Used Spec Miata tires - Budget racing or a terrible idea?

[1600sammy]

Hi,

I've been messing around with autocross for the past year and half and I'm finally at a point where I'm growing frustrated with the performance of my old and hard tires. I'm driving a '69 1600 in the HS stock class. It seems that new tires (and likely wheels) are the answer, but I've been having a frustratingly hard time finding a reasonably high performing wheel to fit on my stock steel wheels. A fellow racer suggested that I could get lightly used spec miata tires for a song (about $20 a pop). These are 205/50/15 R-DOT tires.

So my questions are:
1) Will these tires fit in the wheelwell?
2) Are there any suggestions for a reasonably low cost 15" wheel appropriate for these tires?
3) Is this a wildly stupid idea?
4) If so, are there any better suggestions (that don't cost a fortune), either for tires that will fit the stock wheels or for wheel/tire combos?

Thanks,
Eric

[Alvin]

for stock wheels, try running the Dunlop Direzza Star Spec Z1 in either 185/60/14 or 195/60/14:
http://www.tirerack.com/tires/tires.jsp ... ake=Dunlop" onclick="window.open(this.href);return false;


a 205/50/15 tire may/not fit depending on the wheel specs
Popular 15x6 Panasports in +15 offset are run usually with no problems on 195/50/15 tires

[fj20spl311]

I'm driving a '69 1600 in the HS stock class.

2) Are there any suggestions for a reasonably low cost 15" wheel appropriate for these tires?
These are 205/50/15 R-DOT tires.

Thanks,
Eric

Can run HS with 15" rims SCCA says NO! Are you using their rules?

[1600sammy]

Thanks for the responses!

Alvin, A local tire shop that sponsors the autocross had given me the impression that a 185/60/14 or 195/60/14 tire on stock rims would be borderline unsafe on stock wheels and would curve the tire excessively in order to fit on the rim. Is that not your experience? Panasports would be lovely, but they seem pretty pricey. I saw an advertisement locally for a set of Z swastika tires <http://eugene.craigslist.org/pts/3296048470.html> for about $250. Do you suppose there's any chance of everything fitting with those tires? Judging from the information here <http://www.311s.org/wheelsfaq.html> they have an offset of +12mm. Would that cut it?

Phil, you're right that switching wheels might make me change classes, but that's not such a big deal to me. I think I'd much rather have a car that doesn't swing from understeer to oversteer and back again when I try to push it.

[Alvin]

i can't comment on the performance of the 185 or 195/60 tires on stock, 4.5" width rims, I just know that a few roadsters run these with no problems on the street.
For all-out performance on the auto-x it would be wise to mount them on the widest wheel possible to reduce sidewall flex like you said.
Swastika's do fit pretty well on roadsters...195/50/15 would be the limit from my experience

[fj20spl311]

IMHO,
Get the 6 spoke wheels



I really like them on a roadster....and If you can swing it get the 15" for auto cross....

[1600sammy]

Thanks for the answers. It sounds like the 205/50/15 tires would be pushing it and I might run into fit/interference issues. If I'm not going to be able to run the sticky rubber it might be smarter to stick with the 14" 6-spokes and the star specs.

Do you know if I would need to change the studs to run the 6-spoke or the swastika tires? Or would it just be a drop-in replacement?

--Eric

[fj20spl311]

You either need to change the studs or buy "special lug nuts" IIRC the outside of the lug nut is larger than a normal mag lug nut.

Lots of discussion on this site about making them fit...and pictures of them on cars.

[DatsunBucky]

FWIW, running an autocross with "race" tires could very well create driving habits that when engrained in the cranium, are very hard to replace with correct ones. My recommendation would be to learn to drive on your old, slippery tires, then change over to sticky ones. However, the rush of having sticky tires is absolutely a siren song.

Be strong. Be brave. (cajun accent) "You can do it!"

[Gregs672000]

I have the 6 spoke ZX wheels on my car. You must get the correct shouldered lug nuts in the Roadster thread pitch. Don't recall where I got mine but someone will hopefully chime in... They do exist. FYI, I have two, slightly bent wheels you can have. I mean very slight, but enough that they will work on the rear fine but not the front without a little shimmy. I could not put them on the rear of my car because that set is modified to fit my flares, so I got an unbent pair for the front. They are hard to find unbent. They guy went through 6 wheels before he got me two, so keep that in mind. Anyway, yours for shipping costs (probably need to find big boxes) they are just sitting in my garage. No caps.

[1600sammy]

Bucky, I know! That's why I haven't upgraded tires till now. I won't say that I'm any good at it, but I managed to race the whole year without spinning out, so I must be ready for an upgrade!

Greg, thanks for the kind offer. I'm going to go check out some wheels this weekend and if they're not straight I may take you up on that offer. From pictures, at least, they look pretty unmolested, so I'm hopeful that they'll be in good shape.

--Eric

[Gregs672000]

My pleasure. I was lucky enough to find a guy in Texas I think it was who was willing to spin each one on a balancer. He was a Z car reseller and very honorable. I think I may have posted something to that effect on the list at some point.

[1600sammy]

Hi,

I finally got the wheels! In the end I decided to go with the swastikas. I like the look of them and I like the way that the gold accents on them go with the red paint. The wheels came with 205/60/15 tires, which it seems likely won't fit, but perhaps I can use them to get a sense for what will. Any suggestions for a good source for the correct lug nuts? Any chance that a local NAPA or tire shop would stock them?

Thanks,
Eric

[Alvin]

nice.
don't forget to update us on your new experience with the stickier rubber!

[Gregs672000]

I kinda doubt you will find the correct shouldered lugs locally. One POSSIBLE alternative if you can't find them is to use what are called Craiger washers... They are very thick washers that fit around the lug nut and shoulder them against the hole in the wheel. I use these in the rear of my car because I run spacers and longer studs. I modified the wheel by removing the inner shoulder to allow the longer nuts to go beyond the back of the wheel and through to the spacer without bottoming out on the brake drum. In my case, without modifying the wheel the longer lug nuts I have would bottom against the wheel and not really be tight. Make sure you get this right. I had a buddy's wife lose her rear tire on the freeway (iron cross z wheel) by using the wrong pitched lug nuts. Thankfully nobody was hurt.

BTW, those wheels will look great on your car!