Cylinder head swap

[ryniobl]

Hello
I tried to find some info about cylinder head swap onto 323 block ,but google doesn't return anything interesting....everybody swaps whole engine not only cylinder head.
The question is: is there anything other than original that fits 323 block?
One bmw guy told me that 325 head from m20 and m50(needs to swap sprocket wheel) will fit without machining, but since he's got some ''personal problems'' I can't really trust what he says and we need to be sure before we put money in it and we don't have any parts to compare...
cheers
Richard

[Jeroen]

Not sure about the M50 heads, but yes there are 'improved' M20 heads that go straight on. Details on the different heads below. What head to choose depends on the engine modifications you have in mind.

Basis: 200 head The E21 320/6 and 323i use head 11 12 1 264 200 aka the "200" with 34mm exhaust valves and 40mm intake valves, later renumbered to 264 299.

Upgrade: 731 head In the later M20's (2.0 M20B20 and 2.3 M20B23 like in the E30) you can find the next version: was 11 12 1 277 731 aka the "731". This head was the same as the 200 but featured larger intake ports: 36.5mm

Final: 885 head The final version was 11 12 1 705 885 or "885" introduced in the 325i. Ports were further enlarged, valves were larger (36/42mm) and the combustion chamber was redesigned to improve flow and thermodynamic efficiency.

The Eta or 325e head 11 12 1 272 649 (34/40mm) or the later 11 12 1 713 019 with larger valves (36/42mm) is less useful. Designed for low revving only and therefor it only has 4 camshaft bearings instead of the 7 all other heads have.

[nas80]

there is no point putting an m50 head on an m20 block, when you can fit an m50 in?

[Mihajlo]

how is possible to fit m50 head to m20 block?

[e21jps]

how is possible to fit m50 head to m20 block?

it is NOT possible to fit m50 head to m20 they have internal timing chain and m20 has external cam belt

also note the 885 head has a larger dome shape combustion chamber so it really requires dome pistons to match otherwise your engine will have very low compression!!