Wheel offset question

[Ian_S]

Hi everyone...new owner here, so don't tear into me for this one, I know there is a lot of info out there...

I've spent a few hours trawling throgh the various posts on here and NSXPrime and can see most of the answer, but really need some input before I push the button to buy some wheels.

I have a 91 NA1 NSX with stock suspension/ride height and am looking to fit some aftermarket wheels. Rears are fine, but the fronts come in 2 options:

17 x 8 et35
17 x 8 et47
I'd be fitting 215/40 tyres

From what I've read. et35 is the limit for rubbing and legal "flush fit" :cool::cool: and et47 would probably benefit from 5mm spacers. However, can anyone tell me if there is a preferred option to avoid rubbing or best fitment. I'd rather not fit spacers but don;t want to risk rubbing/MOT issues if et35 is too close to limit?

[RedCarsGoFaster]

I have used an offset visualiser before to compare different wheel sizes - have a look at this link and punch in the various dimensions you're playing with:

https://www.willtheyfit.com/


My NSX is currently for sale, and depending on the new owner's preferences I might wind up with a spare set of aftermarket wheels for sale that may interest you - in any case, there are some visual references for my NSX on aftermarket wheels at the link below:

http://www.nsxcb.co.uk/showthread.php?16169-1996-NSX-T-For-Sale

My wheel sizes are:

Front 17x7.5 ET38
Rear 18x9 ET42

I think I'd agree that 35 is pretty much the limit - my ET38s are about at the limit of what the front arches can cope with.

I seem to recall from my own time looking at wheels & spacers on Prime that front wheel spacers above a certain size require longer wheel studs, for which you have to remove the wheel hub from the upright. Fact-check that, but it might be something to look out for :)

[britlude]

stock '91 15 inch 6.5Jx15 ET55, the et35 rims have the inside rim 1mm different from the stock plane, so ALL the extra width is outboard so the outside rim 'face' will be 1.5 inches further out from what you have at the moment

the ET47 rims move the hub mounting face 14 mm further outboard on the wheel, so the rims both move inward 14mm, so the outer rim edge is just under an inch further out than stock...


8x17 et 35 will stick out 1.5 inches from what you already have,

8x17 et 47 will stick out about an inch further than stock

https://www.wheel-size.com/size/honda/nsx/1991/

(https://www.wheel-size.com/size/honda/nsx/1991/https://www.willtheyfit.com/index.php?)https://www.willtheyfit.com/index.php?width=205&aspect=50&diameter=15&wheelwidth=6.5&offset=55&width2=215&aspect2=40&wheel_size=17&wheel_width=8&offset2=35

https://www.willtheyfit.com/index.php?width=205&aspect=50&diameter=15&wheelwidth=6.5&offset=55&width2=215&aspect2=40&wheel_size=17&wheel_width=8&offset2=47

[britlude]

My wheel sizes are:

Front 17x7.5 ET38
Rear 18x9 ET42

I think I'd agree that 35 is pretty much the limit - my ET38s are about at the limit of what the front arches can cope with.



and thats with a 7.5 wide,..... OP is talking 8" on the front, another 1/2 inch on each side....

[Ian_S]

stock '91 15 inch 6.5Jx15 ET55, the et35 rims have the inside rim 1mm different from the stock plane, so ALL the extra width is outboard so the outside rim 'face' will be 1.5 inches further out from what you have at the moment

the ET47 rims move the hub mounting face 14 mm further outboard on the wheel, so the rims both move inward 14mm, so the outer rim edge is just under an inch further out than stock...


8x17 et 35 will stick out 1.5 inches from what you already have,

8x17 et 47 will stick out about an inch further than stock

https://www.wheel-size.com/size/honda/nsx/1991/

(https://www.wheel-size.com/size/honda/nsx/1991/https://www.willtheyfit.com/index.php?)

reposted below

[Ian_S]

Sorry all, just realised my calcultions were confused by a decimal point on my reply!! Schoolboy error.:laugh:

I should have explained :doh:, the car is on route from Japan and I'm looking to have new wheels with uk legal tyres awaiting arrival.
I'm confident the rolling diameter etc is all within acceptable tolerance, but I'm unsighted as to how much gap is available from standard wheel to arch outer edge, to fill. I know et47 works.

