dp1 tires (reference/research/reviews)

[whataboutbob]

Moved from 245/40R17 A7s to 275/35R17 A6s for the start of the year. 30mm tire all around really helps.

[dp1]

Originally Posted by whataboutbob

Moved from 245/40R17 A7s to 275/35R17 A6s for the start of the year. 30mm tire all around really helps.

Dat wink...

[whataboutbob]

Off topic, but here you go...

[ame]http://youtu.be/g-o-hHRvKOs[/ame]

[dp1]

Originally Posted by whataboutbob

Off topic, but here you go...

Not at all off topic - this wins my Internets for today. I'll put this in the videos thread, thx

[dp1]

Originally Posted by whataboutbob

Off topic, but here you go...

What's your camber/toe/caster?

[whataboutbob]

Originally Posted by dp1

What's your camber/toe/caster?

As much as I'd like to share, those were some parameters that took some time to perfect and might be one of my competitive advantages against other twins in the class. I don't want to share the exact values right now, but here are some hints.

Camber: FT more than 3.5, Rear more than 2.5
Toe: A very small amount out on the front, and about twice as much in on the rear.
Caster: I have the Whiteline offset busing on the front LCA, and the Raceseng CASCAMs. They are both maxed our on caster right now, more than +6.5.

[dp1]

Originally Posted by whataboutbob

As much as I'd like to share, those were some parameters that took some time to perfect and might be one of my competitive advantages against other twins in the class. I don't want to share the exact values right now, but here are some hints.

Camber: FT more than 3.5, Rear more than 2.5
Toe: A very small amount out on the front, and about twice as much in on the rear.
Caster: I have the Whiteline offset busing on the front LCA, and the Raceseng CASCAMs. They are both maxed our on caster right now, more than +6.5.

Thanks, I understand - I tried -3.4f/-2.7r per @CSG Mike suggestion, with max caster on Ohlins (adds about 1 degree), shaved and heat cycled Toyo RA1, and it worked great on track. Didn't scrub much rubber in about 8 track and 1 ax day with them, need to push harder. Will look at the pyrometer more closely but I'll go with -3f/-2.5r this year considering my car is primarily a daily driver. I also have a little stiffer springs now, from 343lb all around to 380lb f/425lb, struts revalved, but that shouldn't have too much impact beyond helping with rotation...little bit in fast corners and more in slow.

[rx3]

Toyo Proxes R888 http://toyotires.com/tire/pattern/pr...petition-tires
@glamcem "I know the R888s are notorious for being inconsistent and consistency is the main reason I picked NT01s over the hardcore lower TW R comps.. it seems like the NT01s are still the magic tire when all considered :/"
@rice_classic "I'd argue that the R888 is garbage in any weather, but that's just me. If someone gave me a set for free I'd immediately give them away."

I don't know about the track, but the Toyo R888 is definitely a very good tire for autocross-like purposes. It has good grip from the start and is even remarkably grippy in the wet (apart from hydroplaning at high speeds).
Practically everybody at our events is running on Toyo R888.
Occasionally one is running on Yokohama A048, but I don't recall anybody ever winning on those. The Toyo's don't do well at low tire pressures and high temperatures, but low tire pressures can be avoided and high temperatures don't occur on short 'stints'. Here's an example where the tires still reached close to 1 g at some corners despite being very wet.
[ame="https://www.youtube.com/watch?v=nlW2pdMuKzs"]BRZ in another wet autocross - YouTube[/ame]

[dp1]

Originally Posted by rx3

I don't know about the track, but the Toyo R888 is definitely a very good tire for autocross-like purposes. It has good grip from the start and is even remarkably grippy in the wet (apart from hydroplaning at high speeds).
Practically everybody at our events is running on Toyo R888.
Occasionally one is running on Yokohama A048, but I don't recall anybody ever winning on those. The Toyo's don't do well at low tire pressures and high temperatures, but low tire pressures can be avoided and high temperatures don't occur on short 'stints'. Here's an example where the tires still reached close to 1 g at some corners despite being very wet.

Great feedback and driving, thanks. I'll plug your comment into the 1st post. I've used R888 on track with Lotus Elise couple of years ago and they worked well for me. Also know a few Loti owners (better drivers) who abandoned them due to sensitivity to pressures and uneven wear but they are popular, also since staggered sizes for Loti in sticky rubber are limited. Hope others who used them for ax/track with the twins will also chime in.

[Alan]

Originally Posted by Alan

Feedback will come evening of the 29th after two days at track.

Well, I promised feedback, but unfortunately there isn't any good information. Temperatures never got above 45 degrees this weekend and due to some on-track incidents (not that I was a part of) I never really got into a rhythm. so the experience isn't really helpful.

Will report back next month after Summit Point.

Side note - MikeCSG set me up with some CarbotechXP10s which worked great to and from the track and still had more bite at 30 degrees than the Ferrodo 2500s I used last season. Hopefully, they continue to perform when it gets hot.

[fasteddy]

I have to say thank you very much for doing this, it is a very good resource. I am currently running Michelin pilot supers sports and overall I am quite happy with them. The only issue I have is that after about 15 minutes on the track they seem to get overheated and slippery.

Does anyone have a good suggestion for an upgrade from this for something that would take the heat better?

I used to run Bridgestone RE01R's and RE11's and they get overheated after by 15-20 minutes on track as well.

[dp1]

Originally Posted by fasteddy

I have to say thank you very much for doing this, it is a very good resource. I am currently running Michelin pilot supers sports and overall I am quite happy with them. The only issue I have is that after about 15 minutes on the track they seem to get overheated and slippery.



Does anyone have a good suggestion for an upgrade from this for something that would take the heat better?



I used to run Bridgestone RE01R's and RE11's and they get overheated after by 15-20 minutes on track as well.

My pleasure - I was happy with Toyo RA1 and about to try Nitto NT01 this year for track, but they will wear faster with street use. I use PSS on the street and for wet track. If you don't want a separate set of wheels for track, there are a few good choices in UTQG 200 that work better than PSS while still summer street friendly (see above).

[dp1]

Bimmerworld has Continental Challenge (rebranded Hoosier R7) take-offs with 2-4 heat cycles for sale. Got a set of four 225/45-17 for under $400 shipped.

Update: Wow, the 25% off deal seems to have closed already, but they still have the same tires for $100 each, so should come out to just under $500 shipped in the US. The sales rep said they came off the cars that raced at Sebring.
http://store.bimmerworld.com/clearance--used-c21.aspx

[dp1]

Just had my old Michelin PSS with 4/32 tread (used for 12mo on street an couple of ax days, Apr-Nov) replaced with new...big difference...more comfortable, stickier and less wiggly on scraped highway surface (-3f/-2.5r camber).