Wheels and tires?

66 G10 bolt pattern? backspacing? I am having such a hard time figuring this out. I think the bolt pattern is 5 X 4.75. Is this correct?

What is the backspacing?

Are the original wheels 13, 14, or 15 inch?

Also, what are the original size tires in modern conversion? Like 205/75/15?

Please help!

Thanks. That was a big help.

Do you know what the backspacing is?

Back then, there was a standard offset. Pretty much centered to a bit in (positive offset). You could get reverse offset aftermarket, which would be negative (deep part to the outside).
http://www.discounttire.com/dtcs/infoWheelOffsets.dos
It was later that the wider tires and wheels came out. Then with all the FWD cars, the offset went a lot more positive (deeper inside) due to the suspension design. In most stock wheels, the offset is designed to limit scrub. Picture a line through the top to bottom of the tire, even with the mounting flange like shown at the site in the link. It will end up touching the ground somewhere along the tread touching the ground. Now picture another line drawn through the center of the kingpin (our vans), through the center of the upper and lower balljoints (RWD cars) or from the top of the McPherson strut through the lower balljoint (FWD cars). These should touch the ground at the same point as the tire line. When you turn the steering wheel, the effort should be fairly low since the tire is pivoting around the steering axis. Put your finger in the center of your palm and twist your hand.

If you put on a wheel/tire that has a lot of negative offset (a deep dish mag or chrome reverse wheel), the tire's pivot point is further outside than the steering axis. This means the whole tire is scrubbing across the ground in a larger arc. Put your finger at the base of your palm and twist your hand.
This is why the steering effort increases and the tires wear more.
While there is a perfect offest for each car, it is not something that must be strictly followed unless you are driving road courses and optimizing the entire vehicle.
On our vans, you are usually limited by the steering tie rod end to only so much of the wheel being inside. If you want to keep a low effort steering, this limits the amount outside too, so you end up with a fairly narrow wheel and tire. If you want a wider wheel and tire, you end up with that extra width to the outside (negative offset). Most people tend toward a wider wheel for looks too.

Thank you! I do want the low effort steering. I actually like the look of the skinnier/smaller wheels and tires.

Would you say like a 7" wheel? I really have no idea what is considered narrow. What was the original size?

they had 13s and 14s, both probably 4.5 and 5 inches wide.
Some HD ones may have had 15s, again probably 5 inches wide.
Everything was pretty narrow in the early to mid 60s. Even race car tires were rarely more than 7 inches at the tread. A tire size like a 7.00x15 meant a 15 inch wheel and the thickest part of the tire (in the middle bulge) was 7 inches across. The aspect ratio on 50s and early 60s cars was ~80%, meaning the height was 80% of the width. The late 60s saw the wide oval and other "low profile" tires of a 70% aspect ratio. That was the HOT stuff! funny now with 20 inch wheels with 35 series tires!
Unless you are going to do a full stock restoration, you don't want a tall narrow bias ply tire. You don't have to get a 50 series tire either.

Thanks again.

I want to do a 14" wheel. Would you suggest a 7" wide wheel with like a 205/75/14 for the narrow (kind of original) look?

Just curious,what are on your van now? Oh,and welcome to the site.

Thanks for the warm welcome.

Some old S10 rims (or something similar) from the late 90's with huge balloon-looking tires. It's dreadful.

When I bought the van a few months ago it was apparent that it was used for utilitarian purposes. I just wanted a hobby. It has taken a lot of work thus far just to get it down to the base. A lot of 70's paneling and fiberglass insulation removal as well as wood flooring and linoleum. I'm pretty sure it was used as home at some point in time.

katiem wrote:Thanks again.

I want to do a 14" wheel. Would you suggest a 7" wide wheel with like a 205/75/14 for the narrow (kind of original) look?

Each tire size has a 'recommended' wheel size. The 205 may be a bit narrow for a 7 inch rim.
Most of the big chains will ONLY mount 'recommended' sizes. I'd suggest reading up a bit more, figuring out what wheels you want and talk to your local tire store to find out what they suggest. What works in Phoenix may not be the best choice for Seattle. They often have wheel/tire packages too. Check them out, but remember they are subject to internal company pressures to move certain brands or tires, and that comparison shopping can often lead to a better choice. A good shop will let you upgrade to a better tire for a few bucks.

