951 turbo head on 86 944 NA?

[Ed18]

I'm planning to install a 951 cylinder head to a 1986 944 NA. Any comment about this?

[9FF]

It will fit & function exactly the same as an na head but the hollow valves are more expensive and the ceramic liners can be troublesome.

If everything checks out its a straight swap.

[krystar]

nothing much different on the 951 head. 951 exhaust valves are sodium filled. i think intake valve is a smidge bigger.

nothing that'd affect performance significantly.

if u just got a good deal on a replacement cylinder head..sure why not

[Ed18]

Originally Posted by 9FF

It will fit & function exactly the same as an na head but the hollow valves are more expensive and the ceramic liners can be troublesome.

If everything checks out its a straight swap.

Do you think the ceramics gonna be a problem since it doesn't take that much beating (heat/pressure) compared to the turbo?

[Ed18]

What about the valve spring? Will it be compatible with NA camshaft?

[9FF]

Valves spring are fine. Ceramic coating only becomes a problem if its not all there, chipped, cracked, etc. otherwise you're good.

[Ed18]

Originally Posted by 9FF

Valves spring are fine. Ceramic coating only becomes a problem if its not all there, chipped, cracked, etc. otherwise you're good.

So what's gonna happen if ceramic coating's cracked/chipped? Will it be a problem in terms of engine performance?

[9FF]

Quote de 9FF

Valves spring are fine. Ceramic coating only becomes a problem if its not all there, chipped, cracked, etc. otherwise you're good.

So what's gonna happen if ceramic coating's cracked/chipped? Will it be a problem in terms of engine performance?

Check the exhaust coating to see its all there and not degraded. Its not really a performance issue, its simply if that coating is failing there is no easy way to fix it whereas on the Na head you don't have that problem. Suppose in extreme case loose bits could end up in the chamber and cause damage but I would think that unlikely due to the gases going the other way.

[Ed18]

Originally Posted by 9FF

Check the exhaust coating to see its all there and not degraded. Its not really a performance issue, its simply if that coating is failing there is no easy way to fix it whereas on the Na head you don't have that problem. Suppose in extreme case loose bits could end up in the chamber and cause damage but I would think that unlikely due to the gases going the other way.

Thanks. I'll try installing it and keep you posted about this. Maybe i'll add some pictures on this posting.