JD (A) stroke

[Anonymous-0]

I'm building a stone bolt pulling tractor this winter and my question is What is the largest stroke I can put in a late model A using stock rods? Will 7 3/4 stroke work with ALOT of grinding and an offset ground cam.

 

[toot]

yeah a 1" add on the stoke can be done.. yes, lots of ginding, dont know what you plan to use for pistons, factory type pistons will be pulled out the back of the jug, so you cant use oil rings, and will be too tall without some removal of the current top.

 

[39 A]

You can go to 7 3/8" without doing any grinding, that is what I have.

Call Josh Blackburn and he can tell you different options.

Josh has posted his number many times on here it is 989-277-5366

 

[2-banger]

i put a 7.5 crank josh did for me in my a just fits ..i think josh said 7 3/4 will fit using diff rod..id call him

 

[BushogPapa]

That and one of "Extreme's" New Blocks and you would be getting there...

Ron..

 

[toot]

like I said it will work, theres one in my barn, been running for 15 years

 

[Josh Blackburn]

We have ran an 8 inch a with stock rod journal before. just takes a little more clearancing.

 

[FOX-G]

Helped a friend put an 8" in A about six years ago and still runs great today. The best thing he did was drilled and tapped the rod to accept an allen bolt. Which made it go by the cam alot easier.
However do not rule out going with an offset rod even at 8 1/2 inches you would have less grinding inside the case, and because of the crank pin journal being much narrower may be stronger.
Most people go this route because they do not like welded rods. When in fact they go with a stock rod with increased strokes they make the rod the weakest part of the engine.