Spitfire Joining/mounting Euro manifolds on Spitfire

[Norton47]

Hi
I am installing a HS4 and Euro type exhaust manifold on my 75 Spitfire. According to the parts diagrams and some sketchy information in the service manual, the intake and exhaust manifolds are bolted together on this type of installation.
My question is with the manifolds snugged up to the block there is a gap between the manifolds where the joining bolts are inserted and which when tightened would seem to cause stress on the manifolds and mounting points.
Should there be this gap? Are there fasteners suppose to pull the manifolds together or not? If not, should I shim between them?
I have attached a photo to show the gap. Thanks in advance!

 

[Trevor Triumph]

I'm thinking a washer/ shim. I used the Euro manifold and carbs but have a set of headers. My thought was that improving the intake would not work as well without improving the exhaust. Besides I had the header first and then convinced the treasurer of the project that headers, Euro intake and carbs, and high compression pistons would work best as package.

T.T.

 

[dklawson]

I have a set of dual carbs waiting in the attic for when I feel our son is "ready" for them. Like Trevor, our Spit currently has a header instead of the cast iron exhaust. Sorry, cannot offer any real advice on the bolt-together question.

There are standard and heavy-duty gaskets. Others will correct me if I am wrong but I believe the standard gasket was made for the U.S. market cars using the cast iron exhaust manifold and the gasket combines the two center exhaust ports. The heavy-duty gaskets treat each intake and exhaust port individually. Buy whichever is appropriate for the exhaust you plan on using.

The image below is for the gasket with the siamesed exhaust ports.



The image below is for the gasket where each port has its own "hole" in the gasket. Sometimes referred to as the heavy-duty gasket.

 

[70herald]

I wouldn't be to worried about the gap, tighten the manifolds on to the head, and then tighten up the connecting bolts. If the manifolds are correctly tightened you aren't going to move them anyway.