On et35, the full 39mm extra width is all on the outside of the hub - I just don't know how inset the originals are and therefore if the wheel face and tyre will be legally inside the arch edge at that level.

I just don't want to order et47 and then have to fit spacers!

Trouble is I know nobody locally with an NA1 NSX with standard wheels to check.

Thanks for the help/input

[Papalazarou]

Sorry all, just realised my calcultions were confused by a decimal point on my reply!! Schoolboy error.:laugh:

I should have explained :doh:, the car is on route from Japan and I'm looking to have new wheels with uk legal tyres awaiting arrival.
I'm confident the rolling diameter etc is all within acceptable tolerance, but I'm unsighted as to how much gap is available from standard wheel to arch outer edge, to fill. I know et47 works.

On et35, the full 39mm extra width is all on the outside of the hub - I just don't know how inset the originals are and therefore if the wheel face and tyre will be legally inside the arch edge at that level.

I just don't want to order et47 and then have to fit spacers!

Trouble is I know nobody locally with an NA1 NSX with standard wheels to check.

Thanks for the help/input

Hi Ian,

Where are you based? There should be someone in your area.

[Ian_S]

I'm in Newcastle upon Tyne.

[Papalazarou]

I'm in Newcastle upon Tyne.

Yep, that’s me out. I’m in Somerset :-) I think most owners live in the south-east. There are a handful of owners where I live.

[mutley]

Hi Ian,

Pity we didn't get a chance to meet at Silverstone, and nice to hear of another owner "up north". I don't really know much about wheel offsets ether, and as I have the wider front wings, I was asked if I wanted spacers fitted, but i'm not keen on that idea either.

Cheers
Jim

[Ian_S]

If you're in Lossiemouth Jim, you are WAY north. It's normally hard to explain how north Newcastle is...3 hour drive DOWN to Manchester��, but you're about 4-5 hours north of me.

I kept popping across to the NSX's, but needed to be on our stand GTRDC and after Sunday's wine tasting didn't get across to see sorepaws and Kaz!

[Kaz-kzukNA1]

For the 'looks', you really need to first decide on the exact tyre and then study the detailed spec.

Same tyre size such as 215/40/17 doesn’t mean the actual installed dimension among all tyre manufactures/models are the same.
You will see significant difference in appearance depending on the tyre make/model.

Also not sure you are aware of this but there is tiny offset between the R & L wing position against the centre line of the chassis.
You may not notice it with the OEM wheels but once you go for the aftermarket ones, you will see one side sticking out further than the other side.
So be aware if you are aiming for the 'hellaflush' looks.

Regarding the spacer, as long as it's from the well-known brand such as H&R, should be fine.
You may need longer wheel stud bolt.

Personally, for the offset, I won’t go anything beyond 40.
Otherwise, depending on how you setup the car, you will experience noticeable instability under hard braking, etc


Kaz

[Ian_S]

Thanks Kaz

I know the exact sizes and offsets I want/can get, but everything I'd read on here and NSXPrime** indicated 17x7.5 et35-42 for the front.

My option is 17x8 et35 or et 47. et35 will push the wheel out 39mm which is too much, based on info from sorepaws who indicated the arch had approx 32mm gap left to fill on standard. As a result ! was going to opt for et47 (moderate 27mm fill). Of course that puts me 11mm closer to the suspension strut, so if I have to I'd use 5mm spacers.

You mention not going above 40 - can I ask why that would impact braking stability, if it's no closer to caliper than standard wheels...or it more to do with balance of wheel "weight"?

Would you agree with my conclusions based on the comments above or do you think et35 would work?

Tyre wise it would be 225/40 to preserve rolling circumfrance.


**https://www.nsxprime.com/threads/wheel-fitments-for-nsx.143941/

[Ian_S]

Sorry, just realised I have a potentially better option, but didn't check as it was only 1/2" wider...would a better option be 17 x 7 et38?

Moderate 23mm poke out and under your 40 offset suggestion.

and I can stick to the more "normal" 215 tyre size?

[Papalazarou]

What wheels have you decided to get?

Cheers.

