John's CS BRZ progression

[bimmer635csi]

Originally Posted by AustinTX

Like others have said, I am comparing to known fast guys within my region. I'd also like to say that having a codriver at local events doesn't always work out in your favor for the reason you stated. Hard to focus on your own development when you are busy supporting someone else's efforts between runs. That, plus street tires don't really like the extra heat generated by double driving. Best to drive alone unless your codriver is providing good course feedback, good driving feedback, or the car

He's providing tires, so I couldn't say no. But the good point is that the next event the car will have new tires, so I'll be sure to do a PAX vs. PAX and see where we fall out. Thanks to all for another useful piece of advice.

[AustinTX]

Originally Posted by bimmer635csi

He's providing tires, so I couldn't say no. But the good point is that the next event the car will have new tires, so I'll be sure to do a PAX vs. PAX and see where we fall out. Thanks to all for another useful piece of advice.

From your youtube channel, I found you are from SA and were at the Spokes event on Sunday. You can compare directly to my times

[bimmer635csi]

Originally Posted by AustinTX

From your youtube channel, I found you are from SA and were at the Spokes event on Sunday. You can compare directly to my times

Dang, the cat got out of the bag!


Seriously though, Prius tires do not compare to anything that a competitive autocross car would have. So there wasn't much point to make that comparison. Also, my driving experience is next to nil, so to compare my time and your time is similar to comparing chalk and cheese. Hopefully it is hot and dry at the July event so I can make a somewhat reasonable comparison vs. Sunday.

[AustinTX]

We are all here for the same reasons - we enjoy driving our FRBSZ's at autocross and want to get the most out of them at events. I made this thread to share what I have learned and to learn as much as I can from others. Hopefully, it has been beneficial to all - I know I've learned a ton since picking this car up in November

Chris - feel free to get a ridealong at the local events. You learn a ton from riding along and taking riders when you are new to the AX game.

[automatic]

Originally Posted by AustinTX

I fully expect that any strut based street class car on street tires being used for autocross will wear the outside shoulder significantly faster than the center of the tire. I usually change tires long before they get below 4/32nds anyway

With that said, my 75 run 235 Z2's had VERY even tread wear when I sold them at 5-6/32nds. I expect the RS3's will wear the shoulder much faster due to the flatter tread profile. Either way, I will buy the tire that makes the car the fastest.

I tend to try to use a tire until all the tread is gone (money limited) so I dont change tires that often. Would a 225 RS3 be a better choice than a 245 then?

[AustinTX]

If you want the tires to last a long time, I would run the Z2 or some tire that has a more round profile. The RS3's flat profile will wear the outer shoulder very quickly on a camber limited, softly sprung car. If you are driving on them daily, I'd suggest more strongly to pick the Z2 (or similar) due to deeper tread depth and reduced propensity to heat cycle out. I'd also suggest staying within the tire's minimum width recommendations regarding treadwear on a daily driven tire.

[Jawnathin]

Very interesting insights into the tires. Thanks for sharing. Was really torn between 235/40/17 Z2s and 245/40/17 RS3v2s and its nice to hear you had experience with both.

I settled upon the RS3v2s, because I wanted a wider tire that wasn't as sensitive to heat. They were also a little cheaper . But your concerns about shoulder wear is concerning as my car will be co-driven and I expect a lot of runs. Depending on the club, 20-25 runs for a day between the two of us. Not daily driven, but occasional street driving along with the commute to and from events. Will be swapping the stockers back on between events, but I may have a lazy day or two and leave em on.

The order hasn't been fulfilled, I still have an opportunity to change. If you had to buy a set now, which would you take?

[AustinTX]

I don't know how many runs you'll get out of either tire, but I expect 100-150 would be a safe number. Maybe up to 200 runs depending on many factors such as car prep, course surface (asphalt wears them slower than concrete), and how hard the drivers are on the tires. I'd get the RS3's myself.

[Jawnathin]

Thanks! I'll keep the RS3v2s on order. Very excited to try em out. I've only driven the car on the OE Primacys and while I've been reasonably quick on them (considering what they are), it was like bringing a knife to a gunfight. These will level the playing field by quite a bit.

Though with the Z2 Star Specs coming out for next season, I may have this same debate again!

Thanks again and looking forward to tracking this thread and your entry into Nationals.

[vroom4]

We are at about 180 runs on our Z2 and still putting down fast times. Need to flip them for the packwood tour this weekend so we have shoulder again.

[chucky12012]

John,

We should try and coordinate and make one of the two remaining College Station practice events. If we could get you and Jason along with Andy and myself, we would be able to get some really good info at a mirror site to Lincoln at College Station. We'd have plenty of seat time with a prepped BRZ, FR-S, Z and RX-8. They have a practice July 26/27 and August 9/10. Let me know your thoughts on trying to do this. (This time Andy and I will try and not break our cars)

-Chris

[AustinTX]

I will definitely be at either the 8/9 one or the pre-nationals one (if they have it this year). I'll do 4-6 runs and head home, though. I don't plan on doing any car swaps or anything. I tend to book several tnt sessions at nationals for final calibration

[chucky12012]

I'm not sure swapping is necessary, but it will be good to have some benchmarks.

[markw]

Originally Posted by bimmer635csi

Dang, the cat got out of the bag!


Seriously though, Prius tires do not compare to anything that a competitive autocross car would have. So there wasn't much point to make that comparison. Also, my driving experience is next to nil, so to compare my time and your time is similar to comparing chalk and cheese. Hopefully it is hot and dry at the July event so I can make a somewhat reasonable comparison vs. Sunday.

If you haven't done this before, get an instructor driver to go with you, or go for a few rides at a practice. It will help immensely. If John is comparable to Andy Hollis, who I assume is the "Andy" mentioned, then he's one of the fast guys. If you can get within a couple seconds of him, you'll be doing great. Don't be too proud to not ask for an instructor though, or even a ride as passenger. It will reveal all sorts of things that you are missing.