Cub pistons choices

[EFV]

Angle mill a head on 60 cubic inch12 hp flat head tractor engine? That’s a trick for old technology V8 performance cylinder heads. The “trick cards” some guys pull out of their deck on here is amazing.

Even or square milling can cause air flow loss on a flathead. More static compression and lose cylinder pressure.
It's not" old technology V8 " tricks,it's flathead garden tractor pulling . Angle milling helps if you can't change
combustion chamber shape because rules prohibit it. A 60 cubic inch engine making 12 hp isn't squeezing the mixture
very hard,hence the suggestion. A 185 Cub only has one more point of compression.
The rules here say to be kind. Please remember that in further posts. Better yet,offer useful information if what is
posted can be improved.

 

[Fritz Maurer]

Air flow loss ! An engine breathing through a carburetor with a venturi that most of your fingers won't fit through !

 

[rustred]

i dont think that is what he means. unless the air filter is plugged. pretty sure that's why ports get polished and lined up properly.

 

[Fritz Maurer]

If the ports were chrome plated, you can't get any meaningful flow through that stock carb. The pulling tractors hes referring to probably had 36mm Mikunis on them. Under those circumstances, porting and polishing has a lot more significance.

 

[used red MN]

The rules here say to be kind. Please remember that in further posts.

Okay, I apologize I threw the gauntlet at you. I just think it is curious how things go off the track here.

I will be used to cut the lawn with a 59" woods mower. Has anyone any advice on replacing the stock pistons with the domed aluminium ones? I has enought power as it is. I don't mind spending some money, but some Ebay parts may not be what I want.

correcting what is probably a misspelling “It has enough power now”
I changed the order in which he said things
“..Has anyone any advice on replacing the stock pistons with the domed aluminium ones? I don't mind spending some money, but some Ebay parts may not be what I want…”
It’s doesn’t sound to me like he wants to spends boat loads of money to get it to make more power. Rather he is concerned what quality of parts he will get by spending his money to purchase parts off eBay. Then from there a guy wants him to put a turbo on it. Then you suggest he take his head to some machine shop to get what will probably be an above average cost machine job because of the special set up. I agree with what Fritz is indicating. Somethings turn into a freak show on here.

 

[Fritz Maurer]

Just for the record, angle milling WAS a V8 trick.... long before garden tractor pulling had any real following.... there was a small-block Chevy head that was the subject of discussion.

Certain heads were thinner where the external head bolts were.... it was believed conventional milling weakened this rail too much.... thus the head was positioned to have the majority of the meat taken off the intake side of the head. ( Hot Rod, 1977 Engine Annual).

 

[used red MN]

Just for the record, angle milling WAS a V8 trick.... long before garden tractor pulling had any real following.... there was a small-block Chevy head that was the subject of discussion.

Certain heads were thinner where the external head bolts were.... it was believed conventional milling weakened this rail too much.... thus the head was positioned to have the majority of the meat taken off the intake side of the head. ( Hot Rod, 1977 Engine Annual).

Since this thread has turned into “for the sake of argument” HRM’s writers are going to have to come to a consensus. From what I remember from the past and confirmed in this linked HRM article angle milling at least as applied to small block Chevy was mainly done to raise compression and to improve on the efficiency of the wedge combustion chamber. Which required the greater amount of material to be removed on the exhaust side of the head. Maybe on some other brand it was the opposite.
SBC angle head milling by HRM

 

[560Dennis]

Here is a nice set of pistons at Bates Corp with link .

IH & Case IH Engine Parts | Bates Corporation

Engine parts for International Harvester and Case IH tractors. New, used, and rebuilt from Bates Corporation, family-owned since 1965.

www.batescorp.com

 

[used red MN]

Here is a nice set of pistons at Bates Corp with link .

