Page 1 of 1

flat head engines

Posted: Sun May 17, 2020 6:50 am
by toad
I was looking at some WW II stuff and I came across a Russian Blog with translations . In it he was praising the Jeep and the Studebaker trucks . He stated the village idiot could keep a jeep running. It seems the Studebaker three and two axle trucks with their 5 speed transmissions would go anywhere and the maintenance was fairly simple. One thing they liked about the Studebaker trucks was they had an " under valve " engine as opposed to the GMC "over valve" engine. In other words the Studebaker had a flat head engine. I remember that you could pull off the head with the engine still in the vehicle pull the valves insert new valves and lap then in. You could vary compression with a shim . He claimed it was easier to keep the Studebaker running with the crappy fuels they had. He showed a video of one running on wood gas.
I'm wondering the with improved fuels would a flat head be viable again?

Re: flat head engines

Posted: Sun May 17, 2020 1:22 pm
by MiddleAgedKen
I think the answer to your question depends on the purpose to which one wants to put it and the circumstances in which one intends to use it. For running just this side of forever in a maintenance-challenged environment where absolute performance is a secondary consideration: sure, why not? As an analogy, the old low-revving cast-iron marine diesels (Sabb, Lister, et al) are still completely viable in the right application.

For the quarter mile where the usual thing is to make a few dozen passes ( f/x: SUNDAY SUNDAY SUNDAAAAAAAY!!!!) and then rebuild in a machine shop (f/x: balanced! blueprinted! shot-peened! glass-beaded! magnafluxed! We need a bigger checkbook!), possibly not so much.

Re: flat head engines

Posted: Mon May 18, 2020 8:07 pm
by HTRN
Uh you do know that the all small engines are basically flatheads, right?

And theres at least two different aftermarket block manufacturers- Donovan makes aluminum Ford 4 cylinder blocks, and theres a manufacturer of cast iron v8 fords.

Re: flat head engines

Posted: Tue Jun 30, 2020 3:07 am
by Windy Wilson
I have long thought the flatheads were low-revving high torque, but it wouldn't be the first time I was completely misinformed.

Re: flat head engines

Posted: Tue Jun 30, 2020 11:37 am
by Old Grafton
Changing ("Shimming") head gaskets to change (lower) compression ratio and the reverse(milling or "shaving") made me think of my father's generation doing just that on various machines. A farm tractor had a shimmed head so it could run on "drip gas" collected from a gas well on the farm and an uncle had a hopped-up '50-something Mercury with shaved heads. I was the little kid who got to sit in the background and just listen, at least until the second or 3rd beers came out, and I got sent in to go to bed LOL

Re: flat head engines

Posted: Wed Jul 01, 2020 3:40 am
by HTRN
Windy Wilson wrote:
Tue Jun 30, 2020 3:07 am
I have long thought the flatheads were low-revving high torque, but it wouldn't be the first time I was completely misinformed.
That has nothing to do with the valve arrangement, and everything to do with bore/stroke ratio.

Re: flat head engines

Posted: Thu Jul 09, 2020 11:40 pm
by Windy Wilson
Thanks, HTRN.

Re: flat head engines

Posted: Fri Jul 10, 2020 4:14 pm
by blackeagle603
Flatheads tend to have a lower inherent rev limit so bore/stroke would tend to be design optimized toward developing torque at low end.