Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing 15 inch wheels

Hello all,
Does anybody know if you can retro fit 6.5 inch wide x 15 inch sport wire wheels to a new + 4 built with 6 inch wide wire wheels or are there gap problems ?

It all depends on how closely the wings were fitted when the car was built. There won't be clearance problems inside if you are using Morgan 6.5" wires but you may get some slight protrusion externally.

Thanks jay,
I suppose I would need to borrow one and see if it fits,
I like the look of 6.5" sports wires on the plus 4. !.

With the 6" wide 15" wheels and the 195 width tyres the car is almost over tyred. There does not seem to be much point in fitting wider tyres unless the engine power has been significantly increased; something really only possible on a new GDI engined Plus 4 by changing the engine.

Putting 6.5" wheels would probably mean changing to 205 width tyres. The result would be heavier steering and more grip which would make the car handle differently.

There are a lot of Plus 4 cars which have actually been specified with narrower 5" wheels and taller tyres. The look is more classic, the steering lighter, and the car handles exceptionally well.

Perhaps it is better to try to drive a couple of cars fitted with different wheels and tyres before you decide.

I agree, Peter. There's a (literally as well as figuratively) heavy price to pay here. The best setup I believe is just enough tyre so the driver can provoke breakaway when they desire, whilst not breaking away when one doesn't. For lightness of handling and nimble steering, the narrower the better.

For track use of course it's a different matter, one is prepared to make all sorts of compromises for ultimate grip, you need it when you are cornering on the limit on every single bend.

But for road use, 99.99% of all driving is well within the dynamic limits of the car, and so tyres can be selected to give good handling characteristics. I have an engine more powerful than most Plus 4s at 165bhp, and I love having my 165 section tyres. The car doesn't let go unless I deliberately want it to when I'm in hooligan mode, and of course it looks much more the part in a vintage-styled roadster in my view.

My car will have 195 70 15 tyres fitted to the 6" wheels, what size are your tyres peter , I can see the car in a recent photo you have posted .
Thanks
Alan.

I agree about tyre sizes. I've a set of Minilites on order and am dropping half an inch on width and dropping from 205/60/15 to 195/65/15 to try to improve the feel.

Are your minilites 6" ?

I should say I'm having 185 70 15 (not 195)

Yes...6"

Peter and Tim are spot on here.

Morgan wheel widths have increased over the years , and the handling is no longer optimal for the design of the chassis and suspension. You want to be able to drift a Morgan under control, preferably with all four wheels. As the contact patch increases so does the grip, so now it lets go at higher cornering forces (usually speed related) and you need much better car control in order to be able to tame it.

My 1950s +4 race car handled best on 165 x15 tyres (85 section?) and could be easily drifted under full control of the driver. Eventually I progressed to 6 inch Cobra wires and 185/60 x 15 "sticky" Yokohamas , the grip was much higher, but the breakaway speeds meant that catching it required a lot of skill (and probably not a little luck on occasions)

Tim is correct here, you want to be able to provoke breakaway , but you also want to be able to catch it easily with needing a change of underwear each time.

In the 60s, the widths were 4.5 and 5 inches, and the cars handled really well, mainly on bias ply tyres in those days. Once radial plies came along the width started to increase slowly but surely until we now have 6.5 inch and wider tyres to suit. Yes the grip is better , but for this to be optimal a much stiffer chassis is required, and this is outside the operating envelope of most trad Morgans.

I would go to 185 width and 70 profile maximum.

My +8 resides on factory alloys with 205/60 x 15 tyres, it tramlines everywhere, it can be a handful (especially in the wet) and it just feels over-tyred for the chassis. I would fit Avon CR6ZZ in 185/70 x 15 (if the price was more reasonable), but I have been informed that 185 section on 6.5 inch rims is too much of a stretch and not recommended.