Max. Wheel size for a 1966 Chevrolet

Does anyone know what the max. wheel size and tire combo that will fit under a 66 with no rubbing? Sorry to ask so many questions but you guys are brilliant about everything van

depends on how high the springs are too!

M1D

Maybe I'm not too bright...Which is true, but I don't know how this works.

I DONT CARE ABOUT SPEEDO, I CARE ABOUT THE LARGEST TIRE THAT WILL FIT UNDER THE VAN.

ugh again. So, every 66 has different size springs? I'm a little confused. Every vehicle I ever saw had a max tire wheel size combo. I dont have any friends with older cars or trucks so I can't just borrow a set. And, I would hate to get the wrong size and have them not work.

I read about that and according to Cragar, it doesn't matter the brakes for their wheels.

Wow, that's tough. I did find a engine and tansmission solution however.

I'm putting a polished 350 TPI in her along with a polished 200r trans.

I have 275/60/15 tires on 15x10 wheels on mine in the back and the tires don't rub when the van is fully loaded. i believe its a 28" tall tire. if you really want a fat-tired van that looks "right", you need to go with 295/50/15 tires on 15x8 rims with about 3-5" of backspace depending on how far you want the tires to stick out the sides. measure first though, don't take this as gospel.

maybe 205/70/15 on the front on 15x6" wheels.

The key to getting it to look "right" is to play with different profile sizes until you find a set that will have the same overall outside diameter or as close as possible, but never get front tires that are bigger diameter than the rear, that always looks wrong and is quite noticeable even with small differences.

-Tim

You want an easy answer. There is none, for the following reasons.

Stock, they had different springs, which means different ride height and different loaded ride height.
These were commercial vehicles built in the 60s. Tolerances when they were welded and assembled were not tight, so what may fit one one van or even on the left side may not fit on another or the right side!
All of them were built 40+ years ago and have had modifications, damage, fixes, and wear. What worked at the dealership may not now.

This means that you have to find a wheel/tire combo that fits YOUR van now.
It also means that you have to consider what your intended use is. The owner that has no interior and drives nice and easy to a cruise night can have the rubber closer to the sheetmetal than the owner that has a full interior, often loads a bunch of stuff inside and is driving it in gymkanas or across country.

You also have to chose if you want the wheel/tire combo to fit inside the stock wheelwells, if a little trimming is acceptable or if you want it sticking out past the sheetmetal. You can tuck a larger diameter tire inside, but it won't be as wide. If you extend out past the sheetmetal, you can go wider, but the diameter must be smaller, since normal suspension movement means the tire will move up toward the fender.
You can load something heavy (sacks of sand or gravel, a couple friends) on each corner to see what normal weight shift and loads do to clearance.

You can use the site listed to get a very good idea of what will fit after you have made measurements. I'd suggest that once you have selected a size that you think will work, try to find a friend with that combo to borrow and try, or go to a wrecking yard and buy one (usually under 50 bucks).
Tire stores used to be very helpful with this sort of thing, but the Explorer/Firestone thing has caused most chain stores to pull back on what they will even sell to the public. Try to find a smaller store and see if they have some stuff already mounted. You can also see if they are willing to pull one wheel, block up the van at normal height and roll tires up and be able to see if they fit. You have to be careful of offset when going this, most wheels only have very limited offset choices, if any. Again, if they have a used wheel and tire that works for you, go ahead and buy it. It can be your spare.

The front should always be the same or smaller. You have to check for clearance not only straight ahead, but through the full turning radius too and with a load. This is where the sacks of sand help. If you plan on a big offset, this will move the center of the wheel out and cause more clearance issues. It will also make the steering harder at low speed.
Your best bet for now is to grab as many pictures as you can of similar vans, and look at what works for you and what doesn't. Print out the good ones to take with you to the tire store. While they won't be able to read the sidewall size, they will have a good idea what you want (picture=1000 words).

One last thing, since you want the biggest possible wheel/tire combo, you will be very close to rubbing/touching. Take it easy and work up to faster cornering and braking speeds. Do not expect the tire store to do minor bodywork to clear, or to keep swapping out tires, especially if damaged! This is your project, take ownership and make it work!


I love this picture! I found it here. This guy is pushing harder than most of us would now. Notice the RF wheel is sized to fit inside the wheelwell, even at an angle and with a lot of weight compressing the suspension.
Notice the RR wheel is sticking out past the fender, but even with all the suspension compression is still not touching. Also notice the LR is off the ground! This is an extreme example, but shows that the clearance you measure when sitting changes when driving.

a 325-50-15 would look good on a 10in wheel.

Anyone know the backspacing/offset and the stud size for the original steel wheels?  I can't seem to find original wheels and hubcaps, so I'm trying to find a chevy steelies sized 14x6 or 15x7 that will also accomodate the S10 black hubcaps that debuted in 1982 (and used on various chevy modes through 1998~).  I found the photo below of someone using those caps.  Anyone know the owner??
Any help would be appreciated.

                                                               67 supervan...........The 14x6 has about a 4x1/2 inch back spaceing with a 5x4 3/4 bolt patern and a 7/16 thread  stud size the 65 and 66 Chevy truck has the same hub caps as the vans and will fit either 14 or 15 inch rims.!!!. 65 does not have the raised rib around the edge  66 does.....New they are aviable at lmc truck or any truck parts restoration place or you can find the caps on ebay under 66 chevy truck parts the rims arent so easy to find you can use any small bolt gm with stock steel rims S 10 pu or late 80s chevy impala will be the easyest to find most S10s are 15 inch witch will work with disk brakes and most styles dog dish hub caps.... The rims and hub caps on that green van are most likely off a 80s or 90s S10 PU.!!!!!........................   Good Luck....JOE...

235/60-15 front and 275/60-15 rear on 8" steels with 4" backspacing on a 68 G20.



Wheel well sizes are similar on 1st and 2nd gen, I like this combo as it fills the wheelwell nicely without rubbing.

Thanks guys, I appreciate it. I'll be putting up a want ad soon and will be listing s10 and g10 wheels, among other things.