That is a common theme. I remember Car & Driver being really underwhelmed with the new 3-series when it first came out, because they thought it had lost some of its responsiveness and "feel".

Weight... heh the 350Z could stand to lose a few pounds, as well. Still, it's a hell of a car for the money.

 

Actually the 350Z is not that heavy, we weighted it before we started tearing it apart and with the heavy 17" wheels, it weighted about 3200lbs. Just taking the spare tire, tools and rear floot matt and cover out, reduces weight by about 40-50lbs.

Our car, with rollcage, and full interior should weight around 3000lbs when it is done.

 

Buub,

What was Fordahl's opinion on whether the "R" compound would be effective for A/X or not? I would imagine they have a lot of experience with the different tires and compounds.

BC

 

They said it shouldn't make a big difference for autocross, but driving the A on the track would heat it up too much, too fast, and ruin it. He didn't think driving R in autocross would be a problem.

I was borderline anyway. Hoosier's site recommends the R for heavier, high horsepower cars. We have heavy cars. We have moderately high torque and horsepower (not a Corvette, obviously, but not standard Miata either).

I guess I'll find out in a couple weeks. :-)

 

Buub,

I think you probably have your answer, they know their stuff. I'm looking forward to seeing how you do on the new rubber. I think you are going to have some big fun.

BC

 

R compound tires on autox will make about a 3 second a run difference on a 60 second course. Yes, they are very good.

Carter Thompson, who placed 6ths at nationals last year (behind all the S2Ks), runs Hoosiers (275s on 17" sized wheels (7.5" front, 8" rear)).

 

Well, $1200 later I just picked them up today. So they better help!

 

Buub,

When's your first appearance with the new rubber?

BC

 

I have these shiny new Hoosiers sitting in my garage without a scuff mark on them. That just doesn't seem right.

BTW, my Proxes T1-S were fantastic up in Vancouver this past weekend. Of course, their surface is very rough, so probably anything would stick well there. But on Sunday I rode with Carol Leuty on two runs to see her technique, then I went and beat her on my first run in raw time. It was a big step forward for me. Of course, my car has a lot more power, so indexed she was still way ahead of me, but it was a little personal victory to put down a respectable time.

Anyway... I'm thinking July 4th and/or the 10th/11th. I have a Mountaineers Singles outing this coming weekend. Have to do something besides car stuff every now and then!

 

Buub,

Lookin' forward hearing your evaluation of the Hoosiers... You're right, need to do something other than car stuff every once in a while... so I'm headed out to Indy for the USGP... oops, that's still car stuff isn't it? Oh, well too late to try another gig anyhow!

BC

 

Hey, that still sounds like a helluva lot of fun!

 

I have been trying the Kumho's for several races now, along with advice from Guy Ankeny. Kumho's suck is the consensus. My times have increased by about 1.5 seconds. Had 2 National champs drive my car and they could only get about a half second better. With the Hoosiers I was 95-96% of pax, now sitting at 91-92% on the wonder Kumwhores. Save money, run faster buy Hoosiers!
Same size all around seems to help the car be more neutral, was loose in the rear till Guy had me up tire pressures, now at 47/41. Now it won't run right due to crappy tire formula

 

rktjhn,

I've been taking your input and applying it to my set-up, so I regret to hear you are having a negative experience with the Kumhos. I've been wondering if I made the correct choice going with the Hoosier 275/35-18 A3S04s all around... just because of short tire life span... not because of tire performance (once I figure out the unusually high tire pressures)... and I was considering Kumhos for my next set. Thanks again for keeping me from going in the wrong direction... I certainly appreciate it when people come right out and say it straight up.

BC

 

Hoosiers love high pressures!

 

Scary pressures, but pyrometer agrees Hoosiers love big pressure.

BC

 

So is this a Hoosier only thing, with the 275/40s? I run 245/45 Azenis Sports and am running 38/35psi cold.

 

It's a hoosier thing, not necessarily just 275s. I ran 245 45 16 (I think that's the size) on my camaro and had to run them up that high, 48-50 up front, 42-46 I think in the rear.

Kumhos like lower pressures, I run 37/33 in my 245 Victos. I do not have any experience with Azenis though to give a recommended range on them.

 

So, what are the concensus best pressures for autocross when running Hoosier 275/35-18s under a 350Z?

 

OK, after two days of autocross this weekend, co-driving my car with a very experienced driver, do Hoosiers make a difference? Hell yes.

Of course, the difference is subtle. I could not suddenly make 90-degree turns at 6 Gs. I could still out-drive the tires if I got too wild. However, I could make maneuvers under power that would have had the car plowing, because of my turning beyond the tires' grip, had I been running street rubber. I was quite amazed at the moves I was able to execute successfully, while keeping on the throttle. Of course, at least half of that was co-driving with a very experienced driver -- it helps to feel and watch what someone else does.

However, on one run, I rode with someone else in a Mustang Cobra running on street tires. She was an excellent driver, but this wasn't her car, so she was not totally familiar with it. It would plow pretty hard on some of the turns, and I could tell she was frustrated with the limits the tires were giving her. This comparison made it clear to me how much higher the limits were on my new Hoosiers.

As far as pressures...

I do not know why, but I am getting different results from what I am hearing here. Of course, I am running R-compound 304s, instead of A, but I would not expect that to make a difference with pressures. Abe and I determined the perfect pressures for my car, keeping the tires warm, was 40 front and 36 rear. We let air out after every run to keep the pressure at 40/36 warm. He felt, and I agreed, that this gave us the best grip. I am going to have to get some insulating tire covers, now, to keep the tires warm when I drive solo.

I am running Hoosier RS304s, 275/35-18, all the way around, on Track wheels.

 

Tire covers actually, to my knowledge, are no longer legal (as of 2004) but I'd have to look up the specific rule.

As for pressures, you can run them that low, but watch out for wear on the outer edge of the front tires, EXTREME wear is possible running that low, as well as cracking the sidewall by running too low and rolling over. I just saw a picture of some hoosiers that did just that a week or so ago.