5M head onto 7M block

[matt4u]

I gather this can be done but cant find any info on it, has anyone done it?

[big_boy]

can be done theres a slight difference in water jackets so dont know how affective cooling will be as 5M uses 4 1/2 rounds per piston & 7M is 3 out of the 4 1/2 rounds & 2 holes between each piston also 5M has a larger head volume & 7M have a bigger voulme in the piston insted also timeing gears are different for some as some 5m are square teeth (later ones are ment to be round but have never seen this) & 7M are round also from memory timeing gears have a different sized hole for the cams & different 3`s of teeth il ckeck that for ya if you want

[matt4u]

That would be good if you could, From what I gather it basicaly makes a 6M, you use the 5M eletrics and get similat power to a 7M

[Toymad]

I gather this can be done but cant find any info on it, has anyone done it?

I'm running one now.
Basically, it will work. Once you get into it, 5M is two valve and 7M four valve and the pistons have recesses to match. So you need to put the 5M pistons in the block for the 5M head. If you have the earlier 5M pistons that are dished, the compression ratio is 9.2:1. If you use the later "domed" 5M pistons, the c/r is about 9.85:1.

There are things like the timing and accessory belts to look at too; will you run the 5M alternator or the 7M's unit? What about power steering and water pump? Air con? If you use the 7M crank pulley, you need to source the right pulleys for the mentioned accessories. I "played" with my 5M crank pulley as I wanted it all to look factory 5M. The crank snout on the 7M is larger in diameter and slightly longer than the 5M crankshaft.

I also played with the injectors and air flow meter, but I'm not going to put that up here - pm me and I'll happily fill you in on all the (long winded) details......