Mopar Muscle Association UK

Hi all, I would like to replace the front tyres on the Dart due to cracks and perishing but I'm getting a bit lost on sizes and Bias/Radial etc.

The fronts are currently marked as 155 SR 15 RADIAL TUBELESS

The rears are Mickey Thompson Sportsman 31x18.5 - 15 LT which I believe are BIAS ply? Is this safe? Seems to have been OK for previous owners and my 5 meets at the end of last year.

Do I need to be looking at drag specific fronts? The colossal rears are staying until they wear out at the moment before I then consider slicks or not, for a replacement later on.

I guess while I'm at it, any thoughts on rears? I dont intend this to be a road car TBH

Cheers, James

Forgot to say,

the rears have tubes fitted and the wheels are drilled for screws. Not really in a position to replace the wheels and I guess tubeless doesn't work with drilled rims?

Legally you can have radials on the front and bias ply on the back if they are over 10" tread width, so that's ok. As long as you use a road tyre that is speed rated above your predicted MPH, that's fine. Race front tyres are more about light weight and minimum rolling resistance than anything else, they are of course suitable for high speed use as well. A 31"x 14" slick is as much tyre as you're ever likley to need. Rim screws and tubeless tyres is fine, the screw only just bites into the bead. The slicks will keep going flat though, the thin construction of them is not 100% airtight.

I thought if you run bias on one end and radial on the other the radial must be on the driving end.

Yes that is the case unless the rear tyres are over 10" wide and then you can have the radials on the front, it's in the Constructions & Use regs.

Sounds good to me.

Thanks, Blue. It was all getting a bit with conflicting views online etc.

It's my rear tyres that are most likely to improve my times (along with drivers skill but I'm working on that ) but for any Spring time shenanigans they still have plenty of life in them to practice on, that's how it is at the moment at least