Vauxhall 1.8 8 valve cylinder head

[HAL2016]

If anyone knows what function the hole that’s between the two middle inlet ports has on my Vauxhall 8valve Caterham cylinder head has?...it’s slightly soothed up and butts up flush to the inlet manifold.. I can’t see what function it has but can’t see why it’s sooted up either.

[Sensibleboy]

It's years since I've looked at one of these. Do they have a water heated inlet manifold?

[HAL2016]

I had thought of that but can’t understand the dry sooty carbon deposits and no water came out when removing the inlet manifold either.. I’ve taken my Weber’s off for a full refurb and the manifold also..🤔
As an ex garage mechanic I’ve had quite a few of these heads off many years ago..but can’t for heck’s sake remember what that hole was for.. if it was just a casting hole why the dry carbon inside.. engine was running fine just removing the carbs for cosmetic reasons

[DVandrews]

I think it may be an EGR port, which is essentially blanked off by your inlet manifold. It’s years since I did the HG on my wife’s 2.0 Cavalier with ‘J’ series..

Dave

[HAL2016]

EGR.. port I’ll check that out..I have two old Haynes manuals and saw no references to it in the breakdown references although it’s visible in the photos..
Thanks

[Mignon]

I remember puzzling about that when I was doing flow development work on that head 30 years but I'm damned if I can recall what the answer was.

[227bhp]

An engine code or picture would have been useful, but I would agree with DVA as I've seen them in plenty of other heads. They run some exhaust gas through the head as it's a handy as a transfer port and cools the gas before it goes into the inlet manifold.

[HAL2016]

Thanks guys I’m happy to think this is an EGR port blanked off by my Weber manifold..
The block on my Caterham is Carlton/cavalier and as far as I’m aware the head is a Caterham tuned and reworked Vauxhall Carlton/cavalier head also.
John