Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Surface finish on 1970s plus 8 alloy wheels

Dave, looked at the wheels on my 1979 Plus 8 and they are as rough as yours. Couldn’t get a picture , sorry
MM

Many thanks to all the folks that looked at their wheels. I don't dislike the rough finish - it's just another mark of character absent in so many modern things. I was just curious to see if I had a particularly bad set. And I've learnt quite a lot about alloy wheel technology: eg: lots of interesting info here:
Casting:
https://www.tirerack.com/upgrade-garage/how-are-wheels-constructed

https://www.xometry.com/resources/casting/low-pressure-casting/
Forging

I have a new unused one with tyre if anyone would like it.
P

FWIW, the Morgan Plus 8 rough original alloys were used from 1968 to 1977 and then Peter fit the Milraces a 14" wheel (with same overall wheel/tyre diameter as always). A higher tyre sidewall (often referred to as a "higher profile") provides a plusher, more comfortable and smoother ride assuming equivalent suspension setup and maintenance, a good thing to have with a vintage built car with minimal suspension.

In 1982, he switched back to the same-looking alloys, but these have the smooth finish we are used to. In 1996 (?) The wheels size changed in 1996 (?) to reflecting the developed world's odd affection for less air and more metal at the 4 corners. Not to begin a discussion but replacing air with metal on a vintage vehicle with minimal suspension provision doesn't seem logical. However Mark Aston correctly told me, as it was becoming more difficult to finding 15" tyres even 25 years ago..though this is not the case outside that world.

Lorne (who rides on 15" tyres..either 205 60R15 or the easier found 195 65 R15 which are, for me, virtually the same)

My 1980 +8 was originally on 14 inch rims, but switched to 15 inch in the mid 80s when I competed. Tyre options for 14 inch were poor. My 15inch are a smooth finish. I run 205/60 by 15 and Toyo Proxes. Must get the speedo recalibrated sometime!!

You (and Peter Morgan) have good taste in tyres, Stephen.

Your original 14" tyres were 195VR14s. a high performance tyre. I use 205 60R15s interchangeably with 195 65R15.Speedo difference is 1.2% which is much less than normal speedo accuracy unless you use a programmable one.The average speedo, all marques, are set to over calculate speed...3-10% according to evil AI. I can confirm that with all my cars. I also learned to use performance Rain tyres for the UK and performance Summer tyres for Canada. "All seasons" are too much of a compromise for me.

Your speedo difference between your original and current rim/tyres is only 2.9%. If accurate speedo is key to calculate fuel consumption, a programmable solution is wisest. Perhaps Speedy Cables https://www.speedycables.com/gallery/electronic-speedometer-with-mechanical-counters/ can manage it for you. Also, your fuel tank can be altered to make its level accurate. Forgive me. I consult/coach a few racing UK Plus 8ers. Great fun!! Which Series do you favour?

Morgan always shied away from changing the shape of the trad much. The overall diameter of trad rims and tyres stayed the same whatever rim they used, they merely matched the rims with a tyre profile to get to the same diameter. Logic suggested that smaller rims were wise. The developed world's fascination with low profile tyres is, from a point of view or comfort and comportment, inexplicable. Air makes a better adjustable cushion than metal..especially for a road going mogger like me. .

Lorne