SamG

Wow lots of great feedback! I also suspect at least during the morning runs there where still several wet spots on the track and then a cold wind came up in the afternoon probably not the best test of the new car and the tires. I had a couple of clean runs that I really didn't think I could have pushed it any harder and was almost 2 seconds off pace with the fastest time of the day set by a Porsche Cayman.

Yes sorry I did mean PSM not PSE. I'm still not familiar with the settings on the car I really neat to say I first turned the ESC off and then tried with both ESC and TC off.

I will put the cup 2's on and get an alignment before the next event in March and hopefully get a lot more seat time in as well.

Kerry

Tom, what about using the A7 in 235/35R19 front and 315/30R19 rear? That's what I was hoping to use on my new 19" rims.

Mike in CA

Just to butt in here with my own opinion, I wouldn't decrease the size of the front tires while increasing the rears. You'll end up with more push and especially for autocross, I find it's nice to have more front grip at turn in and a bit of oversteer to encourage the car to rotate in slow, tight corners.

Mussl Kar

The Dunlop tires must need a ton of heat because they totally suck in 40-50 degree weather. At the last Porsche autocross here there were 3 DBM 2015 GT3s. Mine with the Dunlops and the others with the MPSCs. The other 2 drivers run with all nannies on and they rely very heavily on them in almost every turn. I turn them all off because that is the only way to learn what the car is all about.
I was posting times within a .01 of one of the drivers and far ahead of the other. All three of us had the same experienced driver as a passenger and after he rode with me he said they both had a lot more grip than my car. I did not think of it at the time but I should have taken a run in one of the other GT3s.
My RS will still kick the crap out of the GT3.

Tom Tweed

^^^ Yes, this is my thinking, too, Mike. I talked to Jeff Speer at Hoosier, hoping they would make a 265 A7 in 19" for the front of the GT3 this year, but he said no, their 19" sizes are set for 2016, but they are going to add 20" sizes this year--first for the Corvette, and then for Porsches. I'm hoping they will make 20" A7s in 265 and 325 available soon, then I will switch to them and use the 19s for street tires. Meanwhile, I have some R7s on the 19" rims I bought that still have some life left to hopefully get me through until then. They have 12 heat cycles on them already, and it will be hard to get enough heat into them on cold days to work well, so I may get frustrated and have to go in another direction after a few events, we'll see. It's supposed to be 72F here in San Diego for our first event this Saturday, so they might work OK.

My backup plan is to keep pestering Bridgestone to make the RE-71R in GT3 sizes, and those may become available before the Hoosier A7s, who knows? They said they were expanding that line soon, also. My other hope would be for the Kumho V720 or V710 to become available in the right sizes. I started a thread here to get help with badgering the manufacturers to make more sizes for the new Porsches, and any other autocrossers/track guys here are welcome to chime in: https://rennlist.com/forums/991-gt3-...facturers.html It would be nice to have some other choices for our cars than MPSC2 and Trofeo R or Dunlops. The more requests they hear the more likely they are to manufacture them, I figure.

TT

Tom Tweed

That is another of my "backup" plans, Kerry, if the R7s don't work well and no other alternatives come up in the next few months. If you try that combo, please report back if it understeers badly. Maybe going to the softest sway bar setting in the front and the hardest in the rear would get the car to a reasonable balance for AX, I don't know, but I wasn't going to try it until I gave the 265/325 R7s a try.

TT

452gt3

Wow! Tom on Hoosiers sounds like TTOD combination. See you there Sat. I will still be on street tires.

Tom Tweed

No worries, Mike. I've got all my excuses ready when I fail--I couldn't get the tires up to temp, they're old and heat-cycled out already, it was a 914 course, the sun was in my eyes, that cone jumped out into my way, I'm too old for this crap, the young guys are too fast, yada, yada, yada....

C'ya,
TT

Mike in CA

Hey, those sound like my excuses...

Kerry

Will do, Tom. I'm addicted to the grip of the A7 so I hadn't really thought about how it will increase understeer, but it makes sense that it would. Spring comes later in Illinois so it will be April before I find out how bad it is.

SamG

Which 19" wheels are everyone using? If I end up buying a set of tires for autocross it sounds like buying 19" wheels would be the best choice for upcoming tires.

Tom Tweed

There are several threads in this forum about fitting 19" wheels for the track that you can check out. Most of the custom wheel manufacturers can take care of you, like BBS, HRE, Forgeline, and Finspeed. Forum sponsors HRE and Race Tech Forged have a number of threads going on showing their products, or you can visit their websites. If you have the ceramic brakes, the fitment can be tight, but with the stock brakes, there is only a clearance problem with the rear toe arm where the bolt through the link needs to be reversed. Here's a few threads for reference:

https://rennlist.com/forums/991-gt3-...-prep-diy.html

https://rennlist.com/forums/991-gt3-...ck-wheels.html

https://rennlist.com/forums/991-gt3-...ited-time.html
https://rennlist.com/forums/991-turb...ck-wheels.html

https://rennlist.com/forums/991-gt3-...th-pccb-s.html

HTH,
TT

HRE_Jurrian

To comment on what Tom Tweed mentioned in regards to 19" wheel fitment - the clearance to the brakes is very tight, but the wheel that we squeezed on this GT3 in 19x9.5 and 19x12.5 clears brakes just by a few millimeters. Here's a few photos:











There's not going to be a ton of wheels in the market that can clear these brakes, but luckily these R101's do

Bokke

Doing my first auto x in a couple weeks in my GT3, so thanks to all who posted in this old thread.

Would be interested if there are others with updated thoughts or advice....

Cheers.....

robmypro

I run the Dunlops and the car is on rails. But you need to get some heat into them, just like any other performance tire. When you do, the car hooks up in an almost crazy manner. It is at this point that I think "damn, I should have got the LWB seats." You need to be strapped in this thing or you are going to move around.