???
Here’s a nice set of pistons and rings from Yesterday’s Tractor with a link for $246.00 vs $300. Add gaskets or some other $5 part and they will ship free. And they come from the folks that provide this wonderful discussion forum.
Farmall Cub STD pistons from YT

 

[Farmall M 248]

There is a set set of M and W pistons on eBay for a cub.

 

[47fivewindow]

???
Here’s a nice set of pistons and rings from Yesterday’s Tractor with a link for $246.00 vs $300. Add gaskets or some other $5 part and they will ship free. And they come from the folks that provide this wonderful discussion forum.
Farmall Cub STD pistons from YT

 

[47fivewindow]

Thanks to everyone. lf I wanted a lot more power I would buy a super A. The flat tops here are going to fit the bill just fine. I'll let you know how it runs in a week or so. On the other Cub forum the consenus was it was a bearly noticeable difference to change to the domed pistons. A fresh valve job and a little stiffer gov spring should do it. I have a tractor with a bush hog if things get out of hand. There is something about a sweet running Cub cutting the lawn that makes me happy.

 

[rustred]

Thanks to everyone. lf I wanted a lot more power I would buy a super A. The flat tops here are going to fit the bill just fine. I'll let you know how it runs in a week or so. On the other Cub forum the consenus was it was a bearly noticeable difference to change to the domed pistons. A fresh valve job and a little stiffer gov spring should do it. I have a tractor with a bush hog if things get out of hand. There is something about a sweet running Cub cutting the lawn that makes me happy.

your on track. the cub does what it was designed to do. baby tractor for baby job, the bigger the job the bigger the tractor, till you get to the super WD9.

 

[grandpa Love]

He answered your question on dist curves. Like he said you’ll need schooling. Lol.

Well .. when I grow up and stop working on the old offset farmalls I will get my schooling 🫩...... nothing he posted was of any value to a discussion about a cub. My goodness this whole thread has run off the rails,it is however very entertaining .

 

[grandpa Love]

Thanks to everyone. lf I wanted a lot more power I would buy a super A. The flat tops here are going to fit the bill just fine. I'll let you know how it runs in a week or so. On the other Cub forum the consenus was it was a bearly noticeable difference to change to the domed pistons. A fresh valve job and a little stiffer gov spring should do it. I have a tractor with a bush hog if things get out of hand. There is something about a sweet running Cub cutting the lawn that makes me happy.

I'm glad you were able to pick through the craziness here and find an answer . We love cutting grass with our '50 cub and 184 Lo-boy. Hard to beat a couple hours on a Cub!

 

[EFV]

If the ports were chrome plated, you can't get any meaningful flow through that stock carb. The pulling tractors hes referring to probably had 36mm Mikunis on them. Under those circumstances, porting and polishing has a lot more significance.

Pulling tractors I am referring to have K301 Kohlers. Stock class so piston,rod, cam,points and exhaust manifold
can be changed. 4K max rpm,grinding or polishing of ports or carb strictly verbotten. Fuel must pass test.
12HP factory rated engines are crowding 18HP with these rules. Laugh all you want,little gains add up.

 

[Fritz Maurer]

Pulling tractors I am referring to have K301 Kohlers. Stock class so piston,rod, cam,points and exhaust manifold
can be changed. 4K max rpm,grinding or polishing of ports or carb strictly verbotten. Fuel must pass test.
12HP factory rated engines are crowding 18HP with these rules. Laugh all you want,little gains add up.

You're talking modified engines, I am not. It is still laughable that a high-tech modification such as yours would have any meaningful impact on a C-60 with the stock induction.
You actually have airflow gains with a K301 because it has nearly twice the carburetor and half the displacement of a C-60.

 

[joeysmith]

My vote is shoehorn a Cummins in it

 

[47fivewindow]

My vote is shoehorn a Cummins in it

A few years ago there was someone here who put a Kubota engine in a Cub. Looked like factory made.

 

[Oregon Tractor Jack]

I had a Cub engine rebuilt last year and the engine kit came with Fire Crater type Al pistons. I was a little surprised at that.

OTJ