Farmall Super H - cam upgrade?

I"ve got an original 1953 Farmall Super H.
I"m planning on a restoration soon.

Mainly I use it for running a 25,000 watt PTO generator.

I want to get a few more HP out of the tractor.
I"ve read that putting a cam from a 350 will help with the HP (presumably by opening the intake valves faster).

Can anybody tell me how much this will improve the HP?

I"m NOT interested in creating a "puller" out of it. Just need another 10HP or so.

I want it to look original on the outside if at all possible.

Your "just another ten hp or so" is pretty significant on an engine that only had 30 at the PTO to start with. It would be a lot easier and cheaper to buy an M and put it on the generator.

I don't know about the cam by itself. You'd want the 350 cam, 350 LP head, and 350 carb with some custom work. You'd want the biggest pistons you can get, and electronic ignition. You might also clean up the intake runners and match the manifold openings to the ports in the head.

If you have a DC generator with an inverter, you can increase the engine RPM.

Hate to burst your bubble but there's no way a different cam etc. will squeeze an additional 10 HP out of a 33 HP Super H. That's a whopping 30% increase over stock! And even if the SH engine COULD develop that much power at PTO RPM there's no way the cooling system would keep up.

If you truly need to 43 HP - and you will in order to spin a 25 KW generator at full load - you should be looking at a tractor the size of a Super M.

I've been using the tractor on the PTO generator already. It barely can handle it.

It just needs a little more HP. I just threw 10 HP out there.

Why do you think it won't cool it?
I can't remember if it has a water pump or not.

Id appreciate it if you could explain why I need the extra 350 parts. Don't expect me to understand your reasoning.

Why electronic ignition? It runs fine.

"clean up the intake runners and match the manifold openings to the ports in the head"

I have no idea what an "intake runner" even is.

With a 3.5 overbore kit, firecrater pistons,,, use a H gas head,, casting number 8043DC, you will hit your 43hp goal once its dialed in. You need 165 psi of cyl pressure to get you in the to the low 40's in HP. Chad

PS leave the cam alone in the Super H unless it shows extreme wear. JMHO

You're wanting quite a bit of extra power from that engine. To do that, you will need to get more fuel into the engine and you will need to get it burned efficiently. The "extra" parts will help you get there.

The 350 cam gives you a little higher lift and a little longer duration. The LP head has smaller combustion chambers for higher compression. There are tubes cast into the head called "runners" to take the air-fuel mixture to the valves and from there into the cylinder. Cleaning up those runners, and matching the manifold ends to the head ports gets you better air-fuel mixture flow.

With more air-fuel mixture under higher compression you could benefit from a hotter spark. That's how electronic ignition could help.

This project will not really be cheap, which is why a "worker" Farmall M might be a better choice for that generator. It came with the extra ten hp you want built in.

Listen to ChadS I've heard and seen his H and he knows how to get the power out of them. Cooling won't be an issue until quite a bit more power. 45-50 horse is possible if ya listen to the above info. 10 horse is hard by just putting in a cam, or messing the carb. Some real work is needed. By the way, an intake runner is the physical path through the intake and head. It is where the air and fuel flow to get into the engine. Remember there is no dumb question, only dumb people who dont ask, (and occasionally dumb people who don't know but just like to talk like they do). Good luck. E-mail me if ya got any more questions.

Red Mist,

Just because I hadn't heard the term "intake runner" before doesn't mean I need help.

I've re-build several tractors myself from ground up with excellent results, including the engine.

usetabesteve did an awesome job explaining what he meant.

Your comment is completely useless, next time don't even bother.

If they did change the cam lobe profile when they built the Super H from the H,,,,

I would imagine that they would have done the same change they made to the cams they built for the SMTA, possibly the 54 models,,

Possibly stage 2 Super M's, 400 and 450, and if it had a left handed camshaft nut for ID purposes,,,

Anyways,,, On the changes they made to those cams,, they slowed the intake lobe timing down
Almost overlapping the exhaust,,, but it built a condition in the cyl head in the intake ports, and also inside the cyl,,,

The valve stayed clesed long enough for the piston to start its downward travel to draw in the charge,,, Builds more vaccum inside the cyl when the intake valve openes,, Well it gets a little extra breath in,,,, stuffs more air in the cyl,,,

Ive had M cams read, and cams taken from original 450, and a SMTA that threw the cam gear and trashed the keyway and needed replaced,,,, and compared the two results on paper,,,, Even the new reproduction M-450 cams sold today are the same spec I found from the original 450 camshaft.

anyays again,,, if they changed the profile thats what you would have seen,, starting with the Super H.

Ive never had the H, SH 300 or 350 cams read to know the exact specs,, ( I have a cam from each engine now,,, to read em and record) Also owning a 53 Super H, a 54 Super H, 40 H, and a 52 H, and a PTO dyno,,, and way too much time on my hands,,,, well sir,, a good Super H is no slouch.

Chad

Chad, Thanks for the details.

A few questions:

1) Does the 3.5 overbore kit require machining or just drop in new sleeves? Also where to buy the kit & pistons?

2) You said to use an H gas head casting number 8043DC. Why an H head? What makes this head different from what I've already got in the Super H?

3) Will my stock carburetor work? Hoping so.
Maybe bigger jetting inside?

4) So leave the cam alone? I thought it might be good to get the intake valves to open earlier...

5) I would like to leave it 6 volt. Turns over fine for now. Do you think higher compression will force me to 12 volts?

Thanks for the info!

Mike

I doubt there is any need to convert to 12 volts. A Farmall M uses the same starter as the H, and the M will start just fine on 6 volts.

next time don't even bother.

Click to expand...

Okay.