308 wheels

It may be easier if you list his top 3 or 4 choices

 

Superformance UK

 

What size are the original wheels?

 

Small LOL!! Jk Sorry

 

I replace the originals (Campagnolo 14") by a United Kindom reproduction on 16" .The main reason was the originals are made from Magnesium and after 40 years are not safe for use at high speeds... The reproduction are Aluminium Alloy.
See pictures attached.

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Where did this bit of wisdom come from?
And if you are very concerned, have them checked. I hear x-ray and other methods exist to check structural integrity.

 

I restored my original Cromodora high magnesium content (40% I think) wheels and the castings are quite porous with oxidation starting in the inclusions. Magnesium is prone to hydrogen embrittlement. A friend had a classic minilite break a lip for no reason. I would never drive hard on the originals.

 

The superformance ones are ok but heavy compared to the original magnesium wheels. The rear offsets are also not the same as standard. Exceptionally good value though and I have two sets one for the GTS and one for the GT4.

I did wonder before if possible to offset the extra weight with lighter brake rotors (whilst continuing to use standard callipers). Anyone have any experience of that?

 

There's two kinds of weight. Just the pure gravitational weight affects suspension responses, and lighter brake components could offset this. The other weight is rotational weight. The issue here is all pounds are not created equal. Those spinny bits closer in to the spindle matter less than the spinny bits way out at the tire tread. Shaving rotational weight affects acceleration and stopping responses. I'm not going to do the math but shopping for lighter tires probably will do more than drilling disks, aluminum hats, etc.

 

Wheels are personal choice.

328 wheels used to be a cheap upgrade for 308s.
Personally, I liked using 575 front wheels w staggered tires on my old 328.

 

Is this true? Are there any examples of the wheels failing at higher speeds? I am not aware of any.

 

Yes, Google it. But everything I found is about actual magnesium wheels and our wheels are aluminum-magnesium alloy and that's just a different beast, it's not as prone to issues. No interesting failures on the alloy wheels that I found.

But in the vintage motorcycle racing community mag wheels must be x-rayed regularly to be used on track. This is because there have been failures. But these are 1960s - 1970s era wheels and actual racing wheels. The industry moved to alloys after that. I'd bet you couldn't buy actual new magnesium wheels for any ground vehicle right now even if you really wanted to.

 

Brian is correct. Ferrari themselves a varied the magnesium content and found that a frighteningly high failure rate prompting the replacement of the majority of their mid 90s era magnesium wheels with aluminum substitutes.

The wheels would become porous and leak air overtime, then literally fall part under stress. From memory this was most pronounced in 512M and early 550 wheels

 

I had a friend that had a rear 14” wheel fail at speed on in the early 80’s while driving his 77 308 on a long road trip from Edmonton to Monterey. The inside ‘barrel’ portion split from the rest.

It’s now a trophy we use for racing competitions and goes back and forth.