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-   -   What tire size 4AutoX & same width or not? (https://www.rx7club.com/race-car-tech-103/what-tire-size-4autox-same-width-not-615704/)

GoRacer 01-19-07 03:18 PM

What tire size 4AutoX & same width or not?
 
Well after reading and looking at tires and seeing that the stickiest ones can last as little as a few thousand miles at best, it seams the best solution is a seperate set of wheels.

I will start out with Toyo's on my current wheels (S03's are too heavy). When I get track wheels I will get some Falken Azena's. Next year after some seat time I will get Nitto. I'm not shure where the Yoko A048 fit in but they are more expensive and harder to get.

So those of you that have actually AutoX'd multiple setups "yourselfs": :UNCLESAM:
Did you prefer same width or stagger setup?
...if same width, do you prefer 255 or 285 and 17" or 18"? I doubt anyone is running 315's all around, anyone, Beauler maybe? :sadwavey:

Same question for open track or club?

The track wheels i've been looking at depending on size are:
Buddy Clup P1 QF (forged)
Work Meister S2R (i've read forged and semi forged, so don't know for shure)
Work Meister S1 3PC (not shure if center is forged, but the rest is)
CCW 505A (1pc forged aluminum)
Volk Racing GTN (not shure if they are forged but I think they are 2pc)

I'm not shure of the weights on them all. If anyone knows, please post. I know Buddy's are extremely light but they are limited in size and offset.
Thanks for any input. :ylsuper:

Spank 01-19-07 04:55 PM

Tires and wheels
 
It depends on what class you want to run. Stock class is stock wheel size. It is hard to beat an extra set of stock wheels. Tire size would be 245/45/16 in Kumho 710 or Hoosier Autox.

Street prepared you could easily run 275/40/17. I believe that is what I ran for a number of years. That is the same size the Tri-Point RX7 ran for a number of years. Again same tire manufacturer.

285/30/18 is another choice but very little side wall. You can run them all around if you like. If you go wider you should flare the rear fenders.

I have run 245's all around, 275's all around, have tried 335's in back and 285's in front. Now I like 285 in front 315 in back.

So the set up you run will be based on class you run in as well as money you want to spend. Except for the 315 you can run the others with stock fenders just turned in lips.

Allan

GoRacer 01-19-07 06:09 PM

oh wow 285/315's, that's tight. :drool: Do you have a pic whith those wheels? :icon_tup:

I didn't know Tri-Point ran the same size, much less 17's. I know Pettit ran wide rears but I don't think they did AutoX. All the JDM tuner cars i've been able to tranlsate use 235/255 or 255x4 but I can't remember if 17's or 18's.

I was placed in SM2. I currently have Volk Daytona Speed which are not as light as forged wheels. Tires are 225's & 255's. I can fit 235's & 265's but they are slightly taller and i'm not shure if that offsets the gain of the width.

I can do Buddy Club P1 QF in 17x9(+35) and run 255's x4. Their 18x9's are 14.7lbs, not shure how much less 17's are but that's light allready. QF's are special order and even BC USA has to order a minimum from Japan, otherwise I could go through Takakaira but at $650ea retail, they are not as cheap as I thought.

The 2-pc Work Meister S2R in 18x10 is 25lbs (retail $650ea)
The 3-pc Work Meister S1 in 18x10 is 27lbs (retail $750ea)

NeoTuri 01-19-07 10:03 PM

You can rotate your tires if they are all the same size.

scotty305 01-20-07 01:55 AM

My car is mostly stock, so I just run stock wheels, with 245/45R16 street tires.


At least two of my friends (RX-8 owners) are using Enkei RPF1 wheels, 18x9.5 all around, with 285/30/18 Kumho V710 tires. They've been doing well, one of them was regional champ in their class last year (it was his second year autocrossing). I'm not sure if the offset will clear your fenders, but I bet they'd let you try them on your car to see if they'll fit.


As far as staggered setups go, I've read that you should keep the tires consistent with your weight split. If your car has a 50/50 split, stick with the same tire size front and rear. If you had a 48%F /52%R weight balance, run 255F/275R or 285F/305R if you can make them fit. I'm not sure you could shift your weight bias much further towards the rear than that.


-s-

GoRacer 01-20-07 02:47 AM

^ Hmm, survey says: #1 answer :bigok:

That makes sense. Unfortunately, I do not know the corner weights of the car. I'm leaning towards the Buddy Club P1 QF in 17's with 255 all around because the tires will be cheap and the wheels only weigh about 13lbs each. 285's all around is alot more width but will the weight offset the gain?

SPICcnmGT 01-20-07 08:03 AM

Honestly on the AutoX course in a FD you should have enough power to make the car do what you want. It is more of a driving style thing. If you want even, then yes it will me more neutral under constant speeds, but if you go staggered, then you will have to use the throttle to rotate the car. It just depends on how you want to drive.

scotty305 01-21-07 02:07 AM

This website shows what Andy McKee is running. His RX-7 won SM2 at Nationals last year.
http://www.7parts.com/andymckee.html

Bogart Race Wheels 17x11 Front, 17x12 Rear
Kumho V710 315/35 Front, 335/35 Rear
A few of his other mods include wide fenders, GT35R turbo, and 4.77 final drive ratio.


Personally, I say spend time and money driving. Tune your current setup (adjust tire pressure and damping ratios), that should help you decide if you like your staggered setup or not. Buying wider tires will get you fast times, but it won't necessarily make you a faster driver.

-s-

Spank 01-21-07 01:34 PM

Andy
 

Originally Posted by scotty305
This website shows what Andy McKee is running. His RX-7 won SM2 at Nationals last year.
http://www.7parts.com/andymckee.html

Bogart Race Wheels 17x11 Front, 17x12 Rear
Kumho V710 315/35 Front, 335/35 Rear
A few of his other mods include wide fenders, GT35R turbo, and 4.77 final drive ratio.


Personally, I say spend time and money driving. Tune your current setup (adjust tire pressure and damping ratios), that should help you decide if you like your staggered setup or not. Buying wider tires will get you fast times, but it won't necessarily make you a faster driver.

-s-

You cannot run the same as Andy. Andy has a custom front end that allows for 315 and still have the car lowered.

Refer to original post for max size or ask Andy himself.

Allan

GoRacer 01-21-07 05:22 PM

Well the widest I thought of is 315 all around. WHen I checked tires sizes there was one brand in 295 that was 25" in hight but that was it (too limited in choice). 315's ar not much taller then 25" but 335 is taller then I want to go. Anyhow the prices on rims are not much difference in 18x9 vs 18x12, so it's best to decide beforehand. yes, tire prices will vary but then that can vary in the same size to. DMax fenders add 2" which should be enough for 315's in front but that's assumin it won't rub on the inside.

Anyhow no one is going to expect the tires to drive for them. I know there's some guys that have allready gone through this and have tried both setups and different sizes. So if I get their experience then i'm not wasting thousands of dollars switching setups. Besides to go wide requires wider body. That's simple for the front, just replace the fenders but the rear requires body work and paint.

I saw the 7parts site before and noticed the gears. that shure would give the low end v8ish torque I lack but does anyone know what A/R his turbo is? I was debating going smaller. I'll probably just get the RX8 4.44 gears from Mazdacomp.


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