Intake valve's anti-reversion cut

[Lasse]

I can't find anywhere my book "How to Build & Modify Chevrolet Small-Block V-8 Cylinder Heads" by David Vizard.

Can someone tell me what was correct angle for anti-reversion cut in intake valve? I was making those cuts and forgot that angle...

[Lasse]

OMG, I just found that book. I have moved some time ago, so my belongings are everywhere. Mr. Vizard recommends 25 degrees for angle, does anyone have other experiences?

[rookie]

Are you talking about the edge on the combustion chamber side of the intake valve?

[Lasse]

Originally Posted by rookie

Are you talking about the edge on the combustion chamber side of the intake valve?

Yes. I mean that thing.

[rookie]

I have David's Max Perfomance Budget Smallblocks book and he just shows a picture of different ways of facing valves but does not give any specific angle, maybe he will chim in on this subject.

[Lasse]

Originally Posted by rookie

I have David's Max Perfomance Budget Smallblocks book and he just shows a picture of different ways of facing valves but does not give any specific angle, maybe he will chim in on this subject.

Yeah, I saw same thing, I have that book also. But I remember David treat that thing more detailed at book "How to Build & Modify Chevrolet Small-Block V-8 Cylinder Heads", but I lost that book. Now I have found it and David said 25 degrees. I cut some valves to 30 degrees when I understood something is not right. Cut seemed too narrow (I have done it some times earlier). Then I stopped doing that and I tried to remember what was that angle. Thank god I found that book. It was in one box what I was used when I was moving. I don't know how accurate this angle has to be and how much it affects, but I want do anything what I can for not to polluting intake charge. Look at my another topic about compression ratio.