largest tire size

[65_LS1_T56]

I am in the process of minitubbing my 65 to fit a 295/35-18 under it. Frame mods (notched factory rails) are almost done and I was able to get 1.5" per side of additional clearance.
With a 20" wheel, you'll be into a larger OD tire, so be careful of the wheelhouses with a low ride height, they are not full width all the way to the top. They taper (radius) off and get narrower.

Aaron

[ttchevelle]

Its a bone stock Chevelle and I have 255's and it looks like I may be able to go a size or two bigger.
the wheel size is a 20x10.

[ttchevelle]

Im considering using the new nitto nt05r drag radial any fans/comments?

[ttchevelle]

Will a 265 fit in a stock wheel tub?

[65_LS1_T56]

I have a 275 on a 17x9 wheel just sitting under mine now, its real close to both sides, maybe 1/4 - 3/8" on each side of the tire. Certainly no room for suspension articulation. Looks like minitubbing for the wider tires is a must. Not sure about the 265.

[ttchevelle]

My wheel is a 20x10. I think the largest I can go is 265, due to the rim width. But I could be wrong. How wide in a standard measurement is a 265 & a 275.

[65_LS1_T56]

Check out this tire and wheel calculator:
http://www.rimsntires.com/specs.jsp
What's nice is that if you put in tire sizes, it recommends rim widths for that size of tire. You can also look at backspace and offset too. A 265 on a 10" rim is on the narrow side.
It's easy to figure a tires nominal width by its size. 265mm divided by 25.4mm/inch = size in inches. So, 265=10.433". However, this is not the actual overall width. Rim width and aspect ratio affect the actual. If you look on Nitto's site, I think they list actual cross section width when mounted on a particular rim. As the rim gets wider, so will the actual width (not one to one though).
Also, a 10" rim is actually wider than 10". The width is on the inside bead-to-bead dimension. So, I can't see a 10" rim with any size tire working on a 65 without some wheel tub mods.