ZOIKS! A048s shot in under 700 miles!?

[codymac]

I don't know whether to be proud or embarrassed. As I've told everyone around me... it's not that I'm going fast, it's just that I'm not slowing down for the corners.


I guess I've been a little too enthusiastic about making up for engine break-in by enjoying the turns. Good thing I live in a place where the roads are all flat and straight.

Is this the type of mileage I should expect from the A048s? 669 miles to shagville?

[charliex]

the tires look like they are overinflated , centre worn, (normally delivered overinflated for shipping to stop flat spots) and get your alignment checked. needs more negative camber too.

[fishguy]

agree they are way overinflated, if you are running like that you are only getting about 1/3 of the contact patch of the available amount of the tire to the road surface (poor traction). your cornering will be more grip if correct inflation. these tires are race tires, and 700 miles on a track is allot of laps.......... if you are driving hard on them in corners, expect them to wear fast. if you want to play, your gonna pay. i would think they should wear much longer than what your getting though. how hard are you hitting those corners?

[goelise]

ok, so for street use what should one inflate the A048s to? Any difference between front and rears?

[Dro]

The spec is printed on a label in your door sill. 26 front, 29 rear, cold.

[codymac]

Originally Posted by fishguyAZ

how hard are you hitting those corners?

I claim ignorance!

My speedo is stuck at 20mph. I seem to recall 4500rpm being 80-ish indicated in 6th on the trip back though. For reference, I wasn't kidding when I mentioned an R1 being in the way on some twisty backroads.


I just went out and checked:
LF = 27.5 psi
RF = 27.5 psi
LR = 28.0 psi
RR = 27.5 psi

Surely a pound or two isn't going to make that much of a difference. (Rationalizing follows) If it really does, I can see it being much more economical to pick up another set of wheels and run harder tires on the street - of course, that kinda takes the fun out of everything. Like being married to a supermodel you can't touch.


Definitely need to see about getting the alignment checked too... and finding helium filled shoes... and buying stock in Yokohama.

[charliex]

you could fit streets like the goodyear F1s but by the looks of your progress so far, you might need the grip of the yokies

i'd think even a 1lb would make a big difference its a lot of volume and then they heat up, which seems to be apparent from your tyes.

be interesting on your first service when they have to do an ecu dump and replace the tyres

[codymac]

Originally Posted by charliex

be interesting on your first service when they have to do an ecu dump and replace the tyres

GULP!


Honestly - I've been a good boy.

[zvezdah1]

Perhaps your tire gauge is inaccurate, I thought most people were getting around 3-4k miles on a048s.

Chris
silently saying to himself "thank god I got standard suspension and 07s!!!" as I'm already at 2500 miles in first month.

[fishguy]

Originally Posted by codymac

GULP!


Honestly - I've been a good boy.

too funny codymac lmao!!!!. I was amazed at how even 1 lb makes a difference at the HPDE i did. i made it to be approved for level four on my first day out, i do have expereince with racing on two wheels, but the tires and the pressures being so , so , so critical was new for me, i guess i never pushed my bikes that hard on the track(pity, but probobly smart)......... my cold psi of 28 went to 36 when hot, it sounds like your tires are definatley getting "warm". i had too much psi for most of one day @HPDE, and my tires wore similar to yours, but i was checking them every session, and compensating. a long run w/o checking them would surely wear like yours show. i dont have much experience with these but i am trying to share what i had to learn fast, but i guess....................where is this R1???? it sounds like ..............fun. get a white grease pencil(for alignment @ autoparts store) and mark on your tires near the edges but on the contact patch area, see what wears off. this is what i am going to do next time out.

[codymac]

I actually measured it with two gauges to confirm - my trusty old analog and a newfangled digital. Pretty sure my measuring is OK, (I got my technique down and everything, I don't be ticklin' or nuthin'.)


Good point on the white grease pencil - I'm thinking a pyrometer would be a wise investment for the track.

The R1 was some guy on 2222 in Austin - I have to admit that he was working pretty hard to compensate for not using all the lean angle available to him. But hey, he was riding his pace and having good fun. Before getting in front of me he failed to realize that I was doing the same...
only faster.

[NOB]

With all the talk of how quickly the oa48's wear out I have to say I was worried that as agressive of a driveras I am I wouldn't even get 3k out of them.Well Im at 4400mi in a month and a half well mabye two months and my tires are doing very well I dont believe im even at the half way point of their wear. Now that I think of it I have put about 2200mi on the highway.Hopr they last a little longer!

