2ZZ Corolla in 4-hour endurance races. We run a new pair on the front for a couple of rounds and then swap them to the rear to finish them off (totally bald). I've never seen them do this.

Temps never get below freezing where that car is stored.

gesso

iTrader: (1)

Lucky Dog Racing league uses RS4s as the spec tire. We ran a 24hr race (24 hours straight) on one set of RS4's on a E46 BMW (with some flipping and rotating). Not exactly apples to apples with repeated 20 min sessions, but the tire can hold up to use.

I've had a bit of small chunking when we drove the tires really hard at willow springs in the summer (100+*), like your last picture, but nothing ever like the credit card sized bits

Bopop

I can understand the outside minor chunking due to lack of camber. But what's strange is the big chunks seem random, with half of them coming from the inside edge that isn't seeing excessive temps.
It's not a gradual chunk either, it looks like it's coming off in one massive piece.

Blkbrd69

Frozen and old = chunking.

Scaxx

Chiming in here, that's my E46 that Gesso was referring to, we were running 1* of camber in the front (stock shocks) and even then still it didn't do this. ORP is well known for eating tires, and if we were able to run camber at a more reasonable range (4+) then I have my doubts that we would have had to do more than one rotation. To Geoff's point, not exactly the same as a bunch of 20-minute sessions, but these tires definitely hold up in our experience.

We actually only ran one set of tires this year because of budget. That included 3 track day/practices (probably 1.5-2 hours of track time each), one 7 hour day in somewhat damp/cold conditions, one wet 5ish hour day, and then a mixture of 1, 2.5hr, 3.5hr, and 6hr races in one weekend. Still no signs of chunking, just (positive) camber wear from lack of camber in the front.

All this said, pretty sure your problems are due to age or where/how the tires were stored. RS4s aren't the fastest thing in the world, but they are consistent and they do last for ******* forever lol. We've corded a few pairs, but it takes actual effort to get them there.

Bopop

Sounds that while the car setup could be better, it's probably not the reason they're disintegrating. I've always sorted the tires downstairs in furnace but they had been sitting for 1.5 years while the car was being built so I'm not sure if that would negatively effect them from lack of use.

The 2 options I have now are either get a set put on immediately and try and do a last trackday of the year. Or wait till next spring and get a fresher set that hopefully hasn't been frozen.

duthehustle93

Seems like I'm beating a dead horse but I'll chime is as well. We run RS4's on an enduro NA and for a time attack prelude. The miata never has chunking issues, and the only big difference between ours and yours is we have more camber (~-3.8 front/~-2.9 rear)... these also have a 2017/2018 date code that we got second hand. The prelude does chunk a bit on the front but naturally it's FF and going to be pretty hard on front tires. The chunking is similar to your third pic in the OP but less than half as severe. In other words, another data point that this isn't a known problem on these tires and they probably weren't stored properly. Hankook has a tire tip writeup on storage, etc etc. https://cdn.shopify.com/s/files/1/05...f?v=1614373916

Bopop

Thank you.
Almost seems like the best way to buy these would be during the warmer months.
Everyone around would have to order them in and the shops out of driving distance there's no way to tell how they're stored.
I'll be moving up to a 245 for next year and thinking maybe ordering them from a distributor in the US would be a bit safer.