incessant

Hey guys,

I just ran my first autocross, and I love it! I noticed a major problem with my grip. After talking with other competitors, it seems that most people have special tires, or at least stickier tires for these events.

The problem I am running into is product..or lack thereof. I can not seem to find ANY good tires for autocross in 215/60/R15.

What do you guys do for tires?

1989 944 2.7 n/a

sjfehr

It's FUN, isn't it? First, I suppose I should give the standard disclaimer: the single biggest thing you can do to go faster is drive drive drive, and tighten that loose nut behind the wheel. Use whatever tires you have and take as many runs as you can until they're gone. Don't change anything until you have a couple events under your belt.

OK, so real answer... Is this PCA, SCCA, or someone else? (I ask as there are different rules/allowances.) The "tires to have" right now are Bridgestone RE-71R and BFGoodrich Rival S, with the faster of the two depending on setup and driving style. (And Kumho V720 not far behind.) To the point where it's no longer "what tire is in your size" as "what size tires will fit on your car." For a stock 944, you're not going to find anything good in 215/60R15. But, that's precisely why SCCA introduced the +/-1" wheel diameter rule- so cars with odd size tires can run something more optimal. I bet 205/50R15 RE-71R, 225/45R15 RivalS, or 225/45R15 V720 would work pretty well on your existing wheels, though they'll be nearly 2" shorter. Short tires like this would increase your gearing/acceleration, but your gears will be a lot shorter. 225/50R16 would be very close to your OEM ride height if you got new 16" wheels. If you could have bought Turbo wheels as an option in 1989, you can run that size wheel, too; if you can, DO THAT as you can run WAY better rubber on 944T wheels! Wider tires are almost always better for autocross.

For other options Dunlop ZII* is generally regarded as a slightly slower RE-71R, but is very good for autocross and will last 30-50% longer than RE-71R will. (I used to run ZII* before I switched to RE-71R; I really liked them for autocross and they're fantastic on the street, too!) Nexen N Fera SUR4 is a newcomer that's not quite as fast as RE-71R/RivalS, but really cheap for 225/45R15. Hankook R-S3 and Toyo R1R are getting old at this point, but are still quicker than PSS and just about anything else out there that I haven't already named. If you can find any of these tires in a size that works for you, I think you'll be happy. But you'll be fastest if you get new wheels to take advantage of rules allowances and the biggest wheels offered in your model year. BTW, when I say "slower", I'm taking about a less than 1% speed difference- 1% is a huge difference on the autocross course, though.

FWIW, I'm running RE-71R on my Boxster S, and doing extremely well on them in SCCA autocross. And they're downright incredible on the street.

incessant

Thanks so much for the detailed response! Yes I am very interested in continuing the autocross circuit. It is SCCA rules. I appreciate what you said about the loose nut behind the wheel. There is no question that I can run better times with my current tires, as evidenced by the -10 seconds on my final time of the day. I need to learn my car. However, my tires have dry rot and wear bars showing (non inspectable) now so I need tires regardless. I am not so dedicated that I am willing to invest in 2 sets and swap them. The RE71R are certainly the tires most have, but I was warned against them for everyday/highway driving due to excessive wear. I was told the Michelin Pilot SS was a good combo tire.

So my thought is this, I need tires now no matter what. I need a tire for regular road/highway that won't wear super fast, but is also good for autocross. At this point, as you say, I am the weakest link in the times, but the tires certainly aren't helping. I also feel like if I am going to get a good feel for the car and the courses, its hard to do without good grip.

You mentioned alternate sizes for the same rims. Is there an argument for adding wear to suspension/transmission/brakes etc, if i run a shorter tire? Also if I was able to increase my rim size, would I be affected by additional weight?

Thanks again!

mopar bob

If the budget is tight the RS3 would be OK to start out. They are not the fastest tire in the class but they are cheaper and I did 1 class 1 test and tune and 10 races plus DD them on a 911. It was my rookie year and they lasted me all summer. The rears were shot but the fronts were OK but saying that a 911 eats rear tires. I have also run RE11's on my 944 S2 with a 968 motor and would get 3 summers as a DD tire with no Autocross. I always run snows in the winter but O did like the RE11 on the street but they are out of date for fastest times. The RS3's are cheaper. My son like the direzza zii star spec on his 944s when he was auto crossing it a few years ago. I would go wider but keep the tire diameter the same. My son always thought that the 944 should be square with the tires (same front and back).
Since you are starting out and need tires pick one and have fun but the Re71r will be short lived on the street. I'm running the RE71r myself but I only put them to drive to the track race and drive home and install my Super Sports on. It will take some time to get the nut behind the wheel tuned up. Get seat time have fun and next spring when they have a starting line school go and a EVO school. Get one of the old pros ride with you and get some hints and ride with them to see how it is done. Welcome to the club.

sjfehr

I'm in south-east VA and the weather is mild enough here that I can just about run summer tires all year. If you're in Maine, you're going to have to either park it or switch tires when it gets cold. Your best bet may be cheap snow tires on your OEM wheels and a set of cheap track wheels for your summer tires. TireRack has some great inexpensive wheel options and they'll ship w/tires mounted if you order the same time.

