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MG MGA - HRG Derrington Head

Does anyone have a photo of an installation of an HRG Derrington head in the car and maybe some thoughts on what needs to be modified to fit one with 1 1/2" SUs.

I know the heater box would have to be changed for a twin cam type with the air intake on the left hand side of the car, plus heater tap. I am mostly interested in whether the starter switch mount has to be moved and what kind of brackets are needed for the choke and throttle cables. For example, can the twin cam brackets be used for these connections?

I also need a manifold for the 1 1/2" SU's with vertical hole mounts. I know it would be better with 1 3/4" SU's or Webbers but I'd like to see how it goes with the 1 1/2's first.

Thanks John

John Francis

John, send me your email and I will contact you.

M Wellard

See here:
Barney Gaylord

You can use a stock heater but must arrange a different heater valve - I've sent you some pictures. Many installations are intended for summer use and omit any heater. It isn't necessary to change to the Twin Cam heater, you can just plumb the lines to the existing connections.

The starter switch bracket should clear the SUs but you'll have to dry fit it to see for yourself.

The interference with the manifolds seems to have been restricted to the rather awkward modern MSX repro manifolds, and original manifolds shouldn't have that problem. I haven't had a problem even with the twin 45 DCOE set up I run.

You can reuse much of the stock SU linkage as well, and if you need anything, Burlen or Moss can supply it.
Bill Spohn

Thanks all

Surely the problem with the heater is that the 4" air intake tube from the grill has to be re-routed down the LHS of the engine bay as in the twin cam. Hence the suggestion for the twin cam heater box. John
John Francis

This thread was discussed between 08/03/2011 and 09/03/2011

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