Magnum 500 wheels

[Tony S]

My car came with the wire wheels and adaptors which were in the trunk. There were a set of fake wire wheels on the car. I don't like either and have always been partial to the Magnum 500s. I was contemplating the 17" but want to run whitewall tires and there are none that I can find for 17" tires. My question is What is the backspacing for the wheels and width. No one lists the Avanti application although I know its the same as FORD, AMC Chrysler and some others. I have the Turner conversion on the front. I have removed the coil spacer in the front so the front is slightly lower than stock for the 1976 year.

[Gunslinger]

For 17" whitewall tires, check with either Diamondback or Coker Tires...either should be able to help you out, but be prepared for sticker shock...they generally run about twice the price of the same tire in blackwall. You'll also be limited in width of the whitewall...most seem to be wide whites.

Basically, all you need to make sure of is any wheel you buy is what's called "standard offset" for an Avanti, though there can be some variations from one lot to another, but I believe the 17" Magnum 500's are one piece aluminum castings so that shouldn't be a problem. It seems to be the two piece welded wheels that variations might occur in.

One thing to be aware of is that's not at all uncommon for the coil springs on any Avanti to sag with age. Once that happens you run the risk of the tires rubbing on the opening lip of the front quarter panels on bumps...especially if you have wider than stock rims and wider tires than original (I found that out the hard way with a '63). With anything wider than a 6" rim on the front you run the risk of clearance issues with the frame or tie rod ends.

If you buy 17" rims, do a trial fit without a tire mounted and try it full turns lock to lock.

Unless you plan on some very spirited driving, I would personally stick with 15"x6" rims and appropriate sized tires. That combination will give you all the performance the chassis is capable of without breaking the bank. You can get new Magnum 500's in 15"x6" with white stripe tires for much, much less than the 17" Magnum 500's and 17" tires. I'm not saying not to do it as if that's what you want, go for it. I just don't believe it's cost effective...but that's just me. Some probably don't approve of some things I've done to my car. That's the beauty of what we do...we can personalize things and not worry about it.

I will say that I believe Magnum 500's are, at least to me...the best looking wheel overall for an Avanti. True wire-spoke wheels look magnificent, but their weight, complexity and high maintenance makes them a non-starter for me.

[Avanti83]

My car came with the wire wheels and adaptors which were in the trunk. There were a set of fake wire wheels on the car. I don't like either and have always been partial to the Magnum 500s. I was contemplating the 17" but want to run whitewall tires and there are none that I can find for 17" tires. My question is What is the backspacing for the wheels and width. No one lists the Avanti application although I know its the same as FORD, AMC Chrysler and some others. I have the Turner conversion on the front. I have removed the coil spacer in the front so the front is slightly lower than stock for the 1976 year.

On my 83, I'm running 15 X 8" Aluminum Rims with 3.5" BS on the front and 4.5" BS on the rear with excellent clearance with steelteck brakes on the front. On my 74 Avanti, I currently have the OEM Dunlop setup and will be running 17 X 8" Bullitt wheels from an early 2000 or so Mustang. They are about 4.25" BS on the rear and fit great but on the front they fit with about 1/4" clearance. A bit tight for my taste. I have a Turner setup ready to go on but my calculations show I will give up about 1/8" or so of clearance and bring the wheels almost to the tie rod. What I will do is run a 1" billet Aluminum spacer to set the wheels correctly in the wheel wells and clear all the suspension parts.

The 74 currently has 15 X 6" Magnum wheels that fit fine from the factory but my driving style needs more rubber and 8" wheels. I will get you the BS on my OEM Magnum wheels if you need them.

Bob

Edited July 26, 2012 by Avanti83

[Tony S]

The B/S on the original 15"wheels would be a great help. Thanks

[Gunslinger]

A 15"x6" Magnum 500 has a 4" backspace.

[Tony S]

Thanks Gunslinger. I am pretty sure I"m going to go with the 15 x6 magnum500 w/ white walls. It just seems right for the car.

[Gunslinger]

Just be ready for the possibility that there might be some slight interference with the calipers the Turner kit comes with. If that happens, a little judicious grinding on the high spot on the caliper will take care of that. It doesn't always happen...it seems to be a car by car thing.

With 15" you'll have a better choice of tires with white stripes, though even that is getting less available now.

[Tony S]

I sourced some of the parts for the conversion and am using the s 10 calipers which may be a better fit for rim clearance. I will definately check for rubbing.

[profaqualung]

Tony S-

Here is a little more info that may or may not help out.

Specialty Wheels makes a Magnum 500 rim in either 16 or 17 inch. I run the 16" rims - they fit perfectly over the Turner brake conversion, plus my front end has had one coil of spring cut out of it.

Tires -

Coker offers BFG in 215/65X16 narrow [2 1/4] white wall, and American Classic in a number of 16" sizes - narrow and wide whitewall.

Back to the rims - the Specialty rims are a high quality item - not spot welded like the 'Vintiques' rims. They are good to over 180 mph in case you choose to go that fast.

The rims in the pic on my signature photo are the 16" Specialtys painted to match.

PA

[Raymond Compton]

First, all of the above advice is excellent. Gunslinger makes many good points. He knows a lot about these cars.

I might be a bit late here but here are my thoughts on the subject of Magnum 500s. My '74 has 15x7 Magnum 500 rims. They were not original as the car was built with Borrani wire wheels but the Magnums have been on the car since at least 1975 and probably were obtained at the Avanti factory. At least the records I have show that the long time owner of the car regularly took the car to the factory for upgrades such as the Recaro seats and the "Blake" suspension mods.

The car has had the Turner brake conversion on since 1984. This last spring I replaced all of the brake parts, including slotted rotors and 4WD S-10 calipers. The 4WD calipers do not have the protrusions that need to be ground off and also position the flex hoses better. There are no clearance issues between the calipers and wheels or the calipers and frame.

I run 205/70R-15 tires. They are the current "cross" for the original F78s and look about right to me. They are basic Bridgestones with a narrow whitewall. You can get a more agressive stance with something like 225/60R-15. My car had Firestone Firehawk tires in this size when I bought it. Of course, your sidewall stripe choice is more limited as these types of tire seem to be raised white letter sidewall.

One point to ponder is the outside diameter of the tires you want to run, regardless of the wheel size. Unless you want to play around with speedometer gears, stick to 26"-26.5" diameter tires. Most of the on-line vendors seem to have this number in the specs for each size.

[scottschroeder]

This was all great info I just purchased an Avanti 2 , its a 1970. i also want to run the Magnum 500 wheels. Can the 15x7 wheels be run with the stock brakes and suspension with no rubbing issues?