Track forum general chit chat.

[dparm]

Originally Posted by bigjae1976

My development of plywood aero parts continues. Plywood > Carbon Fiber :

The Audi R8 LMS cars use wood (I think balsa) in the front splitter. They said it's because the wood is strong and light, and it keeps replacement costs low for the teams since those splitters are typically destroyed by the end of each race.

Originally Posted by macdude357

I'm surprised no one has mentioned the new Dunlop ZIII. They have a 275/35/18 and performance is probably pretty close to the RS3.

ZIII isn't really new. It's a toned-down Star Spec, IIRC. Been out for a few years.

[CorruptCommie]

Originally Posted by dparm

The Audi R8 LMS cars use wood (I think balsa) in the front splitter. They said it's because the wood is strong and light, and it keeps replacement costs low for the teams since those splitters are typically destroyed by the end of each race.

It's an Audi, it's made out of non-conductive materials to minimize electrical problems.

[Visceral]

Originally Posted by CorruptCommie

It's an Audi, it's made out of non-conductive materials to minimize electrical problems.

Its all Bosch, but the Audi electronics do seem magically even less reliable than BMW... almost on par with Volvo and something made with Lucas.

[kyippee]

Interesting 2 comments about Toyo RR vs NT01 earlier... my friend running his ND2 Miata on both NT01 and RR said that RR do give feedback and squeal. But they don't really get slip angle easily, so harder to get the car rotated.

I'll hold off for now, probably run a few more sets of NT01

[slicer]

Originally Posted by StripclubDJ

I thought TD was discontinued Awhile ago?

I thought so too but they are on Discount Tires's site. I called Hankook and they told me that they were still in production about a month ago.

[gmx]

Yeah they are popular here along with A050s.
Most M3s use medium or the hard compound. The soft seems to heavy for a street car especially hotter days.

[PrimeBMW]

Originally Posted by kayha12

Currently running the RRs (2 weekends worth of tracking) however no experience with NT01 or TDs. What I do like and appreciate about the RRs (at least so far) is that they are pretty talkative for being a "slick"

Personally I don't want a tire to make any premature noises. NT01? No thank you. Or any tire that "talks" for that matter. I prefer to feel it.

[M3 Number 86]

Originally Posted by macdude357

I'm surprised no one has mentioned the new Dunlop ZIII. They have a 275/35/18 and performance is probably pretty close to the RS3.

Tito lost philomanilo challenge because of those tires lol

He said they're garbage.

[dparm]

kpewpew how the hell did you bend a set of forged wheels? Are those Titans not as strong as they like to claim?

[kyippee]

Originally Posted by dparm

kpewpew how the hell did you bend a set of forged wheels? Are those Titans not as strong as they like to claim?

I don't know, they just bent. They took care of me and replaced my set.

[dparm]

Originally Posted by kpewpew

I don't know, they just bent. They took care of me and replaced my set.

What was the extent of the damage? How did you know they were bent? Did you have any particularly bad "offs"?

Does Titan 7 provide load ratings for their wheels? When I was researching forged wheels to make sure I could get a set that could handle track use, I found that very few companies actually gave you this information. Forgeline rates theirs depending on the type of tire you run, for example.

Great to hear they upheld the warranty and didn't weasel out of it. Too many companies claim to make track-ready products but will quickly disavow coverage if they think you actually used it on the track.

[kyippee]

Originally Posted by dparm

What was the extent of the damage? How did you know they were bent? Did you have any particularly bad "offs"?

Does Titan 7 provide load ratings for their wheels? When I was researching forged wheels to make sure I could get a set that could handle track use, I found that very few companies actually gave you this information. Forgeline rates theirs depending on the type of tire you run, for example.

Great to hear they upheld the warranty and didn't weasel out of it. Too many companies claim to make track-ready products but will quickly disavow coverage if they think you actually used it on the track.

I felt the vibration at >=70mph and it was shaking quite a lot. Got the wheels inspected and got a quote to repair bends. They were clearly bent, although "minor" bends. The E92 M3 platform is sensitive to bends.

Don't recall load ratings... I've gone with disposable wheels for now and have already replaced my initial set of EC7 using the Apex warranty. Disposable wheels on street too, SM10 which I feel have very minor bends.

I don't think any wheel is invincible. Might swap to BBS RIA for street just because of knowing how solid BBS wheels are and my past experiences. Track, I may stick with disposable. I don't really feel the vibrations of minor bends when I'm driving on track lol.

Oh and no specific offs with the Titan 7 wheels. I think they bent on street. I was driving slow back then..

[dparm]

Originally Posted by kpewpew

I felt the vibration at >=70mph and it was shaking quite a lot. Got the wheels inspected and got a quote to repair bends. They were clearly bent, although "minor" bends. The E92 M3 platform is sensitive to bends.

Don't recall load ratings... I've gone with disposable wheels for now and have already replaced my initial set of EC7 using the Apex warranty. Disposable wheels on street too, SM10 which I feel have very minor bends.

I don't think any wheel is invincible. Might swap to BBS RIA for street just because of knowing how solid BBS wheels are and my past experiences. Track, I may stick with disposable. I don't really feel the vibrations of minor bends when I'm driving on track lol.

Oh and no specific offs with the Titan 7 wheels. I think they bent on street. I was driving slow back then..

Why do you say the E92 platform is susceptible to bends?

