Will 15's fit my big brake sport?

Technical Area Wheels, Tyres & Brakes
2

Hi everyone.

I am looking at replacing the standard 16 inch alloys on my 2003 sport for a set of wheels that are 15inch, 7" wide and offset ET20 with 195/50x15 tyres.

I have spent hours searching if these will fit under the arches without any modifications and if they will also fit over the big brakes.  

There is so much information but none of it makes much sense or can give me a definitive answer.  Does anyone know if they will fit?  Or have any experience with wheels and tyres of this size?

Any replies will be gratefully received. 

 

Thanks as always Mark

3

Hi Mark

I can’t answer the question with confidence and it may be that no-one else can either, hopefully wrong.

My suggestion is to try the wheels before you buy them. This may be logistically difficult but someone else locally may have similar.

I would expect the big brake setup to be too big for most 15 inch wheels.   

 

4

These are my ROH 15 x 7 et35 with Rainsport 3’s 195/50/15 fitted to my Mk 2.5 S-VT Sport (with big brakes)

 

Paul G

 

 

5

They look great.  Hopefully the ones I am after will fit.  My only worry now is your offset is 35 and the ones I like are 20

 

 

 

6

The problem is that every wheel has a different curvature between the hub of the wheel and the inside diameter of the wheel that fits over the brakes, this is where no one has explained how to test a wheel off the car.

Therefore at the moment apart from the wheels that have been detailed on this thread and OE Mazda wheels for these big brakes cars, you need as has been advised to physically get hold of a wheel and trial fit the wheel to your car.

No amount of posting online without detailing exactly the wheel you are wanting to fit will get over that and even then you would need to find someone who has used those exact wheels an a Big Brake Mk2.5.

7

Offset on a Mk2.5 should be 40, or thereabouts. I have Rota 15" 6.5 rims with offset of 38 - close enough. Tyres are Toyo T1R 195 55 R15 - slightly oversize but allows for wear. I don’t like stretched tires, so would avoid anything over 6.5 width. Brakes all round are clear, and have never suffered overheating or other problems.

Benefits - multiple, handling improved, so is ride, and 15" tires are cheaper than 16". Back end is now more stable, and tire noise slightly increased - it’s not a noisy tire, but I prefer tires to let me know when I’m approaching the limit going round corners. - The 16"s never did, just went. Also gained about 2.5 lbs per corner weight reduction, which improves unsprung weight and makes for better handling.

Some say the T1R is crap, - not in my book, I stake my life on them every time I drive. Never had a slide in the wet, and certainly no braking problems either.

IMHO you need to rethink your wheel selection. YMMV.

8

As has been said, it depends on the wheel. It is to do with the inner diameter. At 20 offset you are in a better position anyway as there is less inboard. 

If they are reverse fit, usually silly JDM stuff, which allows a deep, clean, dish, then they won’t fit. So if your valve is buried deep in the wheel then unlikely. 

7" width is absolutely fine for 195 50 15 and on a MK2 you will have no clearance issues, assuming they go over your brakes. 

They most likely will. 

9

                                   

Thanks for the reply.  You have really helped.  The wheels aren’t the silly jdm type they are Jag D Type ish replicas and the valves are not very deep at all.  I think I’m now going to bite the bullet and buy them as I haven’t seen any like them on an mx5.  Although I’m sure someone has done it before.  If they don’t fit I suppose I can always sell them on.

 

 

10

An interesting styling choice.