72’ Ironhead frame engine fitment issues

[ExplodingCoffinEmporium]

Bit of backstory, my buddy bless his ambitious heart had this 1972 IH, the trans took a shit, he got frustrated and was talked into altering the backbone to accommodate an evo engine. So he cuts off the backbone, which he no longer has and installs a very solid piece of tubing to allow evo fitment. I acquire this frame from him later on, and have now come to a point of deciding what to do with it. I really have no desire to throw an evo in it, I have a 77’ engine sitting around however. It would seem like quite a waste to find another IH backbone and cut it off to replace this one. Would it be feasible to install the 77’ engine and weld a new top motor mount into place? I know the 77’ oil pump is a fitment issue for older frames, or so I’ve heard. I guess just looking for some thoughts, thank you

[JBinNC]

Well, at least the '77 motor will line up and bolt into the motor mounts, and unfortunately, an evo motor will NOT. So, you are on the right track.

Jim

[TriNortchopz]

Some info on the older Ironhead frames that may be of interest:

OSKRG Research/Restoration Bulletin #1, REV.5

1952-'72 K & XL Frame Model Year
Determination Flow Chart:

http://www.harleykmodel.com/technical/frames/oskrg-1-v5.pdf

[farmall]

If the frame has a title it's worth fucking with.

Check the xlforum regarding oil pump clearance modification. It's been done.

[ExplodingCoffinEmporium]

It is a titled 72’

[ridgerunner1965]

im not a expert on ih sportys but a top motor mount is easily fabbed and welded on. the oil pump clearance could be challenging but nothing you cant figure out.