I know "wider is better", but is the benefit more of a consistency and stability thing, or are there 60-ft improvements as well?

With 275/60R15 on the old car, I have these wheel width options:
- 8", which is what I ran before; the original M/T ET Street Radial seemed very sensitive to tire pressure and worked best at 17.5 psi for me
- 9", never tried, but would fit OK
- 10", never tried, but mocked it up and it's a tight squeeze on my car between limited leaf-spring clearance and slightly trimmed inner fender well lips

Thx

The radial racers run as wide of a wheel as possible. I've seen some stretch to 14"!

That said, we can run a pretty consistent 1.36-1.37 on an 8" wheel if the prep is good. I would like beadlocks to keep the tire from moving on the rim, but that's not in the budget.

At your level, I don't think you'll see a bit of difference w/ a wider wheel.
The wider wheel is supposed to be better...spreads the tire out for a fatter footprint.
I use a 295-65 on an 8" wheel and rarely had traction issues when my car was naturally aspirated running mid 9s and low 1.3 sixty foots.
I'd love to have beadlocks, but I use hi-tack to glue the beads.

At least a 10" wheel..Honestly wider than that is even better. I run a 13" wheel with a 10.5" tire

I run a 275 Pro on an 8" rim and have had no issues. Best 60ft has been a 1.410. If the track is prepped even a tiny amount it dead hooks every time, they will spin a little when the track gets totally ignored and I don't know that a wider rim would help that.

My buddy runs a best of an 8.24 in the quarter with 275's on an 8" wheel with rim screws and no bead locks.

I've used 8" 8 1/2"and 10". You get a better wear across face with wider tyre . Plus I have found I can use 1 - 1 & 1/2 lbs more air pressure with the wider rim . This is with 275s , 10.5 radials and Goodyear 9"radials

Tex

I would pick and use the widest rim you can for maximum traction, been thee done that years ago

Might want to experiment, if you have the wider rims available.
And/or consider what future pans might be.

I use a 12 inch wheel .
No screws or bead locks just high tack
Been 1,18 60ft

10 would be the best, but the 9 would work great also.

FWIW, I own a set of each size mentioned. The ET Street Radials on the 8" are ooooooold and serve no other purpose than keeping those wheels from scraping the ground. The 10" have an unused set of the older ET Street Radials mounted already, which is why I know they're a tight fit. I bought the 9" wheels a couple of years ago when I stumbled across them thinking they might come in handy for just this reason.

275/60R15 Nitto NT555R, the factory specs are: 7.5"-9.0", but the tire is actually measured on 8" rim, giving overall width of 11.10".

I take that to mean:
- I could run on a rim in that 7.5-9" range
- the specs as far as sidewall to sidewall distance (so that 11.1" measurement) are achived when mounted on 8" rim

As others have pointed out, a wider rim will put more of the thread on the pavement, so usually better for traction.

Mine are on an 8 inch M/T rim

Sounds like you could run 10" wheels with the unused tires as a start and then once you have some data on how those work either move those tires to the 9" wheels, or buy new tires for the 9" wheels and see how they compare?

Yep... pretty much how I thought about it, too

I tried several different size tires on my old pump gas Duster with both 10.0 and 12.0 inch wide rims, 315x60x15 M/T ET Street Radials, same size M/T ET Street bias ply's and 295x65x15 M/T ET Street radials later on the 10 inch rims only, the 12.0 inch wide rims worked better on the 3 different size tires I used them on

Are the wider rim advantages many mentioned here mainly in the 60ft or is there a benefit at higher speeds?

I have mine on 10" wheels.

i have run 8" factory ramcharger steel wheels with the 275-60's on my charger.
in all honesty, they should be on a 10" wheel.
now, i have 29.5 x 12.50 hoosiers on the same 8" wheels on the car, and they work with 15lbs pressure, but they flex too much on the street with that low of pressure.
i have a set of 11" steel wheels that have a boogered up bolt pattern in both centers, caused by running the nuts loose.
i have a set of centers ready to use as replacements, but i just haven't got the wheels in the lathe yet to start the repairs.
i have built wheels before [steel only], so this is no big deal for me.
i try to keep the radial and lateral runout to .010-.020 on each wheel, but will settle for .025-.030, then rotate the tire on the rim for the best runout possible.