Building a farmall 350 motor on a budget

350H

New User
I have a 350 (c-175) motor I would like to build for a farmall h pulling tractor. What could I do to the motor for more power with a budget of $2500 to $3000 max?
 
4000-5500 weight class 3-3-1/2 mph transfer and dead weight pulls most of the assembly I will be doing myself.
 
Should be able to do a stroker crank maybe ? to ? inch. Use stock rods, custom pistons with your desired comp ratio. Pulling cam. As long as you can do all of the clearance work and assembly work yourself 3000 should be enough.
 
sorry if I ask dumb questions but this tractor stuff is all new to me. can I get the 3/4in stroke by just doing a off set grind on the crank and still use my stock rods?
 
As to your offset grind question, you will only get the amount of the offset for stroke increase. And that will not be enough. You will need 3/4 to 1 inch of stroke to make 5500 competitive. My last engine was 3.75 x 4.75 (210 cid) and I could handle 4500 in low. Made 65 hp at 10% over stock RPM. I did all the assembly and tuning my self and had ~$2100 in it in 1997 dollars. The good news for you is that there are multiple builders that make "kits" for the rotating assembly that are more affordable per cubic inch, I didn't have that option at the time. If you search the forum here, this topic has come up many times for this model of tractor. Lots of good advice to be found.
 
We had our 350 block bored to run 3 7/8 Oliver M&Ws in ours. The rods were machined to press fit the pins and we filled the block. We only ran in 3250 - 4000 but were successful at 3 1/2 mph. It's actually for sale here in central Mo. for around what you intend to spend. gm
 
I have a low low gear in an H also a O4 ring and
pinion and a set of 16x9x38 full cut Firestone?s that
may help you don?t need a big engine with that low
low gear.
 

Where you pull is a huge deciding factor. If your club rules limit speed to 3.5mph and actually measure speed, then you don't need to do much to an H to compete if its like where I am.
But then there are areas that would stop a stockish H far short in 5000lbs class. Generally speaking, a stockish H (overbore kit with high comp pistons, carb work, fine tuning) will do fine up to 5500 in stock, speed limit 3.5mph classes as you can pull in 1st with 10% over speed will get you close to 3.5mph.

If there is no speed limit, or if you want to compete in 5mph classes forget about it. Not even close to worth it with an H. Dollar for Dollar will go lots farther in an M. A 39-mid 40's possibly later 40's M will have no problem getting into 4500lbs class especially with pressed steel. Getting an M to put down 60hp is easy on stock stroke and borderline impossible on stock stroke of an H.
 

After refreshing the short block assembly and getting a cam from Sonny at Bullit, spend all your remaining money on head/manifold flow work. My H is stock stroked, thin sleeved, 158 cubic inches total and will full pull (300 ft) in 3500, 4000 and 4500 classes built this way if there is enough traction to hold it. While it is not competitive in 5000 and up due to all the huge motor tractors that can get into those classes, it still can go over 200 feet in them.
 

I meant to add that if you can get a low-low gear set, you'll do much better in the heavier classes than I do with my regular gear.
 

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