Interesting Tire Tread Wear Pattern
#1
Rennlist Member
Thread Starter
Interesting Tire Tread Wear Pattern
After 8 days of tracking my Goodyear Eagle F1 Asymmetric's have developed an interesting wear pattern.
On the front tires, the outer tread blocks are nearly flat on one side (trailing edge) and have a lip on the other side (leading edge). Also, the center tread block between the two rain grooves is nearly flat on the outside edge but fairly tall on the inside edge. Side wear marks on the outer edges of the tires come down to the tip of marker arrows and not down to the base of the arrow.
On the rear tires, essentially the same pattern.
Front camber is -0.45' and -0.49'
Front toe is 0.03' and 0.03'
Rear camber is -1.55' and -1.54'
Rear toe is 0.07' and 0.07'
Tires still feel pretty good on the track. Been running tire pressures around 37.5-38.5 hot and consistently taking Pyrometer readings which are just about even (inside, middle, outside).
Is this typical if you run street tires and don't shave the tires?
Any other thoughts?
Thanks.
On the front tires, the outer tread blocks are nearly flat on one side (trailing edge) and have a lip on the other side (leading edge). Also, the center tread block between the two rain grooves is nearly flat on the outside edge but fairly tall on the inside edge. Side wear marks on the outer edges of the tires come down to the tip of marker arrows and not down to the base of the arrow.
On the rear tires, essentially the same pattern.
Front camber is -0.45' and -0.49'
Front toe is 0.03' and 0.03'
Rear camber is -1.55' and -1.54'
Rear toe is 0.07' and 0.07'
Tires still feel pretty good on the track. Been running tire pressures around 37.5-38.5 hot and consistently taking Pyrometer readings which are just about even (inside, middle, outside).
Is this typical if you run street tires and don't shave the tires?
Any other thoughts?
Thanks.
#4
Nordschleife Master
I can't say yet. I can tell you more after my track day on March 17th. Turn in seems crisper, but who knows if it's just a placebo effect or if it's because of the new alignment. I'm running -2.0 camber in the front and -1.8 camber in the rear.
#5
Three Wheelin'
In my experience, solid/free moving bearings work better on rapid impacts like expansion joints or quick undulations (almost feels like you've lost some unsprung weight), but you lose a little 'stiffness' from the suspension which is more noticeable on higher speed stuff.
Thanks, I trying to decide if I want to do this before I get my car back from SharkWerks.
#6
Nordschleife Master
Steve, I can't say for sure yet. I haven't driven the car much since the LCAs were installed. I can get you more feedback hopefully next week after my thunderhill track day... that is, if it doesn't rain on me.... (I can't believe it's supposed to rain the one weekend I need it not to rain this whole dry season....)
#7
The stock car just doesn't allow enough camber for track use. The LCA with camber plates should allow you to set the ride height (probably a little lower) and get the neg camber needed. Around -3 and 2.75 for the rear is considered a conservative alignment for track use on most cars. You would also be tweaking the toe and caster. You may benefit from talking to the spec boxster racers for specs. Good luck.
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#8
Burning Brakes
Steve, I can't say for sure yet. I haven't driven the car much since the LCAs were installed. I can get you more feedback hopefully next week after my thunderhill track day... that is, if it doesn't rain on me.... (I can't believe it's supposed to rain the one weekend I need it not to rain this whole dry season....)
#9
Nordschleife Master
You sound like David Ray
I've done a track day in the rain before. Good for the experience, but if I'm going to drive 2 hours there and back, I'd much rather it be in sunny weather. Still hoping for the best... Sunday might be the better day...
I've done a track day in the rain before. Good for the experience, but if I'm going to drive 2 hours there and back, I'd much rather it be in sunny weather. Still hoping for the best... Sunday might be the better day...
#10
Nordschleife Master
Steve, I ended up bringing the spyder to the track this past Sunday. I can tell you with the new alignment that the car does not understeer anymore, which is very nice. I haven't noticed a difference in the effective spring rate with the LCAs, but to be honest I'm not sure my skills are honed enough to notice those types of things, especially since the last time my spyder was at the track was about a year ago.
