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Hi All. I am starting the long overdue task or febuilding my 1275 S engine. Starting with the easy bit I have the 163 head which has been in an acid bath and now ready to make a start. The head has been breathed on before (ported etc) but I want to convert to unleaded & skim it as the face has a smattering of corrosion where it has sat on a bench etc.
I am looking for the following info if one of you can help me out.
What the valve sizes should have been?
What the valve sizes can go to safely?
Inside diameter of the new valve guides?
Depth the cylinder head should be (from Rocker box cover to flat of head??)
Where can I get the unleaded valve seats?

I hope I don't sound like I know what I am on about (as I don't!) but my mate works on some top end stuff and he has offered to help me do all this but has no dimensions or sizes to work from.

Any help or helpful suggestions massively appreciated.
Cheers
Mark
PS I will get it crack tested as I know AEG 163 have a reputation for cracking.

Anybody???

I'll have a go Mark.

S inlet; 1.401" 35.5 mm

S exhaust; 1.215" 30.9 mm.

In my opinion those valve sizes are just about the biggest you can fit in a 163 head.
If you want a larger inlets you need to relocate the valve guides further apart as done on my Longman 12G 940 head.

As for deck height I'll have to measure the heads I have here, that is, if they haven't already been skimmed.

Unleaded seats.? I'll be having unleaded valve seats fitted to my 1805 S / GT head, but that has approximately 1 mm smaller inlet valves.
I'm not sure if there is enough "meat" between the valve seats to do that job on a 163 head.

Valve seats should be available from most good suppliers.

Measured both my 163 heads earlier.

One, which I believe is an earlier head has been well modded and skimmed.
The second one which is off my late 68 MK2 S measured 69.41 mm. I then measured a standard 12G940 which came in at 70 mm, or as near as damn it.

Hope the above info helps.