Ford 800

[pogfmk]

I'm overhauling my Ford 800 172 engine and am wondering if I could put LPG pistons in it and run it on premium gasoline for better performance?

 

[Hobo,NC]

No opinion other than a stock strong running 172 has a graces amount of power. There is always I want to : )

 

[michford]

I agree with Hobo. I cant think of a single instance after I rebuilt the engine in my 860 where I thought gee I wish I had more power. I added wheel weights to get the power I had to the ground usable. Are you building a tractor puller where you are looking to get every last bit of power out of the tractor?

 

[Wdj]

My 860 has more power than it can hold to the ground. Dont know if i was ever overhauled.

 

[showcrop]

The old four cylinder Fords had one of the highest power to weight ratios at the time. You can put a propane head on it, and put on a manifold and carburetor from an 801 to get more power.

 

[Btzj02]

There is a n 4 inch over bore kit available for these engines that come with thinner cylinder sleeves to be used in the OEM sleeved engine. Not sure if it will work for your 800 but, maybe.

 

[Keith Williams]

The old four cylinder Fords had one of the highest power to weight ratios at the time. You can put a propane head on it, and put on a manifold and carburetor from an 801 to get more power.

Great points Showcrop! They can also switch to the larger diameter exhaust pipes and muffler. Stuff from a 4 cylinder 4000 would also fit.
HTH
Keith

 

[Hobo,NC]

I'm overhauling my Ford 800 172 engine and am wondering if I could put LPG pistons in it and run it on premium gasoline for better performance?

What's the difference in the pistons ?

 

[Andy Wickiser]

What's the difference in the pistons ?

The Ford Parts manual shows pistons are the same for gas and LPG, see #30.

 

[Btzj02]

What's the difference in the pistons ?

The original pistons are 3.9 inch and the overbore kit pistons are 4.0 inches. Note that the sleeves are much thinner and prone to breaking during installation. .100" larger in the overbore kit.

 

[TomIn]

The original pistons are 3.9 inch and the overbore kit pistons are 4.0 inches. Note that the sleeves are much thinner and prone to breaking during installation. .100" larger in the overbore kit.

A post on this site a couple of years ago had an interesting discussion with various folks saying that both the pistons and heads were the same for gas and propane engines. Nobody seemed to dispute the propane engine had higher compression ratio.

https://forums.yesterdaystractors.com/threads/172-propane-head.1629181/

 

[Destroked 450]

As fast as dads 850 drank gas when working it hard I’d hate to have to feed it premium fuel
It had plenty of hp for its size with stock engine

 

[TomIn]

As fast as dads 850 drank gas when working it hard I’d hate to have to feed it premium fuel
It had plenty of hp for its size with stock engine

I'm just a geezer in the peanut gallery. The Ford 800 series engines were had rather low compression ratios (compared to modern automobiles.) A search showed a website which may or may not be accurate.

What Are the Specifications for an 801 Ford Tractor?

The Ford 801 Tractor is powered by a four-cylinder, liquid cooled engine that produces a power take off rating of 44 horsepower, and an overall horsepower rating of 67.8. This Ford motor supplies power to the wheels through a “Select O Speed” transmission consisting of eight forward speeds and...

www.reference.com

The site says

Looking for a compression ratio/octane requirements chart, about all I could find is

This suggests that modifying the engine may not require the use of premium fuel. Some articles suggest that compression ratio is not the only factor in determining octane requirements.

 

[johnnmr]

So what's the goal?

Researching 800s and 801s when I got into my 861 it was a noticeable pattern that back in the day guys liked their new 801s well enough but the extra power came in at the very top of the rpm band which wasn't worth the extra fuel used.

Switching my 861 back from a poorly done propane conversion I made sure I had the "big" air filter, manifold, carburetor, exhaust, AND gas tank($$$) the 801s would have had from the factory. I'd bet you would have to have those things too so your high performance build can breathe.