Rewelding 2.7 heads or using 2.2 or 2.4 heads instead?
 

The title says it all. I have 4 out of 6 damaged heads. Damages are at valve guide level.

1 intake with missing chunk, see below
3 sliced > 2 exhaust, 1 intake

Can 2.2 or 2.4 heads can be used if ported?
Can 2.7 heads be rewelded solidly?

Man -- how did that happen???

2.2 or 2.4 heads should be similar to/better then /worse then 2.7 heads.

What sort of 2.7 do you have? (Year/model?) The 2.2 and 2.4 heads came with 32 mm intake and exhaust ports in the T's and E's and 36 mm intake and 35 mm exhaust ports in the S's. (And maybe something in between in the 2.4E's although I have yet to see specifics on one). The 2.7's came with 32 mm ports on the normals and 35 mm ports on the S's and the 76's and 77's. If by chance the engine is a European Carrera or an RS, then the ports were the same 36 mm as on the 2.4S. The stud pattern, valves and combustion chamber size are all the same.

So you should be able to use 2.4 or 2.2 heads, potentially without even porting them. Some people when they port engines will grind off the valve guide boss anyhow, so the head pictured may already be half way there (assuming that there is no additional damage).

Yes Like John said I would remove the guide and grind that Off then reinstall the guide and GO! It seems to me my rs spec motor is done that way Also

Heads are 35mm from a 911S. I think it happened to the PO when installing new valve, improperly i guess.

Heads i hace spare are from 2.2E or 2.4e

Can those dam,aged head be fixed? How permatnently?

Thanks!

I think the PO was doing something more then just "installing new (a) valve". I suspect that they may have tried to cram in a mis-sized valve guide or buggered the job up in some other way. There are other guys on this board who have rebuilt a lot more engines then I have have who will hopefully chime in with their thoughts. But given the really ham handed job that they did on the heads, I'd really question the quality of anything else that they touched in the engine.

BTW - You could fill in the data that I've collected on head porting since I don't have data for 2.4E's. Could you take a couple of measurements from the intake ports of your "spare" heads and send them to me. Specifically what is the diameter of the intake port at the manifold face in mm's? If you have inside calipers, repeat the measurement at .5, 1, 1.5 and 2 inches in. If you could also include the casting number and date (Year/Mo) that would be really helpful.

The damage shown in that picture screams to me that the valves touched the tops of the pistons hard! You could leave it, or grind it away and have a freer flowing head albeit with a bit less support for the valve stem.

Welding that would be near impossible, but could probably be done by tig , using a really small gas lens and manipulating the arc through the port, and feeding the filler through the valve opening.

I would get in there with a die grinder and really smooth things out :D