Classic cars forum & vehicle restoration.

[Invicta]

Currently on my 1975 J26 Mitsubishi Jeep I have 5 stud 15" rims.

As I can't find a replacement 5 speed unit for my 4 speed gearbox I am considering increasing the wheel size\tyre profile to reduce engine load.

The current spec is
5 studs
Each stud 8 cm apart (across centres)
Central hole 15.5 cm dia.

Can anyoen suggest a simple solution as all the 16" steel rims I've seen don't fit this.

Thanks in advance
Bernard

[Penman]

Hi
Have you considered a higher profile tyre on the original rims?
A 1" larger rim only gives another pi x 1 ie. approx 3", on the rolling circumference, assuming the same profile, and I would have thought it would be possible to get that amount of increase with a deeper tyre, half inch deeper profile.

I take it you have already checked that there is sufficient clearance under the wings when on full lock and a heavy load and/or suspension compressed.

The speedo will need recalibrating/changing otherwise it may well be recording less than your actual road speed, which would be outside accepted tolerances.

Edited the distance increase (mixed up my equations for circumference Pi(D) and area (Pi Rsq)

[Invicta]

Penman
Thank you for your comments.

I've been told that there is a greater range of tyre profiles if I go up to 16"
I do some easy "Green Lanning" so want tread pattern as well as increase in size.
"Don't we all Vicar"!

This may otf course be snake oil but the people who have told me arn't tyre salesmen so I am inclined to believe them.

Any thoughts on this?

Bernard