I would really tell you to take a look at Forgeline if you're already willing to spend the cash on BBS. Much like BBS, they are making legitimate race car wheels. Look in the IMSA paddocks: everyone is running BBS or Forgeline. My experience with them has been absolutely stellar both in customer service, product quality, and post-sales service.

[BayE30]

sensitive to bends, not susceptible.

as in you feel everything in the steering wheel, which is very true.

Originally Posted by dparm

Why do you say the E92 platform is susceptible to bends?

I would really tell you to take a look at Forgeline if you're already willing to spend the cash on BBS. Much like BBS, they are making legitimate race car wheels. Look in the IMSA paddocks: everyone is running BBS or Forgeline. My experience with them has been absolutely stellar both in customer service, product quality, and post-sales service.

[slicer]

Originally Posted by kpewpew

I felt the vibration at >=70mph and it was shaking quite a lot. Got the wheels inspected and got a quote to repair bends. They were clearly bent, although "minor" bends. The E92 M3 platform is sensitive to bends.

Don't recall load ratings... I've gone with disposable wheels for now and have already replaced my initial set of EC7 using the Apex warranty. Disposable wheels on street too, SM10 which I feel have very minor bends.

I don't think any wheel is invincible. Might swap to BBS RIA for street just because of knowing how solid BBS wheels are and my past experiences. Track, I may stick with disposable. I don't really feel the vibrations of minor bends when I'm driving on track lol.

Oh and no specific offs with the Titan 7 wheels. I think they bent on street. I was driving slow back then..

Originally Posted by dparm

Why do you say the E92 platform is susceptible to bends?

I would really tell you to take a look at Forgeline if you're already willing to spend the cash on BBS. Much like BBS, they are making legitimate race car wheels. Look in the IMSA paddocks: everyone is running BBS or Forgeline. My experience with them has been absolutely stellar both in customer service, product quality, and post-sales service.

As you both know, not all wheels are created equal. Just because a company says their wheels are 'forged' it doesn't equal indestructible. Some companies simply build better products, have more experience, do more testing, etc. BBS is obviously hard to beat when you consider the amount of true, high level, race testing they have performed for decades. Forgeline is my favorite US boutique wheel manufacturer at the moment. I agree, they are legit. That being said, I don't think Forgeline is offering anything at the quality of the Forged RIA at the RIA price point. That wheel is such a great bang for the buck. However even the best wheels can bend too. Not trying to claim they are indestructible

[dparm]

So is anyone going to be at COTA this weekend with NASA Texas?

[macdude357]

Originally Posted by dparm

kpewpew how the hell did you bend a set of forged wheels? Are those Titans not as strong as they like to claim?

I was washing my Titans the other day and noticed the load rating stamped into the barrel. 590kg which is around 1300lbs. Not sure how load rating plays a part but even APEX ARC 8's have a higher load rating than that.

[dparm]

Originally Posted by macdude357

I was washing my Titans the other day and noticed the load rating stamped into the barrel. 590kg which is around 1300lbs. Not sure how load rating plays a part but even APEX ARC 8's have a higher load rating than that.

That's a big yikes from me. And they don't even tell you what tire that's on. For comparison, my Forgeline GS1Rs are rated at 2100 pounds on street tires, 1300 on R-comps, and 1100 on actual race tires.

Load rating is a big deal. It all comes down to fatigue cycles and the amount of lateral acceleration your car can pull. Think about the stress the wheel is under when you're doing 1.4g in your 3200 pound car. And how many times per session is each wheel seeing that stress?

If you investigate fatigue failures of metals like aluminum, if you never load the material more than 50% of the yield point of the material then it will have an infinite life (infinite stress cycles). The closer the load on the wheels comes to the yield point of the material, the less cycles it can handle before it breaks. Fatigue strength is a logarithmic curve, so as you approach the yield point, even small changes have a disproportionately bigger effect. The moral of the story, identify WORST-case loads on the wheels and then design so that no part of the wheel EVER goes past the 50% point. A good FEA will identify that and it's why I don't buy the "wheels are consumables" bullshit.

[kyippee]

Oh fook I'm learning. My EC7 have a 1550lb rating and I bend them easily on track.

I read bimmerworld TE:AL have a higher rating.. found this [correction: 690kg stamping which is 1521lb]

Source: http://www.m3forum.net/m3forum/showthread.php?t=575718
And some technical/production details http://www.m3forum.net/m3forum/showp...0&postcount=23

[slicer]

Originally Posted by dparm

That's a big yikes from me. And they don't even tell you what tire that's on. For comparison, my Forgeline GS1Rs are rated at 2100 pounds on street tires, 1300 on R-comps, and 1100 on actual race tires.

Load rating is a big deal. It all comes down to fatigue cycles and the amount of lateral acceleration your car can pull. Think about the stress the wheel is under when you're doing 1.4g in your 3200 pound car. And how many times per session is each wheel seeing that stress?

If you investigate fatigue failures of metals like aluminum, if you never load the material more than 50% of the yield point of the material then it will have an infinite life (infinite stress cycles). The closer the load on the wheels comes to the yield point of the material, the less cycles it can handle before it breaks. Fatigue strength is a logarithmic curve, so as you approach the yield point, even small changes have a disproportionately bigger effect. The moral of the story, identify WORST-case loads on the wheels and then design so that no part of the wheel EVER goes past the 50% point. A good FEA will identify that and it's why I don't buy the "wheels are consumables" bullshit.

Preach it brother!

[Bartledoo]

Not actually infinite life at any stress for Al alloys, although with low enough loading it may as well be.

[M3 Number 86]