Late engine parts into early Cub engine?

Tue Oct 01, 2013 7:31 pm

Does anyone have a simple summary of what late-model parts might be used in early engines, to raise HP? Or point me to an earlier thread?

Will late style pistons and cam swap in? Do late pistons require late connecting rods and crank? How about swapping in the Zenith carb? The late style governor? (higher rpm)
Or does one have to swap in an entire late-model engine?

Just curious, for after I get done with my present '53 cosmetic restoration, and get bored!

Re: Late engine parts into early Cub engine?

Tue Oct 01, 2013 7:42 pm

you need to change the carb and intake, cam, new style governor, pistons, to get the dull benefit . The pistons will fit the old rods. You may need to check for clearance at the head with the pop ups. Some have had trouble so they say. I have not had that problem.
Boss

Re: Late engine parts into early Cub engine?

Tue Oct 01, 2013 8:11 pm

:Dito: to what Boss said, except that on my 48 I did have to remove a very small amount of material from the combustion chamber to clear the pistons. I do not know if it was a difference in engine, or the fact the head had been planed a time or two, or if the pistons were slightly different than others.

Re: Late engine parts into early Cub engine?

Tue Oct 01, 2013 8:20 pm

In my experience, I found checking for clearance to be more accurate WITH a head gasket installed. Doesn't have to be a new gasket, just something to mimic the clearance when a new gasket is torqued down. I ended up removing material from a head that was not necessary as I was NOT checking clearance with a head gasket. Could have saved some improved compression and lots of time :headbang As for the rest of things, Boss has you covered. I went the extra $$ and had a cam reground beyond the late model grind--little booger will run like a bat out of ---- :!: :!:

Re: Late engine parts into early Cub engine?

Tue Oct 01, 2013 8:39 pm

Bill E Bob -

Where did you get a custom cam? What cam did you start with? What sort of lobe profile?

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 7:44 am

Used a std. 1964 cam and was reground to N Ford specs (profile they had on hand) gave just a bit of lift and woke it up a bit. Also used a late model larger manifold and opened the intake and exhaust ports on the block. Late model Zenith carb, pertronix ignition, 12v conversion and lightened late model governor weights. Went with the N Ford grind (diff between $60 and $240) rather than create a new one. Duration is not a factor until 3000+RPM and the C60 usually runs considerably lower than that. Clocked mine at 2600RPM governed.

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 8:06 am

wow, does all that extra power put stress on drive train? I'm picturing popping wheelies in the garden! Gotta say I wouldn't mind a little extra OOMPH sometimes though. Maybe make the mower work a little harder.

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 9:33 am

All that said, most of the difference you will notice after an overhaul is simply due to the fact that you have put parts back into spec (have original compression back, properly adjusted valves, etc.). The increment you get from upgrades will be minor. If you are replacing pistons anyway, upping the compression ratio is a cheap upgrade, might as well do it. Some of the other changes cost more for what you get and you may want to consult your pocketbook.

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 9:37 am

Bill E Bob -
Thanks for the info. Just one last question: who does cam grinding for agriculture engines? Doesn't sound like something an automotive machine shop would necessarily do. Can you recommend a specific shop?

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 9:41 am

Eoghan wrote:wow, does all that extra power put stress on drive train?
Hardly. IH used the same drive train parts in their standard Cub, 13 hp engine, and the high powered, 18 hp engine, numbered Cubs.

My opinion, current engine weak. Significant performance increase with a major overhaul, without engine modifications.

Edit: Agree with Jim. If you need more tractor capabilities than the Cub, you need a bigger tractor.
Last edited by Eugene on Wed Oct 02, 2013 9:47 am, edited 1 time in total.

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 9:44 am

Jim Becker -
The cost is not too major a concern, if it is in the hundred $$. After all, a compact utility tractor is over $10K. In any event, my cubbie is just something to have fun with. My serious yard work is done with my JD garden tractor.

Just as an aside, the Woods mowers that are used with Cubs certainly are not a modern design. I wonder what it would take to adapt a modern 3-blade deck to a Cub? Would need to fabricate lift arms and pulley drive, of course, and would need to be sure the drive ratio was correct.

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 9:52 am

RustyKnuckles wrote:Just as an aside, the Woods mowers that are used with Cubs certainly are not a modern design. I wonder what it would take to adapt a modern 3-blade deck to a Cub?
If you are looking for a lawn mower with 3 bladed deck. Take a look at the Numbered Cub Low-Boys. Fantastic mowing machines.

IH manufactured a number of different 3 bladed mower decks.

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 6:42 pm

RustyKnuckles wrote:Bill E Bob -
Thanks for the info. Just one last question: who does cam grinding for agriculture engines? Doesn't sound like something an automotive machine shop would necessarily do. Can you recommend a specific shop?

Well this one happened to be an engine rebuilder/machine shop. They handle everything from earth mover diesels to little 4 bangers like the C60. With a bit of searching, you should be able to find something similar in your area. As for my '64, it's a hobby tractor and was a nice diversion. I have Cadet rears on the front and dual turfs on the rear. Still waiting for paint, but fully functional and a fun toy. Will provide pics if you wish, sorry, no video capability.
BTW I sourced the pistons, valve parts and rings, they sourced the bearings.

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 8:05 pm

Just a quick question to expose my ignorance - the Woods 59" belly mower on my '59 has 3 blades - is there a difference in design, RPM's, ????? from the "modern design" ?? Dusty B

Re: Late engine parts into early Cub engine?

Wed Oct 02, 2013 8:53 pm

my IH C3 also has 3 blades