14's or 15's for the track?

joe4agze · Postby **joe4agze** » Thu May 01, 2014 4:05 pm

Hello All,

I'm a newbie to this forum and MX5's.
I've been mainly involved in MK1 Ford Escorts which I have tracked but would perfer not too now thet she is getting a little too old and I believe I csn get much better handling out of the MX5.

I recently purchased a 1990 NA Roadster for Track purposes only.
It came with pretty light 14 inch alloys "BR Sport" or "BR Racing" can't remember now.
The wheels have very bald (Can't see tread anymore) RE001's on them and weigh a total of 13kg's each.
Tyre size is 195/60/14.

My question is for the track should I go for 15's or stick with the 14's since they are light?
I had a bit of a search for 14 inch track tyres and did not find many.
Should I just go to the 15's for the mush wider range of tyre choice and the lower profile?

Thoughts.

Thanks all.
Joe.

kazama · Postby **kazama** » Thu May 01, 2014 4:44 pm

For the track go 15s and never look back

Now you have to decide what width

hks_kansei · Postby **hks_kansei** » Thu May 01, 2014 5:12 pm

joe4agze wrote:I had a bit of a search for 14 inch track tyres and did not find many.

There's your answer.

You'll be faster on slightly heavier 15s with decent tyres, than light 14s with economy tyres.

joe4agze · Postby **joe4agze** » Fri May 02, 2014 7:22 am

Thanks for the replys.

Yes well I guess it's pretty obvious when you start looking a the tyre choices your given!

So now I assume a set of 15x7 with an offset of between +40 to +20 with a set of 195/50/15 or 205/50/15 is what I'm looking for.

Any recommendations?

Thanks all.
Joe.

Postby **beavis** » Fri May 02, 2014 5:28 pm

Aggressive (requires guard roll): 15x9 rim with 225/50/15 tyres

Not as aggressive (guard roll possibly required): 15x8 rim with 205/50/15 tyres

Aim for around +30 offset. One of these options is the fastest package for an MX.

16bit · Postby **16bit** » Fri May 02, 2014 9:51 pm

205 50 15's on 8's is a proven combination.

plus 20 to 36 is fine. fastest combo seems to be plus 36. there are a few options at that size.

949 racing 6ul
and plenty from here http://www.good-win-racing.com/Mazda-Pe ... heels.html

Guran · Postby **Guran** » Fri May 02, 2014 11:45 pm

First things first. What type of track duty are you looking at doing? Is there a particular category or class you want to compete in? Does that class allow different wheel sizes?

Personally, I had no problem getting decent track tyres in 185/60R14 over the last five years. My favorites were Bridgestone RE55S (R spec) and Dunlop Star Spec (S spec). Even the old RE001s were decent street tyres and very cheap too. Don't write off the 14s too soon before considering your options.

manga_blue · Postby **manga_blue** » Sat May 03, 2014 3:20 pm

x2 with Guran on the 14s. Over the past 2 years Celluloid Retina and I were nibbling back the NSW club's Wakefield modified class lap records. These are reasonably stockish cars, CR was running 185/60 Star Specs on 14x7s and I was running 195/50 on 15x6.5s. These times were plenty faster than a lot of cars in the class running bigger wheels and rubber. At the same time Guran has been lowering the standard class lap records with 185/60 on 14x5.5 daisies and generating the same sorts of corner Vmins as we were.

If you're driving a relatively stock car then tyre + wheel weight and driving technique are far, far, far more value than big rubber.

Spend your money on seat time for the first season at least, it's much more fun and it's much more productive.

joe4agze · Postby **joe4agze** » Sat May 17, 2014 8:54 am

Great information guys. Thank you.

I did manage to get hold of a set of 15x6 rims for a good price so I guess I can experiment between the 14's and 15's.
The 15's with shoes weigh in at 15 kg so 2 kg's more than the 14's so I'm assuming I be able to feel the difference between them. It will be interesting.

The type of track work ATM will be "Speed off the Street days" until I feel like I need and have time and money for more than that.

Thanks once again.

Guran · Postby **Guran** » Sat May 17, 2014 9:19 am

Something else to keep in mind which is doing my head in at the moment: Yokohama A050s in 185/60R14 are $252 each, but 195/50R15 are $332 each. That's $320 difference per set and I doubt the extra 10mm width will make any real difference, especially since the 15s are a little heavier.

Joe, if you're talking speed off the streets at Wakefield Park, then you would be better off coming to our MX-5 Club of NSW trackdays instead. They cost a little more but you get a very well run day, scrutineering, drivers briefing, official laptiming, run groups of even pace so plenty of clear laps, lots of MX-5s (typically around 60), and endless supply of great advice. You won't regret it.