EXHAUST MANIFOLD MODIFICATION

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The following article was submitted by

ALAN OSBORN ; www.aoservices.co.uk

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EXHAUST MANIFOLD MODIFICATION

Quite modest gains can be made by getting the exhaust manifold to a proper shape.

As found often the exhaust hole is up to 2/3 covered with casting flash.

Simple grind it away with a rotary Burr in the end of your Black and Decker!.

To ascertain where to cut too, examine the exhaust gasket you pull off and you should see marks each side which correspond to the head holes and the manifold holes.

Obviously the gasket needs to be made to this full size as well.

So refit a gasket to the head (firmly) then cut it to align with the head hole.

If the head is off the car this is a lot easier.

I have used a strong penknife in the past. But do NOT let any of the swarf get back into the engine/head!

Then strap the gasket onto the exhaust manifold (Couple bolts will do) mark the ex-manifold accordingly.

Whittle away.

You then have to reset the mixture for best gains, it should go weak due to better extraction, hence you have to richen it a touch.

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ALAN OSBORN ; www.aoservices.co.uk

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