Big Block Gear Drive On A Slant?
And why is the floating idler system no good? That's what I intend to use.
The issue is there are two different gear sizes. When the engine is in acceleration, it has one gear (I forget which gear it is...the smaller or the bigger) that drives the cam. When you lift off the throttle (or worse yet, if it's a stick and you're at WOT and push the clutch) the other gear slides over and takes over driving the cam.
I've seen as much as 10 degrees of cam movement with this system. The usual is about 7-8 degrees. It varies from drive to drive, deck height and who knows what else. But 7-8 degrees is about the average. That's a lot.
I learned this the hard way. I did an engine that had enough P/V (because I always check) and it went out and bent some valves. After I varied I wasn't on dope when I did the first measurement, I found out it would move the cam timing a mile. Hence, the bent valves.
That's the quick of it. I've heard some unverified stuff that I don't like to post so I usually save that stuff for private conversations because I don't have the ability to test what I was told.
