MG Sports Cars

Hi everyone,
I have a '78 Midget with a ~175hp Mazda 13B. What would be the best upgrade option for me concerning the wheels and tires. I'd rather not do any body work. My car has the square arches.14" with Minilites looks good, but tire selection is pretty limited.

Graham, the options are very limited if you don't want to do any body work. Are you changing the rear axle? That could open up a bit of room but very little can be gained. Those rear wheel wells are just tight for anything more than about a 175 series tire. You might squeeze in a 185 on a 13" rim but you'd probably have to at least trim the inside flange on the rear fenders. For that much power I'd seriously consider doing the necessary body work to fit in more rubber, you'll need it if you drive even half way quickly.
Sticking with the stock body and rear axle width then I'd suggest sticking with a 13" rim, probalby in a 5.5 " width and a 175 series tire. That appears to be the combination used on Aaron Couper's car with the Jag 6. [www.britishv8.org] That's the only conversion I know of that isn't either a RWA body or had the rear wheel wells altered.

Thanks for the info. If I converted to RWA what options would that open up? I'm keeping the rear end for now. I plan on replacing the halfshafts with some stronger frontline units.



Edited 1 time(s). Last edit at 02/08/2010 11:49AM by Argatoga.

Graham, simply converting to a stock RWA rear quarter panel will allow you to go up to a 205 50 R 13 on a 6 " wide wheel with minimal rubbing only on full suspension compression, adding flares will open up the possibilities to almsot anything depending on how large you want to go. I added about 1" of flare to my RWA in the rear and still run my 205s on 7" wheels. [www.britishv8.org] That seems to be quite enough rubber for me, but you might want to go larger or a larger diameter wheel. Brian Kraus went with 15" wheels and some 225s on his car but used larger flares from Spridgetech. [www.britishv8.org]
As far as the rear axle goes, it's not only the strength issue to deal with but the lack of alternate ratios that is a limiting factor for the Spridget axle. With the higher rpm potential of the rotary the 3.90 gears should work out fine, but for my V6 I needed to get up into the 3.4:1 range for a comfortble cruising rpm range. Brian runs a Mazda axle with 4.10 gears as I remember.