XXR 527_ Good or bad wheels for autocross

[RAYSSPL]

They'll do just fine in autox since it's mainly low speed. But I wouldn't use any wheel by XXR on a high speed track.

The reason why these wheels are heavy is because they're gravity cast wheels which is also the weakest way to manufacture a wheel. So that's a double negative right there.

[random hero]

Originally Posted by celica73

Exactly, and when you lose by 0.05 to someone you will want to spend money to make up that difference. Sure, you could have driven better, but the 15 lb wheels would have gotten you there vs the 20 lb wheels.

Let's see, $250 each for 15.5 lbs, or $150 each for 19 lbs. Difference? $400. At resale, you should be able to get $200 of that difference back.

ONE set of good autocross tires >$600 and that is a wear item, residual value is Zero. In the long run, the better wheels cost about $200 more. Actually, after you buy the heavy wheels and start to care and then buy the light wheels, the heavy ones cost you an extra $600.

you think lighter wheels will drop your lap times that significantly ..... Any data to back that up?

[celica73]

Originally Posted by random hero

you think lighter wheels will drop your lap times that significantly ..... Any data to back that up?

You do realize that 0.05 seconds on a 60 second autocross course is about 5 feet. Yes, I do believe cutting 20 lbs of rotating mass will make that difference. 20 lbs of driver will make that difference.

The question is, why don't you believe 0.05 seconds can be made up by 20 lbs.

[random hero]

I thought I read .5 seconds... my bad

[mkiisupra]

I use a set of 15 inch xxr002's for autox, they've only had Dot-R/UHP tires, road also. They've been good wheels for me, and unless you autox with a huge, evenly-driven field of identical cars, the time differences caused by different diameters/width in rims, and driver mass will be made up with driver education, effort, and eventual skill. So buy the wheels you want and understand that, yes, any diameter larger than 17 will slow you down.

Eric G

[BBSU]

The XXR 527's are replicas of the Wedssport tc105n. The tc10n's are only 15.4lbs! but they cost a lot more then the XXR's that's for sure. Long term id try to spend the extra money for the Wedssports

[dori.]

Originally Posted by BBSU

The XXR 527's are replicas of the Wedssport tc105n. The tc10n's are only 15.4lbs! but they cost a lot more then the XXR's that's for sure. Long term id try to spend the extra money for the Wedssports

no, they are not. there are noticeable differences between them.

we're not talking grids vs te37's here. close but not the same.

[diirk]

Originally Posted by celica73

You do realize that 0.05 seconds on a 60 second autocross course is about 5 feet. Yes, I do believe cutting 20 lbs of rotating mass will make that difference. 20 lbs of driver will make that difference.

The question is, why don't you believe 0.05 seconds can be made up by 20 lbs.

My understanding was that rotating/unsprung weight was equal to about 3x static mass. IE: shaving 20lbs of rotating mass is equal to shaving about 60lbs of static mass. In addition to allowing a person to more accurately tune their suspension.

[BBSU]

Originally Posted by dori.

no, they are not. there are noticeable differences between them.

we're not talking grids vs te37's here. close but not the same.

ouuu. oops.

[stockysnail]

Originally Posted by jstn

Do not run 18's in autocross. You will easily lose at least a half second on a 60 second course. People on this forum slap 18's on it all the time because it looks nice, but the fact is that the FR-S is demonstrably slower with 18" wheels. If you really just want to fill in the fender gap, lower the car. Down the road if you mod the car and add a lot more torque, sure put 18's on it then if you still want to.

Autocross = little wheels, lots of tire, doesn't matter what it looks like.

Some 16x8 et25 Enkei Compe with 245/45R16 with some RE-11 or R compound should be even better than 17" wheels then. I've been going back and forth between that and 17x8 running 245/40R17. Supposedly the 16x8 with 245 is the ideal width but 245 on 17x8 is just .5" more tire than ideal. Both are about as close to stock geometry as you can get. Speedo should be accurate and no loss because of taller overall tires/wheels.

[stockysnail]

Originally Posted by random hero

you think lighter wheels will drop your lap times that significantly ..... Any data to back that up?

I read an article, that I don't have the link to, that tested Mazda Miata's with identical tires with identical sized wheels with the only difference being the weight (I think it was about 5lbs difference between the two). Times around the track showed that it didn't matter the weight of the wheel. There were laps where the heavier wheel was faster and some where the light ones were. All were very close however. I learned after reading the article that wheels weight doesn't matter. It's all about the drive. Tire compound and tire width does however matter.

[was385]

Originally Posted by karma003

As the title says. Sorry didn't know what subject it should be in, but figured since it was more directed to the autocrossing group, id post here. I love the xxr527's but I was curious how they r performance wise. What r the pros & cons of it. Plz explain w as much detail as possible plz. Thank you

As some others have said, it's all about your priorities. If you want to fight for every hundreth of a second and be competitive, I wouldn't suggest 18s and I wouldn't suggest XXRs. If you just want to go out and have fun and your bigger priority is aesthetics, then buy these. They're certainly safe for autox every once in a while. Just comes down to your goals for the car.

[CatDaddysBBQ]

Originally Posted by celica73

You do realize that 0.05 seconds on a 60 second autocross course is about 5 feet. Yes, I do believe cutting 20 lbs of rotating mass will make that difference. 20 lbs of driver will make that difference.

The question is, why don't you believe 0.05 seconds can be made up by 20 lbs.

Anybody that has ever swapped out wheels and lost a few lbs in each corner knows the benefits. It may/may not line up to a stopwatch, but faster turning, more feel and better braking is just better when autoXing.

[jflogerzi]

Look at Rota Titans. Pretty damn light and still cheap. Good quality. Just not JP quality...