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MG MGB GT V8 Factory Originals Technical - RV8 Header installation

I'm preparing to convert to RV8 headers. This is mainly to deal with the under-bonnet heat problem.
I've checked the archives and the pages on the MGOC.
I'd like to get some pictures if anyone has any. The pics on the MGOC board aren't working but more would always help anyway.
I'm especially interested in engine bay and also under wheel arch.
I've bought the kit from Mike Wheatley including the reinforcement rings which look to me as if they will do well as templates as well as adding strength when they are seam welded into place. The holes certainly look as if they are going to be awfully big.
I'm trying to find out whether any steering mods are necessary and anything else that I should watch out for.
My car is RB and I'm not proposing to go for twin pipes.


Yes the holes are big but also help to remove hot air from the engine bay - the wheelarch is a low pressure area at speed.

No changes required to the steering set up.

Watch out for how the brake line runs to the crossmember bracket - it is very close to the down pipe.

Also don't park with the wheels on full lock after a run - the tyre will melt!
Chris Betson


Take care with the position of the holes; dont just use the reinforcement rings as templates. My shell from the MGOC had the holes cut and the rings welded but they are not perfect for my MGBHive supplied, Guaranteed Exhaust Systems manufactured manifolds. RH side is very close to the front of the hole, LH side close to the inner edge of the hole. By close I mean less than inch.

Also watch the tail pipe under the rear axle, on full suspension travel the axle may hit the exhaust. If you have telescopic dampers at the rear there may also be a problem with the exhaust and the damper trying to occupy the same space.

From the bracket on the crossmember I ran my brake pipes up at an angle away from the manifolds to above the damper. Then through the inner wing and back to the master cylinder on the drivers side and across to the M/C in front of the heater on the passenger side. Easy to do and no pipework close to the manifolds or under the chassis rail. Make sure there is clearance for full suspension travel of course.

Geoff King

Marc, check your inbox - I found some pics that may be of use...

David - thanks for the pictures. Very helpful.

Now, I gather that the big trick is to get the holes in the right place and that the position is always a little different depending on the installation. So how is it done? I can only imagine that one uses line of sight to make the smallest hole possible to fit the headers in place - this hole would be in the central position. When one is sure that this has been achieved then the template is placed around that spot and the full hole is cut. Am I on the right track? It sounds primitive but I don't see another way.
I suppose that there is no way to do the job without the engine out.

Also I have to say that I am worried about melting tyres. How likely is there to be a problem with 7" wheels and 195s?

This thread was discussed between 20/03/2002 and 21/03/2002

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