Wheel Adapters
cast aluminum, especially if it's ADC12/A383 is quite brittle, with maybe 3% elongation at break, with a yield strength of about 22ksi/UTS of maybe 30KSI. 6061T6 is much tougher and more ductile with 17% elongation at break, 40KSI yield and 45KSI UTS. that's not opinion, that's fact. hit a pothole at 40MPH and see which one breaks first.
That may be, but
My opinion is this;
I grew up in the 60s and 70s, and most of us high-schoolers ran those, on our A-bodies, to get 15s on the backs of our street cars.
My Swinger was a DD, and in the 5 or more years I had it, she racked up a pretty good amount of miles; over two years worth still in high school.I drove that car everywhere, all the time.
By 75, that car was on it's Second engine, second or third set of Synchronizers, numerous second gears, three or more clutches, second rear end, second alternator, and second going on third starter.
When I sold that 70 Swinger 340/4-speed, in 75, they were still on there. and still with the slapper bars too.
But hallelujah, miracle of miracles, the adapters were surviving just fine.
And today
My ancient, refurbished, 15x10 kidney slots are doing just fine on the back of my 68 Barracuda. The 367 in it, easily having plus 50% more power than a 70 340, is still breaking 4-speeds and still breaking rear ends, But you know, those old used cast wheels I installed are still surviving, now on BBP axles..
And just so you know;
I've had several other cars that ran that style of adapter. If I had a dollar for every time somebody told me I couldn't or shouldn't do something, Ida had a fistful of dollars.
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In my first post, #5, I was not promoting those adapters, merely answering the OP's question,
In my second post, #10, I stated the truth, still promoting nothing.
In my third post,#13, I am still not promoting those adapters, rather I am stating the facts of my experiences. Facts/NOT opinions.
I got an idea
How about you doom and gloom anti-adapter theorists start another thread, entitled something like;
"what experiences have you street-guys had with these SEMA-approved adapters"
That may take your argument out of the realm of opinion and into reality. Until then, as far as I'm concerned, yur just blowing smoke.