Wheel and drag radial questions

[68GMCCustom]

I'm getting ready to purchase some 10" wide 15" truck rallys and MT ET Drag Radials and wanted some feedback on the rear wheel backspacing and tire size. I'm unsure if I should get the rears in 4.5" backspace or 5" backspace? The wheels this truck had on when I bought it were 16's and it had the '68 Dana44 in....they rubbed the inside on turns, etc.
I was planning to buy 315 or so wide rear drag radials...but now see theres a TX drag racing series that limits rear size to a 275... or 28x10.5. The truck will get a different staggered combo later on in its life (when repainted)....like 17x8 fronts and 18x10 rears...which would probably take it up to a 30" rear. The truck does have a rear fuel tank to put more weight over the tires...but it doesn't seem to help.



So.....with a truck and the way this thing spins 275's on the street (1st can't grab and neither can 2nd until over 1/2 way thru its range) I'm afraid a 275/60-15 drag radial isn't going to be enough. I had planned on a 315/50-15 or even going up to a 30" tire with a 315/60-15 and lowering my rear gears from 3.73 to a 4.10 or even 4.56.
28" tall rear tires would avert the extra rear end expense tho.




So guys, help me out with your opinion.......4.5" or 5" b.s. for the 10" rears? Truck is a '68 short/step side and now has a '72 12 bolt.

And.......315 rears? or 275 rears to keep from being disqualified in some series? Or is this series a rare thing and just go with the biggest I can get to assure no traction issues? (315's?) And....stick with the 28"s? or make the move to 30"s now. I'm not even sure what class this thing would go under...other then just running a bracket series. On paper....truck should run 12's or so (or better).

[fair1138]

I had 10" wide rims, I think they were 6"bs. I went with MT 29x15.50-15 Sportsmen. The bed is cut to fit the tire, and the tire doesn't stick out.

Since then, Ive went with a 12" wide rim.

[68 C-10 KID]

10" wide you can go 5-6" BS but the 6" sits deep in the fender on a 10" wheel,
12" wide w/ a 7.5 back space works great.

[68GMCCustom]

I don't want to have to mod the bed until time for paint....so it would need to fit with the bed uncut.

[67_SS396]

The 275 class is real new around here. It makes for some great heads up racing and hope it sticks around. Some of them used to run King of the Hill and True 10.5. They are running low 5's on a 275 drag radial now and I remember when that was tough to do on a true 10.5 tire. If you get your suspension dialed in, you should be able to hook on a 275. For some even better heads up racing with no tire size requirement, check out TX Triple Threat. These are all the guys from KOTH after it disolved. A bunch of us will be headed to Redline the 20th of this month to watch some good heads up.

[Super73]

Playing with Drag radials for some time now, I would advise against a 315 on a 10" wheel. It seems most of the heavy hitting DR guys stretch the tire a bit to get the full contact patch down. A 275 would be right on a 10" and a 315 is right on a 12"..

You would be suprised what a sticky tire does for you. You would also be suprised how a 28" tall tire works compared to a 26" tall tire.

If you are going 10", go 275 in a 28".. It will work a lot better than a 275 26".
If you can go with a 12", 7.5" back space, get a 315/60/15 and put some more gear in it.

But even then, with enough motor, converter, gear, you can fry then even with the super tall 1st gear of a power glide. I have 315/60/15 MT DR's and I left a couple good 100' strappers on the way to the chassis guy today (haven't driven the truck in a couple months).

[Bad70sbchevy]

Back when my uncle had the truck, he used to run mid 12s on 275 Cordovans on a 15 inch rim (4.11 gears). Said the truck had no problem hooking up with the stock suspension and Koni adjustable shocks. Now as far as on the steet, not so much . Keep in mind this is NOT on a cheater slick.

[69trk]

Here's mine on a 8" rim with 275/28's. I tried a 295 and they looked way to tall on my truck. Plus i didn't want to change gear.. I had a set before but i couldn't get them to hook at all on the transbrake, but hooked pretty good footbreaking...