I'm trying to learn more information about the American Racing "N" code magnesium 5 spoke gusseted wheels. My understanding is that they made them in 15x13.5" and 15x15" sizes. I'm curious if anyone knows any more information about these wheels? Why are they referred to as "N" codes? What were they originally designed for? Purpose of the gussets? (I'm assuming to stregthen them) Also, if anyone else on here has a pair of these RARE wheels, please feel free to post up photos of them here. If anyone has any old American Racing catalogs with photos and/or information on the these wheels I'd love to see that as well. Does anyone have any old photos of these particular wheels on a car??
I am no help with the history of that model wheel but I have to say they are “wheel porn”. Very unique and a great looking design.
Here's a few photos for you. One of my favorite wheels. Hardly ever see them. 30+ years ago walked by a set probably 5 times at the Monroe swap meet 350 bucks, right about the same time I had sold off a nice little collection of magnesium wheels and my Harley to help finance my new shop. Guy at the Estranged drags in Toutle had a set for sale year before last, $3500 if I remember correctly?
A recent thread was started by a new T-bucket owner asking what kind of tires he should buy. The T has a pair of these.
I don't recall any reference to an "N" code and I can't add much but I've been infatuated with these wheels since first seeing them in magazines as a teenager. I do know that in the late 60's/early 70's American was having problems with the narrower magnesium five spokes cracking in the TransAm cars so the 200S wheels were used.
And those cracked too so they went to MiniLites. I crewed on Titus' 001 GT350R at vintage races. I sprayed cleaner on the wheels and there were cracks around 3 of the spokes on one wheel and 2 on another. This was before American brought out the aluminum repops.
IN the early 90's , my brother in law picked up a set of 4 wheels and tires, from a race shop at the local track. They were said to be off a trans-am camaro. Rears are 15 x 15, with a 7.00x17.50 x 15 "Big Jeloney Firestones, Gusseted Magnesium Wheels; Fronts are 11" or 12", (guessing), wheels aith 6.00x 12.50 x15 Firestones, non Gusseted Magnesium. I've never seen a set like these, so don't have much info, but very interested in finding out anything.. He passed on last year, and now I'm helping his wife figure out what she has. Most of his parts, (he had a barn FULL of 36 - 40 Chev parts), went to other builders. I'll be posting a couple of cars, (36 Chev Master Deluxe sedan, 327/4sp; 40 Chev PU 427/400), once I take care of minor issues.
Me neither. I am looking at options for cleaning them up a bit, reading suggestions over on the HAMB Tech page started by Gonzo1717. Much reading to do...
Not off a TA car. They could run 10-12" width and all 4 had to be the same width. 16" was also the preferred GT1/TA diameter by then. Those tires are also 1960s maybe very early into the 70s type. I'm thinking CamAm series. Here is a Big Jelony that was cut for a sprint car - 1972 - https://www.electricalrebuilders.org/eren/archive/ere_2006/ere_11_06_shea_knoxville.pdf
As a buyer of vintage magnesium wheels, I'd rather you not mess with them at all. No cleaning other than removing the dust.
By the mid ‘70s they were using wheels of that size in IMSA but mainly slicks, could’ve been a wet. But as you say the tyre doesn’t really tie with the wheel size when it comes to dates.
When IMSA started SCCA changed their GT1/TA rules so the same car could run in either sanctioning body. GT1/TA had been using slicks ever since they became available. SCCA GT1 cars are built to the same specs as the TA series. GT1 was the club racers and TA the SCCA pro series. Many GT1 cars ran a local TA race or two the help build the fields at the big races. My vintage tube frame 1996 GT1 Mustang has 12x16 on all 4 corners.
@alchemy, @29Sleeper, thx for the input. I read through the recommendations elsewhere on this site regarding care/maintenance on magnesium wheels , DOV and Gibbs seem to be the ave. of choice. At this point, i'm leaning toward @alchemy's request not to mess with them at all. The fact that there is a complete 4 wheel set w/tires, and the wheels seem to have the original type gold centers, (probably not a common condition either), i'll wait. Might try to air them up a little, find out if the tubes will hold air, low pressure. But today's not the day to do anything but watch the rain come down.
Race tires = no tubes - they cause heat build up. They also don't have dress rubber on the sides you can see the cord pattern. They will leak out the sidewalls. We used to refer to our old race tires as GoodYear air filters. Those will be display only tires. It's hard to say what you should do with them. The magnesium wheels at that age are brittle and could crack/break just using enough force to get a tire off. If you take them off you can paint the inside with tire slime to help hold air. Also paint the wheel so air doesn't leak out any cracks or pores in the casting. Be careful airing them. They are old enough not to have the bead retaining bump that will help.
I found this illustration of the Howmet Turbine car from December '67, showing it with these wheels on the rear. The 1/25 MPC model of the car has these wheels on both the front and rear, so maybe the real car, when completed, ran them at all four corners?
@sleeper29, they do have tubes, although in 2 of them, the valve stem has slipped inside. I put 10 lbs of air into 2 of them, and the so appear to be holding air. Adds to the mystery.
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