Autocross tyres on stockbodywith
 

Any tips on tyrechoise.

When we are autocrossing in PCSweden it aint allowed too use r-compound tyres.
My car is a stockbodied 75 911.Last year i used Toyo Proxies TS-1 205/55 on cockicutters 6*15/7*15.2,0bar in front

This year I will use Fuchs 6*16/7*16 it semms like 205 is the widest tyre that will fit the body at the rear anyway.

Either I go for the Toyos again 205/45or 50*16 och Bridgestone s02 in the same dimension.

Open for suggestions on tyres, make, with,profile, pressure etc but I´m not willing to alter bodyshape.

I think you'd get some more responses in a 911 forum, lots of guys in my region auto-x with 16s, so I'm sure the info is available.
My region of PCA (near Seattle) has 3 categories that only allow non-R compound tires, the most competitive seem to be Bridgstones. I won in my group on S03's, and other people seem pleased with them as well. I don't have any experience with Toyos, nobody seems to run them here.
If you have mostly dry conditions, I think you can be competitive with a lot of different tires, but for rain the Bridgestones seem to have an advantage over many others. Why take a chance?, if you want to win, get S02's or S03's (if your car is otherwise competitive.). My friend bought Yokahama AVS Sports, and he's 2 to 3 seconds back when it's wet, but right up front when its dry. The RE730 seems really good too, for quite a bit less $$.

My experience with a 1974 "narrow body" was that 6" front and rear worked fine. Only "some" 7" wheels will fit into the rear fenderwells as you have discovered. I know elsewhere there have been discussion that would list the various "offsets" that would make this work. I used a set of 911"R" wheels, 7x15, with a 225/50-15 tire in the rear.

Why the step up to 16". A 205/50, if allowed, on 15" wheels will provide just as much "width" but also provide you with better acceleration than upgrading to 16" wheels. Just a thought... Do you even need to use Porsche wheels? Perhaps an aftermarket wheel could be custom sized for your need.

See if you can buy the Falken Azenis. I have driven on them in numerouse autocrosses and they feel like a R compound tire but is not. I believe they have a tread rating of 180

Here are a couple of links

http://www.discounttiredirect.com/di...ypeCode=FALHZ5

http://www.discounttiredirect.com/di...ypeCode=FALHV2

Those are still the tires to run at National Level SCCA SOLO II street tire class in the US.

The reason why I will go up til 16" are that the Toyos i used bend the sidewalls so the tredpattern wasn`t in contact with the tarmac.Cos of that i will use 45 profile and if I use 15" gering will be a problem:On the autocross in PCS topspeed is often whitin 2 gear and if gering is alterd I need to shift between second and third maibe 4-5 times on a run (915 gearbox soon with factory shortshift and harder bushings) and downshift sideways isent the eseyest task on my gearbox.

A pair of R wheels whould be nice but is out of my wallet.

Thanks//Homegrown

Racer

My experience with a 1974 "narrow body" was that 6" front and rear worked fine. Only "some" 7" wheels will fit into the rear fenderwells as you have discovered. I know elsewhere there have been discussion that would list the various "offsets" that would make this work. I used a set of 911"R" wheels, 7x15, with a 225/50-15 tire in the rear.

Why the step up to 16". A 205/50, if allowed, on 15" wheels will provide just as much "width" but also provide you with better acceleration than upgrading to 16" wheels. Just a thought... Do you even need to use Porsche wheels? Perhaps an aftermarket wheel could be custom sized for your need.


__________________
1978 Euro SC Coupe