This page ought to give you a lot more info.
http://www.tirerack.com/tires/tiretech/tiretech.jsp

One more thing, 14" tires are getting phased out. They are still available for now, but the choices are more limited. That may be a good thing for you, since it's easier to decide.

A somewhat typical backspacing on a 14 or 15" rim would be 3.5 or 3.75 inches, this could be a 6-7 inch wide rim like the old chevy rallye or the pontiac versions. these will work on the front okay without scrubbing, reverse dish on the front will give ya grief for clearances on the wheel well opening. There are alot of choices on tire sizes in the 6-7 " rim widths, what you need to know is the overall diameter you can get away with or want for looks, you probably can run from a 26" tall tire to a 28" no problem, beyond that the other guys will have to input here.

RodStRace wrote:they had 13s and 14s, both probably 4.5 and 5 inches wide.
Some HD ones may have had 15s, again probably 5 inches wide.

Rod: How tall do you think the tires were for the 14" wheels?

http://www.discounttire.com/dtcs/infoTireMath.dos
this might hep you out on some diminsions

The problem is that the site is asking me to input a tire dimension. I don't have a proper grasp on the topic to know what to put.

What would be the shortest tire you would put on a first generation?

I don't have a Chevy manual but I do have one for my Dodge. It has original sizes that you can use to find a modern equivalent. tire rack, discount tire and coker all have a way to find a modern size.
Coker shows a 1965 Chevy all models as 735-14 and 775 -14. No mention of rim width.
A modern replacement would be 195/75R14.
That's a pretty small, narrow tire. You can go to a store and see them in person. Tires have changed a lot, and more important, cars have changed. People don't understand that your van has manual drum brakes and will not go around corners quickly. Tires and wheels are one area where you can increase the handling, braking and ride of your van easily.
I would really suggest buying a manual for your van, I was a professional mechanic for over a decade, and I got a manual for mine.

I have a manual. Problem is, I wasn't a mechanic...

haha.

I am thinking about getting 14 X 5 inch wheels with 195/75R14 whitewalls. I hope they fit and look half decent. Thanks everyone for your help. I am still learning.

I'm not familiar enough with 60s GM manuals to say where the tire info would be.
See if there is a section called Specifications
There might also be tire info under a Tire or Suspension section.

Where are you purchasing 14X5 wheels?

Thanks.

Wheels from Wheel Vintiques.

If you can handle the slimey underbelly of car swap meets, junkyards and garage sales, you could probably find a set of those wheels very cheap or free. They are not a popular size, and unless someone is restoring a mid sizties chevy there is no market for them.
However, then you have to make sure they are straight, then clean and paint them or have them powdercoated. If this is farmed out to pros, you will have almost as much in them as new, so you probably are fine getting new.
I would suggest having the wheels spun on a balancer BEFORE the tires are mounted to make sure they are not bent or out of round.

Thanks for the advice. I appreciate it.

This is an example of Old Skool 14's, G-60s on the rear E-70's on the front. a close new tire size would be 245/60/14 and 215/65 or 70/14. if there is such an animal I'm not sure.

personally I wouldnt put anything narrower than a 205 on the front, 195's are for Yugos

Digz wrote:personally I wouldnt put anything narrower than a 205 on the front, 195's are for Yugos

I have to agree, but the OP said
"I actually like the look of the skinnier/smaller wheels and tires."
and that it currently has "Some old S10 rims (or something similar) from the late 90's with huge balloon-looking tires. It's dreadful."

Sounds like a fairly wide tire is NOT what is wanted. Skinny is okay, so long as you drive within the limits... I love this picture, someone posted it here.....

Yeah, I missed my target by not saying how tall the tires are or explaining how the sizes work, Mostly I was trying to give an example of 14" wheels, I'm sure Im going to be off target here some but,, The old G60's are about 28" tall, the E70's around 27". the 50- 60-65-70-75 numbers are reference to your sidewall hieght and over all tire diameter in what ever wheel size you choose. The 205-215-225-etc, the tread width and this will determine what width wheel you may want to run. Im running 215/65/15's on the front on a 7'wide rim, these are a little more than 26" tall. A 215/70 series would be alittle taller yet. Another factor is the load rating on smaller tires and the ride quality,( not sure if our leaf springs let us tell the difference) a little wider should ride a little better and up the load rating. Better?

Digz What are you running on your van? Bill