Valve included & axis angles

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I've tried to search the archeives for the Performance Fitting & Service Notes for the Norvil Commando Production Racer.
In there, they show diagrams of how to modify the pistons.
The diagrams show the angle at which both inlet & exhaust valves are rotated horizontally about the wrist pin centreline. What is this angle? (28 degees?).
The inlet & exhaust valves are also inclined vertically to each other. What is this angle? (60 degrees?).
The reasons I ask, is because I have to get valve pockets machined into my high compression pistons.
Thanks
 
Rather than trust the book, how about sticking some valves in the guides, extending them, and measuring the angle with a protractor off the head's deck? Or, without a valve, measure it off of a pilot stuck into and extending out of the guide.
 
According to the factory drawing they are rotated 25 degrees. The intake valve is 28 degrees from vertical and the exhaust is 30 degrees from vertical. On a standard head. Jim
 
heres a silly picture :
Valve included & axis angles
from here :

http://commando.yolasite.com/ which ISNT the Norvil P. R. head . :cry:

This IS .
Valve included & axis angles


P. R. is same as Dunstall , which is Er , :oops: developed from Domiracer - perhaps , Doug Hele . Er . reangled anyway , and hemisphered chambers .

http://www.squidoo.com/paul-dunstall-tuning

cant dig out drivle at the moment , every 10 yr old knew it was 26 1/2 degrees . :oops: maybe , If I remember right , perhaps . :?

valve was swung down to clear & intersect rocker . Norvil road tests should say . ?
 
Only about one hour ago i was on the phone to Mick Hemmings as he is amongst other things pocketin my new pistons to match the big valve head he is doing. He said because of details missing from the drawings released by Norton the best way to cut pockets in right place was to assemble engine and mark their position thru valve guides then in his case at least as he has changed guide angles to fit larger valve he new where to machine pockets .
He added that even with standard guide angles it was best way to make sure you cut pockets in right place.
 
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