Putting on tires that are 2" shorter will drop your car 2" closer to the ground and probably look kinda dumb if that's something you care about. The drop will lower your CG and make the car more stable in turns, and it will accelerate better, but you're going to run out of 2nd gear in a hurry and may have to shift a lot on course. The speedometer and odometer will be off, too. Running 225/50R16 on 16" wheels will be heavier than 225/45R15 on 15" but would be very close to stock size/height and will likely be lighter than your existing wheels (Porsche OEM wheels tend to be heavy). If you get Turbo-size wheels (are they listed in your owner's manual as available options?) you can run WAY wider tires which will have significantly more grip. If you do buy new wheels, bear in mind SCCA requires you to match OEM width and offset within +/-7mm. You can change the diameter +/-1" and run 17" wheels if you'd like. You may get better tire choices in 17" than 16" but they'll cost more, too.

PSS aren't made under 17" but they're more of a luxury performance tire than an actual performance tire and make a lot of compromises. Nobody who is serious about autocross runs PSS for autocross. RE-71R do wear quick, but moreso during autocross than on the street. For most people they heat cycle out and get slow before they wear down to the cords. They also don't suck when it's cold. The old R-S3 was terrible in the cold, but the new compound is better; I don't know anyone that's driven them in cold to talk about them, though. I don't like R-S3 for Porsches because of the relatively soft sidewall, though they're still very grippy tires and really cheap. If you're concerned about cost/longevity, you'd probably be happy with Dunlop ZII* (relatively long life compared to the others) or Kumho V720 (cheap for the performance). Neither will win you a national championship, but they're both proper quick tires.

Tirerack's review:
http://www.tirerack.com/tires/tests/...y.jsp?ttid=202

Auto_Werks 3.6

As a beginner looking for a streetable tire, I wouldn't shy away from the Bridgestone RE-11 either if it comes in a size that works for you. I've been using them on 944 turbo wheels because they come in a 245/45/16. They were good for 18th out of 70 something on raw time the last time I ran them locally. I think historically the RE-11 has some of the best wear. I've been running them on my daily driver's summer wheels for thousands of miles, and they're still hanging in there.

incessant

So.. years later and I still haven’t bought new tires. It’s beyond time. My question is this - The only V rated or better tire in 215/60/15 is the Pirelli P6000 to the tune of $335 a tire. Is it worth that, or should I get an H rated tire for 1/3 of the cost?

I drive this car on the street mainly only in summer about 2000 miles a year.

edfishjr

First off, forget about the stock size. Nobody makes 60-series anymore for a reason. There are other options.

Want massive grip? Get the Rival-S 1.5 225/45-15. It will go on your 7" wide wheels no problem. Very nice road manners, not noisy, etc. That's what's on my phone-dials right now.

Not worried about ultimate grip, want a nice crisp feel for the street, get the 205-50 and save $20 per tire. You will be amazed.

Braymond

Yeah, I agree with Ed here. There's no reason to compromise on tire performance for the sake of installing the stock size. If you have no plans for autocross, that stock size would be fine even if still a bit hard to find. But you can find much better options for both street and autocross by going with either 225/45 or 225/50 series. I will warn you though - the 225/45-15s are very small. These are great for the track, but look kind of silly on the street. The 225/50s options are limited (but not zero) for 15 inch wheels. There are some 225/50-15 tires available that may be suitable if you're only driving 2000mi per year though. Upgrading to 16inch helps a little.

You can find stock OEM Porsche 944 wheels in both 15" (as a spare set) or 16" (as spare or replacement) on FB Marketplace or CL all day. Porsche made 16" phone dials and several other very stylish 16" wheels for the 944/968. I bought the 16" narrow 5-spoke 968 wheels on CL for $600 with decent tires.

Here's a pic of my 944S with the stock 15inch phone dials and 225/45-15 BFG Rival-S tires. They noticeably lower the car and provide excellent grip, but they don't fill-out the wheel wells very well.

I just started autocrossing myself a couple of years ago. I also started with stock 215/60-15 tires and upgraded immediately. I went with the "spare-set" strategy and have a nice set of 18s for the street.