'69 Coronet R/T Wheel Tire Combo

Racers,

I'm looking for some advice. I have a '69 Coronet R/T Dana 60 3.54, 502 stroker, 4 speed. Dyno'd at 513 HP and 600 lbs. best run last year was 12.8 @ 113 on street tires. I have 15x8 Cragar wheels in back. What is the largest drag radial I can squeeze in the wheel well on the 15x8s? Could I go with 15x10's with a larger tire and would it make much more of a difference?

Also, I was reading another post about a cal-trac combo. Since I was thinking about taking the stock leaf springs off and putting Super Stock springs on, would it make sense to get a cal-trac combo?

Thanks!

Jerry

I run 632HP/696TQ in a '69 roadrunner with Cal-trac's. They work excellent. No way I'd be able to crush it off the line with street tires, but it's pretty decent if I transition into the rpm's correctly. One thing I will mention about them, they do harsh up the ride quite a bit, being there's a preload on the springs. You can easily take the preload off and soften things up. Last time I did, any quick hefty RPM....it was like riding on a greased tornado.

tire size can really depend on wheel offset & backspacing,
I'd say a 275/60/15, check tire mfgr sites to see what the actual dimensions are,
they have rim recommendations too,
you can go wider & narrower it will change foot print some & effect sidewall too
on an 8" wheel is about the limit, should fit relatively easily,
without knowing rim spec.'s offset & backspacing...

possibly a 315/50/15 or 325/60/15 with the proper backspacing
will have a little more sidewall/more rollout
a slightly less footprint on an 8" rim,
if it was on a 9"-10" wide rim,
it would be a slightly wider girth/cross section,
less diameter/wider footprint & less sidewall...

there's more that one way to skin a cat

basically in the neighborhood 13" of girth {about 11-12" of tread}
& appr. 30" of diameter max
without modifying the wheel wells too much,
you may have to get rid of the wheel lip &
of course depending on what wheel offset & backspacing "you actually have"
a 10" wide wheel with a 5.5"-6" Backspacing possibly,
the larger the tire diameter will make a huge difference in wheel width & BS needs
better to check & make sure with the actual tire & rim combo sizes...

different brands of drag radials are different in actual sizes too
allot of variables, specifics, to say 100%

there's a good tool for tire fitment,
made by PERCEY for about $70 from Summit Racing,
it will show you where the tight areas will be,
the wheel well gets narrower as it goes up towards the top

No idea. For street, 225-70 R14's front, 295-50 R15's rear. Stock springs. 8 inch rear rims.

The thing is with the tires of today you dont need 14" tread tires to hook. Myself I run radial slicks on the street and track. My 63's wheelwells are all stock as is the leaf spring location as nothing is altered or moved and I run 9 x 30 Hoosier radial slicks. And on just superstock springs it hooks great most of the time. Good enough for a 1.50 sixty ft and to run 10.70's. And good drag radials hook as good as slicks do. With just an average suspension you should be able to hook on 28 x 9 tires but you can fit a little larger tire in there. You just dont need 14 x 32's on your car. Find a nice drag radial about 10" wide and around 26 to 28" tall depending on what gear you plan to keep in the car. My suspension is nothing fancy at all as its just Superstock springs and the longed MP drag shocks. No pinion snubber and stock suspension up front with the CE 90/10 shocks. If you fill the stock wheelwell with a drag radial tire that fits in there with a little room to spare you should be able to get your car to hook great. Ron

Thanks guys for the advice! Hopefully I will see some of you at Mopar Nats this year.