Farmall super m oversized bore and turbo

Hey all, I?m restoring a farmall super m. Planning on putting
new sleeves and pistons in, 4 1/8? bore. Also when the
sleeves and pistons are in im planning on putting a keystone
turbo on. It says the turbo is rated for a stock motor. Was just
curious if anyone had emu experiences with the turbos on the
ms or oversized bores? Thanks

Go for it. The difference in displacement will be just fine. Remember it is a 3 main bearing engine. Twist it radically and it will not last. Jim

My 2 cents. You will be fighting knock at high boost. Premium gas, lower base compression, will help. Making it breathe easy is your friend.

How does one achieve a lower base compression? Also that is what I?m weird about. I do not want to throw a rod or do something the engine can not handle. It will not be meant for pulling i will use it for everyday farm work. Hauling wagons, manure spreader etc. but the specs on the keystone website state it will make it 80% more efficient with a stock engine and no engine modifications are required. Does putting in oversized rings and pistons make it more vulnerable blow up or bust?

(quoted from post at 03:53:57 02/15/18) How does one achieve a lower base compression? Also that is what I?m weird about. I do not want to throw a rod or do something the engine can not handle. It will not be meant for pulling i will use it for everyday farm work. Hauling wagons, manure spreader etc. but the specs on the keystone website state it will make it 80% more efficient with a stock engine and no engine modifications are required. Does putting in oversized rings and pistons make it more vulnerable blow up or bust?

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I do not know what my Wifes Grandfather did, but he put this kit on a Super M and blew the engine twice and another headgasket before pulling the turbo off. I know that the engine was rebuilt by a competent machine shop that builds pulling engines and it still blew. My wifes Grandpa just laughed to me and said that was a bad 15k decision. It sure sounded sweet and I also know he used it on a sileage blower, so it wasn't a parade only tractor.

I've heard of others liking the kit and there is a youtube video by a guy who hated it.

Good luck.

im just curious why put a turbo on for everyday farm work. can see going with the 4 1/8 pistons but turbo i cant see the practicality of it. these engines turn over at about 1650 rpm from factory and speeding them up for power i guess they wont last.

(reply to post at 20:25:49 02/14/18)

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Got a neighbor with a keystone
It is just fine
Runs around 75 hp with stock pistons
Works great

You can get 75 HP out of a super M with a 281 Kit and no turbo. That's rebuilding carb and dist to kit spec and LP manifold.

If you need more power you might be better trading m off for something newer and bigger, Turbo kit and overhaul will be expensive and turbo will not be as trouble free as you may think.

I don't know, bud. I never heard of putting turbos on emus, but hey, anything is possible.

They might need to wear compression underwear to stay in one piece. Jim

I would watch that you tube video, about a guy with his turbo experience on his 450 gas.I put a turbo on my 806 diesel, 49 years ago this summer, and it's worked well, but that's a entirely a different engine and fuel, and a 7 main bearing engine.

Sounds like you need a 756 diesel, 826, maybe 806 diesel. Putting big sleeves & pistons and a turbo on a 36 hp tractor and trying to farm with it at 75+ hp is just begging for problems.

So to clarify, I do not need the extra hp for the tractor. We have tractors up to 300hp. The thing is our family farm is case and internationals. Also we are big diesel fans (mud trucks, dozers, tractor trailers ect.) so the sound of turbos and blow offs in our family is like the sound of a v8 hemi to an old timer, we just love it. And since I?m in the process of restoring this super m I wanted to make it something you don?t see everyday. Something that other farmers will see and go ?hey check that out?. It won?t be pulling a disk or a plow because that?s what our big stuff is for, but at the same time it won?t just sit in a barn until pulling season comes around. Just a tractor for light duty farm work with that ?wow? factor, pulling hay wagons with round bales, maybe a spreader and bush hog. So it?s not like I will be red lining the thing every time I take it out.

Use premium fuel, retard max timing to about 18 degrees, and keep boost to 5 PSI and it will live. Just realize they are already at about the max for the bull gears and drive line. The 560 had real issues with final drive failure (M drive components in origin) when twisted with a 6 cyl. Jim

(quoted from post at 21:44:21 02/15/18) Sounds like you need a 756 diesel, 826, maybe 806 diesel. Putting big sleeves & pistons and a turbo on a 36 hp tractor and trying to farm with it at 75+ hp is just begging for problems.

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I believe the Super M was rated for 46hp stock.

I would suspect as long as you don't spin it over 1800RPMS it will last for the long haul.
Beyond that, as said, its a 3 main bearing engine. That means there isn't a lot of load bearing area to handle the stresses of that crank spinning over. The faster it spins, the harder it is on those bearings.
After some point you start to wear them out quick and then beyond that you could throw a rod.

I have frequently seen Farmall M engines in pulling that rev'd probably over 2200 RPMS but that's for a very short period of time and they don't farm with those tractors as they are pushing in excess of 350ci.

So in short, if you don't hold long term RPMS over 1800 itll probably last a long time, boost or not.

Increasing the bore to 4 1/8th brings that block to 281 cubes, same as a 450 and they were rated at 55 horses at standard rpms of 1450 full load and 1595 high idle. This was stressing the block the way it was with more than a few ending up with cracks in block right at the middle main bearing.

I have zero experience with a turbo charger on a gasoline engine and don't need any.

I rebuilt a 1951 M back in late 60's's with the help of our local IH dealer. We put the complete IH 281 cubic inch fire crater kit including carb and dist kit that came with overhaul kit. We turned it up to 1,800 RPM along with governor. They dynoed it at 75 HP.and we farmed with it until 2001( quit farming ) and sold it in 2010.The guy that bought it put new tires and fixed some leak and painted and is still using it.

You were REALLY lucky. the counter bore at the top of the bore the ring on the top outside of the sleeve sets in gets REAL close to breaking into the waterjacket with those larger diameter sleeves, Super M's even got thin in that area. M&W only made 4 inch bore sleeves/pistons for M & Super M's for that reason. The 4-1/8" bore sleeves/pistons was for 450 only. SM & 400 were 4 inch. Unless they were lying in their catalogs.

25% of your hp increase came from the added rpm, I've only ever heard of two M's breaking a crankshaft, neighbor's M that the machine shop screwed up and planed head 1/8 inch, .125", instead of .030 inch, ran about 2 years pulling M-sized equipment before it broke. And a guy on RPM says he broke one years ago. But heard of lots of M's cracking the main bearing webs in the block.

The pilot bearing in the transmission was too small in the M, hopped up M's pulling hard in 4th gear would pop the little stub end of the sliding gear shaft off and all kinds of carnage happened faster than you could grab the throttle or hit the clutch. IH almost doubled the size of that stub end in the Super M. Running in 2nd or 3rd was fine, That's why Dad put the Fast 4th kit in the '51 M out in the shop. He could plow 5 mph in 3rd.

IH noticed the inner rear axle bearings and diff carrier bearings started failing at a higher frequency when M went from 36 hp to 48 hp Super M, then 50 hp 400 and 55 hp 450. Same bearings that were changed in the 560 rebuilds. Wonder how long they would have lasted at 75 hp?

The M I had had a 264 block in it and the 281 fire crater kit dropped right in 264 block. When I rebuilt tractor we went through the transmission and that snub end had been repaired at sometime but didn't look good so i replaced that whole shaft with a new one.I had the throttle marked for 1650 RPM and the only time we would open it to full throttle was in a hard pull in field or was tractor pulling. Dad and I were the only ones that would use it. Didn't allow any hired help or family use it.