20 inch wheels

[idaho norm]

I just aquired a wm300 for making firewood that can't be reached with my pickup without knocking off the shiny stuff. A guy told me that he once used twenty inch tires on his for off roading. ( he claimed he used the same engine . Can someone tell me if this could work with the limited hp I'm running. (251 cu in.) And what effect would it have on the drive train?
norm

[712edf]

Taller tires have the same effect as higher gears; higher top speed but less pulling power..That is fine for highway driving but maybe not so good for offroad, your engine has less leverage to work with..The plus I guess would be ground clearance....I'm not familiar enough with the engine & drivetrain combo you have to comment on if its a good idea.

[911response]

Idaho Norm I have 20" rims and 40" tires on my FFPW. It works fine. Send me your email I'll sent you a pic.

Jim

[KLEMM]

I have four 20" rims I am looking to sell. I am located in N. VA

[911response]

I have four 20" rims I am looking to sell. I am located in N. VA

Klemm, Do they fit the FFPW and how much you want and what kind of shape are thyey split rims?? my email is JCH8191191@msn.com.

Jim

[KLEMM]

Did you get my e-mail

[grover26]

20" wheels

Jim @ 911 response...What engine are you running, 230 C.I. or 251C.I.? Also, any H.P. modifications to the engine? Thanks

[911response]

230 all stock

[Clint Dixon]

I just aquired a wm300 for making firewood that can't be reached with my pickup without knocking off the shiny stuff. A guy told me that he once used twenty inch tires on his for off roading. ( he claimed he used the same engine . Can someone tell me if this could work with the limited hp I'm running. (251 cu in.) And what effect would it have on the drive train?
norm

I owned a 1948 B1PW for several years that had 8.25X20 tires and wheels. My Grandfather's cousin put these wheels on the truck back in the late 1950's. He used it every day until 1977 hauling bulldozer blades, dragline buckets, and other heavy loads. The wheels came off of an AA model Ford truck.

I found that, mathmatically, the 20-inch wheel combination created only a 10% increase in speed in any gear, or about half of what one would expect if switching from 5.83:1 to 4.89:1 gearing. This meant that the truck could be comfortably driven at 55 instead of topping out at 50. The 10% difference in lower gears, and especially in low range, was impossible to notice. Ground clearance was increased slightly. The truck also had the 230 engine replaced at one time with a 218. Even with this smaller engine, I noticed no lack of power compared to a Power-Wagon with a 230, 16-inch wheels, and 5.83:1 gearing.

There is a slight increase in unsprung weight by switching to 20-inch wheels, but it should not be any worse than adding the weight of a set of tire chains, and certainly not as bad as adding dual wheels to the rear. Just make sure your brakes are in perfect condition and your engine is healthy, and you should have no trouble.

[TK064]

I also have a set of the 20" wheels that were made from a 10bolt conversion that were sold on the PW forum a few years back. I recently switched to the combat wheels for my carryall rebuild with some military michelins. But the 20" rims are heavy duty and suit the PW well.

[grover26]

I also have a set of the 20" wheels that were made from a 10bolt conversion that were sold on the PW forum a few years back. I recently switched to the combat wheels for my carryall rebuild with some military michelins. But the 20" rims are heavy duty and suit the PW well.

Do you know what these wheels were originally from? I heard that certain 10 bolt wheels fit using every other lug with a few other modifications...possibly bolt hole and center hole diameter mods. Also, is 'drop' enough for wheels to be dualled -up?

[Jonas Smith]

This is a '51 PW I ran with 20" wheels dualed up...



They were modified 10 lug GMC wheels. 8.25-20 tires. It's more than just a matter of hogging out every other lug hole. It needs to be done in a vertical mill. I also changed to offset on the front wheels so they would track in the center of the rear duals. It would have been a better idea to make a set of wheel spacers to put the front wheels out farther instead of modifying the actual wheels.
Something like this- but on the front axle.


The dualie set up really took a lot of power from a tired 230 to get moving. The brakes were o.k., but if I really had it loaded down with wood they were inadequate and panic stops from speed would be out of the question.

[grover26]

Thanks for the info.

Do you know time-period wheels that are adaptable? (50's? 60's?) I was also considering increasing the off-set of the stock 6.5" PW wheels by relocating the centers so they could be dualled-up. That way I could retain the 9:00-16 tires. I understand that the 5.5" wheels have enough off-set to be dualled but must be used with no larger than 7:50 tires. I'm trying not to sacrifice too much power or 'speed' (Ha).

Were the wheels secured using the standard Budd inside/outside system, or some other means used?

Sorry for so many questions, just that I thought that dualling-up would be a bit more common with the 'PW set' and a bit easier to accomplish.

[Jonas Smith]

Yea, 50-60's trucks have them. Just go to a good junkyard and you will find them abundantly. As far as changing the offset on a set of wheels. It's a lot of work for a modest return. I have done it in the past with another truck, and I had to add a 5/8" spacer in between the duals to keep the tires from touching with any kind of a load.
trust me from expirence- if you want duals, go with the 20's and make a flange for the front. To change the offset, you have to drill out all the rivits, pound the outer to the right offset. re-weld it in place. wrap a piece of steel around the wheel to cover up the rivit holes, and then plug weld them on the inside, and gring everything down smooth. I hope you have a friend with a tire balencing machine so you can make sure everything is straight and true before you weld also. and when you do go with the duals, realise that your tail end is going to be 8' wide. Something to think about for a wood getting machine.

[grover26]

Thanks, again.... My primary consideration for modifying the existing 16" PW wheels, rather than going to the 20's, was to keep the tire diameter in a range that wouldn't bog down the engine, yet let me maintain the road speed I now have. I'll have to compare the diameter of the 9:00-16's with some 20" tires. Another was the necessity to 'find' six 20" wheels and tires, as I already have the necessary PW wheels. PLUS...I'm trying to keep this 'up-grade' from exceeding the purchase price of the vehicle.

Do you know if the 5.5" wide wheels with 7:50-16's will dual-up?, though I really don't want to give up any road speed.(again, I use that word loosely, LOL)