1946 John Deere a

jadbf150 · Aug 9, 2018

Good morning everyone,
My name is Jason and I?ve got an 1946 all fuel John Deere a. I?m looking at rebuilding the engine and adding a little more power for the local pulls. After looking over all the previous posts on this sight I think I?m going to put late A/60 aluminum pistons, have the cam ground, valve job, port and polish the head, Murphy?s manifold, and rockers. Also think I?m going to have the head milled .150 to make it comparable to the late a head compression wise. I was hoping someone could give me an idea on what I can expect with horsepower and compression ratio? Also, anything I might be missing?

forty40 · Aug 9, 2018

(quoted from post at 05:26:07 08/09/18) Good morning everyone,
My name is Jason and I?ve got an 1946 all fuel John Deere a. I?m looking at rebuilding the engine and adding a little more power for the local pulls. After looking over all the previous posts on this sight I think I?m going to put late A/60 aluminum pistons, have the cam ground, valve job, port and polish the head, Murphy?s manifold, and rockers. Also think I?m going to have the head milled .150 to make it comparable to the late a head compression wise. I was hoping someone could give me an idea on what I can expect with horsepower and compression ratio? Also, anything I might be missing?

Everything is going to help except porting. Unless there is experience porting for a specific application, it will cost HP.

jadbf150 · Aug 10, 2018

Ok, I?ve been hearing that from more people. I think
I?m going to forget about the porting. I had a chance
yesterday? to talk to a couple experienced Deere
guys. Think I got my plan in order. Thanks for your
help.

Rottenground · Aug 16, 2018

I have the same tractor as you. Mine is bored, has late A aluminum pistons. My head has been milled .150, I gasket matched the ports on the head and manifold and barely polished it. Mine has a stock gas manifold, stock cam, and stock rockers. It runs good, starts fine, made about 115 psi of compression compared to the original 70 psi. I wished I would have found a late A head and milled it instead. To get the compression up some more. It weighs right around 4500 with me on it, Most of the time I pull up to 5500 or so. Before I done all that it would power out with just a little weight on it. Now it will either spin out or the front will come up in first gear- still lacks some for second gear. I haven't put it back on the dyno since I done all that before it made about 32hp- I figure its right around 40hp now. It works for me.

jadbf150 · Aug 16, 2018

Lastv year I actually replaced the cracked head that was on the tractor and didn?t think about changing it the newer head. Lesson learned I guess. I was looking to get 45hp and it seems like I?ll be close due to what your saying. I figure if and when I decide I need more I will jump up to an aftermarket head.

1946 John Deere a

jadbf150

Member

forty40

Member

jadbf150

Member

Rottenground

Member

jadbf150

Member

Similar threads