merging a 1F and 2F

[TULAX17]

I've done a little research around the forum, and despite quite a few threads on this subject I would appreciate some validation before diving in...

Situation:
- I've got a 12/73 or 1/74 1F. It has a nicely rebuilt head, but a cracked block.
- The best replacement option I found is a long block from an 86 fj60 that is in good working order.

Questions:
1. Would my 1F head work on the 86 2F block, or would oil flow or anything else be a problem.
2. The seller I'm getting the 2F from has offered to pull off any parts where I can re-use what I have on my 1F? What external parts from my 1F could I transplant to the 2F (valve cover, side cover, waterpump/fan/thermostat, crank pulley, bellhousing, etc)?

Thanks in advance.
-Steve

 

[flash02]

Does your F have the small oil line running from the crank case and connect to the rocker assembly, if so you might be SOL. 1974 was a transition year; the F engine was changed to include the new full flow oiling system that the 2F would later have, I am not sure when this F hybrid was introduced. If your engine has the oil filter mount on the right side of the engine and not on the left then you probably have what is referred to as the F 1.5 and with this you may be able to use your old head on the new block. I would suggest you look in the FAQ section and read the countless threads regarding F and 2F head swaps. You may just want to sell your rebuilt head and just go with a complete 2F engine. My FJ 40 is a 10/74 with the improved F engine, I like this engine as it has a much improved oil system but retains the low TQ that the F engines were famed for.

Good Luck!

Corey

 

[TULAX17]

thanks Corey.
I attached a couple of pictures from when I had the head out to rebuild. That's an F.5, right?

-Steve

 

[Godwin]

Looks like you're in good shape. Notice the extra hole in the #4 rocker arm spot, that's for oiling of the rocker arms.

The F pistons are domed while the 2F pistons are flat tops. If you swap in domed 2F pistons you can have an engine with higher than normal compression. I ran a setup like this, '74 F head + '85 2f block, for a short time and the torque increase was noticeable. Compression with this engine was ca. 195 psi as opposed to the stock 160. If you do not run the domed pistons the compression will be lower, how much I don't know.

 

[TULAX17]

Thanks Jim and Corey. That at least gives me some options.

 

[slickrock]

Looks like you're in good shape. Notice the extra hole in the #4 rocker arm spot, that's for oiling of the rocker arms.

The F pistons are domed while the 2F pistons are flat tops. If you swap in domed 2F pistons you can have an engine with higher than normal compression. I ran a setup like this, '74 F head + '85 2f block, for a short time and the torque increase was noticeable. Compression with this engine was ca. 195 psi as opposed to the stock 160. If you do not run the domed pistons the compression will be lower, how much I don't know.

I wouldn't run flat and domed pistons tgether. I gave up on swapping an F.5 head into my F block for this reason. Compression would be way low.

 

[Godwin]

When I ran the F head on the 2F block I swapped out the flat-top pistons for domed. The engine was being rebuilt anyway so changing piston types was simple. This combination gave the compression bump.

Not sure what you're saying about running flat and domed pistons together, it's any either/or situation.