#11
Rennlist Member
Thread Starter
Tread pattern issue resolved. I think I can safely say that the higher hot tire pressures 36.5 front and 38 rear and less aggressive alignment caused this. I did a lot of experimenting with different track pressures. The last 3 days of tracking I lowered the hot tire pressures to 30 front and 31 rear and all the uneven tread blocks completely wore off. So a little bit of good news and bad news. The good news - the lower pressures increased the contact patch which was intentional because it did rain off and on and a few of the sessions were on a wet track. The bad news - the lower tire pressures caused the tires to wear very quickly (after holding up quite well for 13 track days and 5500 miles) and now the fronts have cords showing. In the shop tomorrow for a more aggressive alignment and a new set of Sport Cups!
#12
Three Wheelin'
Steve, I ended up bringing the spyder to the track this past Sunday. I can tell you with the new alignment that the car does not understeer anymore, which is very nice. I haven't noticed a difference in the effective spring rate with the LCAs, but to be honest I'm not sure my skills are honed enough to notice those types of things, especially since the last time my spyder was at the track was about a year ago.
I notice the spring effect most on the highway... high speed undulations (60-ish mph on 2-lanes and higher on some freeways).
LCAs go on my wife's 2000 Boxster S on Friday. If the don't bother me on her car (and with your positive report), it sounds like I may have to go for the LCAs on the R, too. MPSCs are already on their way. Anyone need a set of 5,000 mile PS2s in Spyder/R sizes, cheap?
#13
Three Wheelin'
Tread pattern issue resolved. I think I can safely say that the higher hot tire pressures 36.5 front and 38 rear and less aggressive alignment caused this. I did a lot of experimenting with different track pressures. The last 3 days of tracking I lowered the hot tire pressures to 30 front and 31 rear and all the uneven tread blocks completely wore off. So a little bit of good news and bad news. The good news - the lower pressures increased the contact patch which was intentional because it did rain off and on and a few of the sessions were on a wet track. The bad news - the lower tire pressures caused the tires to wear very quickly (after holding up quite well for 13 track days and 5500 miles) and now the fronts have cords showing. In the shop tomorrow for a more aggressive alignment and a new set of Sport Cups!
#14
Nordschleife Master
Thanks for the update, Joe. So tire trashing is no longer an issue? What alignment settings did you go with? How was the car in the rain?
I notice the spring effect most on the highway... high speed undulations (60-ish mph on 2-lanes and higher on some freeways).
LCAs go on my wife's 2000 Boxster S on Friday. If the don't bother me on her car (and with your positive report), it sounds like I may have to go for the LCAs on the R, too. MPSCs are already on their way. Anyone need a set of 5,000 mile PS2s in Spyder/R sizes, cheap?
I notice the spring effect most on the highway... high speed undulations (60-ish mph on 2-lanes and higher on some freeways).
LCAs go on my wife's 2000 Boxster S on Friday. If the don't bother me on her car (and with your positive report), it sounds like I may have to go for the LCAs on the R, too. MPSCs are already on their way. Anyone need a set of 5,000 mile PS2s in Spyder/R sizes, cheap?
We lucked out and didn't get any rain. Only 2 minutes of hail, and then quickly dried out afterwards. Very strange weather day, but I pretty much ran on a dry track.
How much tread wear on the ps2s? even wear?
#15
Three Wheelin'
Tires are already trashed. I'm hoping my next set won't wear as quickly as my first set did. I'm running -2.0 camber in the front, and -1.8 in the rear. Some guys are going even more aggressive than that because even with -2.0 they are still getting some increased outer edge wear.
We lucked out and didn't get any rain. Only 2 minutes of hail, and then quickly dried out afterwards. Very strange weather day, but I pretty much ran on a dry track.
How much tread wear on the ps2s? even wear?
We lucked out and didn't get any rain. Only 2 minutes of hail, and then quickly dried out afterwards. Very strange weather day, but I pretty much ran on a dry track.
How much tread wear on the ps2s? even wear?
And thanks for the alignment numbers. It's good to have as many data points as I can get.
There's not a lot of wear on them, and they were completely even... at least when I dropped it off with Alex.
The Tubi exhaust is supposed to be back from coating sometime this week. I'll let you know once it's installed. If you still plan on dropping by Sharkwerks to hear it, you can look at the tires, too.
I'm easy; just glad that I'm finally getting resolution on all the stupid things that have taken the fun out of the car.