yellow rose said

I have done it several times. If done incorrectly, it will lose power over the 1.88 valve.

It also depends on lift. If I get close to .500 lift NET, I lay out the gasket line around the cylinder, then lay out where the valve is. Then you blend OUT to the line and DOWN about .100 or so. Do it for every cylinder.

If you are running some ancient deal with .450 lift you can get by with out the notch. I can tell you, that on a flow bench you can see the difference with the notch. And on the dyno. And in your time slip.

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rumblefish360 said

NO!

And never worry about valve shrouding. While you want to avoid it for best performance, there's more than just a few factory examples out there in the world that have a bad case of valve shrouding but yet, the engine makes ridiculous power.

Oh! Almost forgot! David Visars has a good book on porting heads that has a topic on this issue. While the book is not an in depth technical book with hard to understand jargon, it is certainly worth the price of reading.

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