Wheel change 16" to 15" what's best?

Wheels, Suspension, Brakes & Tyres questions and answers

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Basho
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Re: Wheel change 16" to 15" what's best?

Postby Basho » Tue Jan 24, 2012 4:51 pm

I changed fron stock 14 x 5.5 with new Achilles rubber running 30psi that came with the car to 15x7 6UlLs with 195x50x15 Simex rubber running 28psi , I picked up no wheel wieght atall in the change and the overall ride quality is better than the 14s in all respects.

But the suspension is still ordinary and wooden , I'm not complaining , it's 20 years old and most other cars suspension would be totaly fraked long before this.

I've had a drive in another members car (thanks again Mike) who has Yellow Speed coilovers fitted (7kg F 6kg R I think) and the difference is astounding in road feel and steering responsiveness.

Much as I am unwilling to comprimise origionality I have to face the fact that if I want my suspension to belong in the third millenium I'm going to have to drag it out of the second.

Or live with stock.

If you go to 15s you will have a wieght loss --maybe-- which is always good.

Your call. :lol:

FYI I have a 1992 no frills unmodded 80000ks NA6.

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Re: Wheel change 16" to 15" what's best?

Postby Silvia » Tue Jan 24, 2012 5:22 pm

Good stuff Al...
My NB8C is also unmodded ,with 80000 km too...but 10 years old instead of 20.
Some say that's only baby mileage...... :wink:
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Re: Wheel change 16" to 15" what's best?

Postby project.r.racing » Tue Jan 24, 2012 5:27 pm

just be careful with the 195/50R15 tyre size. most i have seen have a load rating for 82. the NB requires a load rating of 83.

205/50R15s normally have a 85 or 86 rating.

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Re: Wheel change 16" to 15" what's best?

Postby Charlie Brown » Tue Jan 24, 2012 6:11 pm

Silvia wrote:Good stuff Al...
My NB8C is also unmodded ,with 80000 km too...but 10 years old instead of 20.
Some say that's only baby mileage...... :wink:


Stand by my previous post. 80,000 kilometers and your shocks are probably down to 10% of their original efficiency. That, and old tyres, is your problem.
Baby mileage for sure but not for those shocks. :cry:
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Re: Wheel change 16" to 15" what's best?

Postby project.r.racing » Tue Jan 24, 2012 6:47 pm

i'd agree, but i'd say 70,000km for 10-20%, by 140,000km, rooted completely.

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Re: Wheel change 16" to 15" what's best?

Postby Silvia » Tue Jan 24, 2012 6:50 pm

Point taken CB and thanks......shocks will be checked, while I'm obviously working on the tyre issue . Leaning now towards retaining the quite pretty 16" stock wheels and getting the 205/50 Kumho 31. Yes they are 5mm too tall strictly speaking....just have to wear 'em down 2.5mm quickly :wink:
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Re: Wheel change 16" to 15" what's best?

Postby sailaholic » Tue Jan 24, 2012 11:14 pm

Test drive! That's the great thing about Mx5, some on has already done it

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Re: Wheel change 16" to 15" what's best?

Postby NitroDann » Tue Jan 24, 2012 11:27 pm

Just get some 15s and stop the thread.

As for stock suspension, im sure its fine.

The issue is that the car is light, so its unsprung ratio is poor compared to a tank (commodore etc).

I was driving a friends car the other day with brand new Tein Super Streets and thought it had flogged stock suspension.

man up.

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Re: Wheel change 16" to 15" what's best?

Postby Basho » Wed Jan 25, 2012 7:21 am

NitroDann wrote:Just get some 15s and stop the thread.
As for stock suspension, im sure its fine.
The issue is that the car is light, so its unsprung ratio is poor compared to a tank (commodore etc).
I was driving a friends car the other day with brand new Tein Super Streets and thought it had flogged stock suspension.
man up.
Dann


:lol: :beer:

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Re: Wheel change 16" to 15" what's best?

Postby Charlie Brown » Wed Jan 25, 2012 8:12 am

Basho wrote:
NitroDann wrote:Just get some 15s and stop the thread.
As for stock suspension, im sure its fine.
The issue is that the car is light, so its unsprung ratio is poor compared to a tank (commodore etc).
I was driving a friends car the other day with brand new Tein Super Streets and thought it had flogged stock suspension.
man up.
Dann


:lol: :beer:



He needs to check that the correct preload has been set on the springs. I know from personal experience.
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Re: Wheel change 16" to 15" what's best?

Postby NitroDann » Wed Jan 25, 2012 8:39 am

I meant that compared to a car with proper sports suspension, it was soft (yep, double meaning there).

I was surprised to find it had anything but stock, and stock is so much softer.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: Wheel change 16" to 15" what's best?

Postby Silvia » Wed Jan 25, 2012 11:09 am

I think at this point it would only be fair to remind NB owners with 16" wheels and 205/45 tyres that the advice to change to 15" wheels and 195/50 tyres is very doubtfull.

Those tyres are only just legal ,with a 15mm drop in diameter (576mm v's 591mm) over the 16" and a fairly big change in speedo reading. Yes they are $20 cheaper but you have to pay for the new 15" wheels of course.

The 205/50 15" is much closer to matching size @586mm dia. but costs 50% more @$120 :shock:

My thought from this research thread is to stay with the 16" wheels and get new 16" tyres. 45 series or 50 series tyres (say KU31's) both run about $105 on EBay.
(the 50 series is a little oversize - but a better option than going to 15" wheels if you want the extra compliancy of 50 series)
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Re: Wheel change 16" to 15" what's best?

Postby sailaholic » Wed Jan 25, 2012 12:12 pm

How are 205 50 that much more when they are 145 each fitted and balanced? (ku 31 in Brisbane as of TODAY)?

why make all of these long threads then ignore everything anyone says?

15" will get progressively cheaper a you get sticker tires.

Yes you need to pay for the rims, yes that takes a while to work off.



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Re: Wheel change 16

Postby hks_kansei » Wed Jan 25, 2012 12:35 pm

sailaholic wrote:Yes you need to pay for the rims, yes that takes a while to work off.



But remember the OP mentioned that he wanted the stock ones from an NB8A.

I've seen them go for as little as $150 for the set.
let's say $300 for a good clean set.

The 16s could be sold for at least that (to be honest, probably more)

End result is 15s for nearly nothing, or even make some extra cash.
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Re: Wheel change 16" to 15" what's best?

Postby Silvia » Wed Jan 25, 2012 12:47 pm

KU31 195/50 15 EBay $85 freight $15 fitting $15 = $115
$120 cheaper over 4 tyres. As said you wouldn't want those anyway...too small.
205's a better match but $120 each!
Better to stick to the 16" as said....

My decision IS based on the input here, naturally you have to base decisions on those.
Don't be angry if it isn't the same as your opinion....that's what forums are all about. :wink:

hks....I don't want to go to 15" with all the hassle, if there's no advantage, and I can't find any :lol:
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