new owner of 250 crossflow

[rocklord]

Is the 12-counterweight crank only available from Oz? If I ask for one what is it put in? What year? Is it for the 250 overhead cam crank? Do you think it is available from rebuiders or only new? Thanks Marv

The 12-counterweight crank is only available from OZ. It was used in the EF Falcon of the mid-90's with the 4.0L OHC engine. If your looking for one, that's what you will have to ask for. You may be able to get one from a rebuilder, or from a recycler (wrecking yard) but make sure it has been crack checked before purchasing (it's a long ways to get a replacement).

This crank will drop into a 4.1L crossflow block with the casting code 84DA or 86DA because they use the same rear main seal. Earlier blocks will have to be machined to accept the rear main, or the rear flange of the 4.0L crank turned down to accept the earlier seal (the disadvantage of turning the flange is you could weaken the area where the flywheel bolts go in). The advantage of the 12-counterweight crank is the ability to rev the engine above 6000 without fear of failure; the x-flows get very bad harmonics at around 5800-6000rpm and the balancer or flywheel may shake lose.

Hope this helps.

 

[MustangSix]

On the flywheel, I used a 157 tooth flywheel from a 250. It bolted on and the 2-bolt starter from a 200 worked perfectly. The two engines I got from Oz had auto trans flexplates on them, but they were also 157 tooth and the same diameter. You can easily find a neutral balance 157 tooth wheel for a 289/302 and use it. Anything for a 250 is getting harder to find.

The US 250 crank won't work in an Oz 250 block. Different mains, different crank snout, different rear seal. Also, forgot to mention earlier, but the US distributors won't fit the Oz blocks either.

This whole bottom end conundrum was the reason I set out to build a US/Oz hybrid.

 

[6cylfever]

Well I finally tore down my crossflow. I found BF-2 between number 4-5 valves cast on the cylinder head. My oz supplier of my engine plate sent me the wrong stuff off a later crossflow. The crankbolts are 8 ml not 7/16" and the engine plate is smaller. I've going to use t-5 instead of the automatic. I haven't got a 4 speed bellhousing to adapt, so I'm looking into using a low mount starter and going with 289/302 bellhousing and building the adapter to the block.. Is this a possibilty? Do you any one else know where I can get a 12 counterweight crank? Do I need the vibration pulley to mach the crank? Has any one place a supercharger on one of these engines? I don't like the sound of a turbo. Marv

On the flywheel, I used a 157 tooth flywheel from a 250. It bolted on and the 2-bolt starter from a 200 worked perfectly. The two engines I got from Oz had auto trans flexplates on them, but they were also 157 tooth and the same diameter. You can easily find a neutral balance 157 tooth wheel for a 289/302 and use it. Anything for a 250 is getting harder to find.

The US 250 crank won't work in an Oz 250 block. Different mains, different crank snout, different rear seal. Also, forgot to mention earlier, but the US distributors won't fit the Oz blocks either.

This whole bottom end conundrum was the reason I set out to build a US/Oz hybrid.

 

[rocklord]

Are you sure it's not HF-2 between the 4-5 valves? That stands for Honda Foundry; Honda cast the heads for Ford.
Look between the No 1 and No 2 intake ports on the side; is there any markings there? Something like C1, C2, D1, or E1. That will give you an idea of the chamber size.

As I said before, check the casting code of the block to make sure when the engine was made, that way you can be sure you get the correct parts.

The 12 counterweighted crank is only available in Australia; if you find one you will need the harmonic balancer (vibration pulley) for that crank. Even without this crank, the engine will rev up to 6000rpm.

If setup right, the crossflow will make 200HP easy; some in Australia are getting 300HP+ NA.

Money=HP; how much can you afford?