[Maxster]

Cody,
I drive the Storm Titanium Exige that was parked next to yours yesterday. I am intrigued about your wear rate. The tire presure may be a contributing factor but hardly the culprit. Visually, your car appeared to have significant negative rear camber (although without proper measurement this may be just a perception problem) but did not look apreciably lower nor higher than mine.
If I were you, probably would check the alignment for starters. Also, have you considered corner balancing just a precaution.
Do you have Traction Control? My Exige has 450 Miles so far and the wear is far brom being half of yours but I do have Traction Control (no LSD).
Lastly, we discussed this briefly but again, the OEM tires are supposed to be Medium Hard and there are softer compounds that look identical, the LTS designation is an indication that you have the right stuff.
I will not be in town this weekend but let me know when do you want to take your car to the track and I believe that the local Porsche chapter rented MSR for the weekend including Monday.

[codymac]

Thanks, Maxster. Nice to meet you and your wife yesterday! It's great having you around to compare notes with.


I definitely plan on hitting you up for an MSR invite once I've gotten her sorted and the first service over with. I started calling around this morning to see about alignments and have a few more calls to make before I decide which shop to take her to. I want to get her corner balanced as well - figured I might as well do it all at once.

I suspect fishguyAZ pointed out a good part of it: tire pressure increases at temp. may have been a large contributing factor. We'll know for sure once I get her on a rack.

In the meantime - be sure to keep an eye on those *hot* pressures too.

[fishguy]

cody, my track day i went up witha really nice accurate tire psi guage. it showed up to 60 psi longacre type, but got it on ebay differnt brand and it worked great. i am going to purchase another one that only goes up to 30 psi, so i can get very accurate 1/2 LB readings as well. this was good, but the guy next to me, an nice older guy who had been racing his car for years said"you need a pyrometer", "and the grease pencil". he was super cool. he broke out with a digital pyrometer, showed me how to use it, and said what really works better is this................ and showed me the probe type pyrometer. that he didnt lend me, as he used it, no longer the digital one. i am going to definatly get the probe pyrometer asap, AND the grease pencil, AND the 30 psi tire guage. traction is everything for the track day, and this arsenal of tools will do all that is needed.That is i i know how to use these tool correctly......................expensive tires, so i hope the learning curve is steep. i saw some nice stuff on ebay. good luck btw I was shocked at how much the psi went up from cold to hot. guy next to me said you want about no more than 10% change from the two, although I am sure that depends on tire makes etc........... still so much to learn.

[zvezdah1]

Can someone recommend a good accurate tire pressure gauge? Had mine compared with a race teams gauges and it was 4 psi off.
Chris

[John Stimson]

According to Consumer Reports the digital gauges were the most accurate and reliable. The mechanical dial gauges can go off pretty easily if they get banged around or dropped. I think the one they recommended was Accu-Tire or something like that, from Radio Shack. That was a couple years ago.

You can get a digital Longacre racing gauge that's accurate to 1/2 psi for about $35, or you can get 5 times the precision for 5 time the price... www.longacreracing.com

[zvezdah1]

Thks very much John, sounds like the longacre will serve my purpose!
Chris

[Elise 323]

Definitely have the alignment checked at a competent shop. My Elise had 1/4 inch of front toe-in and double the specified toe-in at the rear. Tire wear was measurable at 500 miles. Another Elise had toe out in the rear creating too much oversteer. Pulling the front camber shims and ABS bracket made a very nice improvement in front grip. Toe at zero in the front and 1.2 mm/each at the rear is working well with Toyo Proxes T1Rs.

Easy to calculate the rise in tire pressure with increasing tire temperature. It is not much on the street but can be significant at the track. If your tires are very warm to the touch on the street, at a reasonable ambient temperature, they are most likely scrubbing due to suspension misalignment. A dry gas in the tire eliminates steam formation and dramatic pressure increase if the tire approaches an undesirable 212F. A pound or two in cold tire pressure will not materially affect wear on a descently constructed tire.

Too bad Lotus is so weird on this topic but a vigorous break-in during the first few (0-50) miles really decreases oil consumption and produces more power. Sealing the rings is so important. That is the reason the factory oil fill is not synthetic.

[fishguy]

Originally Posted by zvezdah1

Can someone recommend a good accurate tire pressure gauge? Had mine compared with a race teams gauges and it was 4 psi off.
Chris

I got this on ebay, great product, great seller. he has 30 psi max ones i want also. i was impressed with this item thoroughly
http://cgi.ebay.com/ebaymotors/ws/eB...Pr4_PcY_BIN_IT