Head porting?

Coyd

Well-Known Forum User
I'm rebuilding my engine, the head has had extensive porting. Whats confusing us is why the ridge has been left on intake valve just above seat.
It’s all been smoothed out on exhaust side. Just wondering if there was any reason, it was a Dave Jarman engine
 

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Rob Gaskin

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I can't answer your query but to me the exhaust appears to have a bigger 'lip' as if the seat is low. I'm not experienced with head porting but a couple of people on here are.

What history have you got for the engine?

Did you get Dave to rebuild it and if so ask him?

If not when did Dave work on it and do you have any supporting paperwork? I'm thinking it is probably a long time ago because it's now worn and needing a rebuild.

The reason I'm asking is that you have to be careful with old engines and their history.
 
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Coyd

Well-Known Forum User
We’re cc ing the chamber’s, so what we take out we’ll balance that out by skimming head.
We’re wanting 10.5 to 1
Measured it at 10.75 to 1 so should be doable.
 
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