[Ian_S]

I'm looking at Work Emotion ZR10

[Papalazarou]

I'm looking at Work Emotion ZR10

They are really nice wheels. Not many seem to suit these cars. Personally I like OE wheels with a few exceptions. I also like the original offsets.
The American market seem to love massive wheels with flush fit. They can look good, but obviously destroys the original dynamics. It’s also a world of hell with no PAS.
I think there are some great repro options now. The mita type S wheels look good. As do their seven spoke and facelift. They are also well priced.
Volks always seem popular. The TE37’s have always been incredibly popular and you can kind of see why. The CE28N’s are also nice.
However, with the ever increasing prices of these cars, OE has become the baseline in many camps.
Funny to think that a set of fat fives were £300 a set 10-15 years ago. Even a set of 94-01 wheels were £400-600 for a non-refurbed set.
In hindsight I wish I’d bought them all up, as well as the all the OE radios that people were junking for terribly executed double din units. You know who you are with your hacked, badly fitting centre consoles and your checkered floor mats ������

[Ian_S]

The idea is to keep the OEM, get them refurbished if necessary and keep them in case I ever sell the car.

The ZR10 will hopefully look acceptable, not too blingy and if I opt for slightly smaller widths, keep the balance and handling acceptable on the road.

[mutley]

If you're in Lossiemouth Jim, you are WAY north. It's normally hard to explain how north Newcastle is...3 hour drive DOWN to Manchester��, but you're about 4-5 hours north of me.

I kept popping across to the NSX's, but needed to be on our stand GTRDC and after Sunday's wine tasting didn't get across to see sorepaws and Kaz!

Hi Ian,

yeah Lossiemouth is a bit extreme north, however, my car in in Edinburgh, so not quite as bad.

Cheers
Jim

[Senninha]

Hi Ian_S,

And welcome to the UK Forum …. A friendly bunch of owners, some you’ve already met virtually above … and many have an extraordinary hands-on knowledge of these wonderful cars.

You say your NSX is in transit and I think you said all OEM in terms of chassis/wheels/tyres. Therefore, it sounds as though you are changing purely for cosmetic reasons. From reading your posts it seems like this is a considered purchase with long term ownership in mind, which often turns out to be the case with the NSX.

Simply a suggestion for consideration. As your NSX will arrive stock, why not drive it stock for a few miles and discover what you do/dont like. For example, you may want more braking. This could be a change to later OEM calipers that will need a change of wheels, or aftermarket options that may determine a min 17” wheel all round. Suspension unless refreshed is going to be 32 years old. Whilst all may be well, you may wish to refresh and by doing so, look to change the ride hieght. This could also impact size/style of wheel.

The simply point is that I’ve seen many make changes before understanding their car and the changes they need or would like to make. Should you find yourself wanting to make other changes, you could possible need to change wheels again which could be an expensive change.

Whatever you do with your NSX, be sure to drive it and put many smiles into the NSX memory banks … rgds, Paul

[Ian_S]

Thanks everyone for input. Car and wheels now sorted and here...OEM wheels being refudrbished and will be held until I decide if I will resell this in a few years, after I've enjoyed the car!!

New car pic here (http://www.nsxcb.co.uk/showthread.php?16213-finally-arrived&p=132837#post132837)- http://www.nsxcb.co.uk/showthread.php?16213-finally-arrived&p=132837#post132837

[mutley]

Hi Ian,

I have now moved back to Edinburgh permanently. There is a Borders classic car show in a few months time (can't remember the exact date at the mo) that I am thinking of going to with my car if you are up for that?

Cheers
Jim

[Ian_S]

Thanks Paul

You echo my advice to Skyline buyers, I always tell them to think what they want to do with the car before throwing money at their cars. It's amazing how many people spend ££££'s on big power, for example, but don't upgrade brakes or suspension and wonder why they're no quicker on circuit.

The NSX is a bit different for me, I knew all I wanted to do was use & enjoy it for a few years and preserve the OEM wheels and looks of the car, hence the option to buy after market wheels but not "slam" it or fill the arches.

It's one of the first cars I've owned where I genuinely think there isn't much to improve the look of the OEM (apart from wheels ;)).

[Ian_S]

Hi Jim

It really depends on date and type of show...for my sins, I am heavily into the classic Skyline shows and take my KenMeri to most, so the NSX will get less of an airing at shows. Here's the car, in case you see me at any shows:

14889