TrueBlue ChevyDude

Well, the 360 was on the lift, all buttoned up and ready to drop in. What happened, I don't know, maybe it was the full moon, maybe it was McNabb breaking his ankle, maybe it was the case of Yuengling Lager Light, but I realized that I'm a glutton for punishment, and the neutral timing needed to be moved to 4' advanced. This will probably help me out for now, since I still have 3.07 rear gears. So, off comes the clutch, the flywheel, the motor goes back on the stand, off with the oil pan and the accessories and the timing cover. Pop off the balancer and crankshaft gear and knock out the balancer woodruff key. No problemo.

So, for now I'm stuck not being able to get the rear woodruff key out with a screwdriver and hammer (soon to tap/thread it out)

I then realized that the new 4' offset key could go in either way, making it retarded or advanced. I need someone who knows for sure and could advance a gear drive in their sleep. Otherwise, with my luck, I'll sit down and think about it for 2 hours, come up with what I think is the right way, and learn that my already "top-heavy" motor is retarded another 4' because I screwed up.

If you were looking at the timing gears from the front of the motor (about where the radiator is), and assuming that the slot in the crank snout for the Woodruff key is facing up at 12 o'clock, which side does the crank gear offset "lean" towards when the offset key is installed properly so as to ADVANCE the crank/cam timing, 11 o'clock or 1 o'clock???


Thanks in advance, sorry if the above isn't clear, it made sense when I typed it! :chevy


[Modified by TrueBlue ChevyDude, 8:44 PM 11/20/2002]

EricVonHa

(I noticed that this thread has been sitting idle for almost 24 hours but it's had a fair number of views.) I was hoping not to be the first to post about this, but here goes!

The Chevy small block has a firing order that rotates the crank assembly in a clockwise fashion (looking straight at the balancer). Just for demonstration sake, let's say that Top Dead Center of the number one piston is Zero degrees. Then, looking at our cam card, it has a recommended intake center line of 110 degrees. If the cam was manufactured per the provided specs and we turned the motor over with a solid lifter and applied some measurements using a dial indicator, we would hopefully find that the intake centerline of the #1 cylinder was at 110 degrees. Note, that this is crank degrees. All measurements are taken with a degree wheel at the crank. So, basically, at 110 degrees of clockwise crank rotation, we should see that intake lifter rise to it's peak lift. (there's a lot more of a process here, but this wasn't the question, only trying to give some background).

To get more to the question, the cam specs may be off (cam not ground as advertised, you want to shift the power band, etc.) and you'll need to advance or retard the cam. In this case, advancing is the question. With that offset crank key, you would place it on the 1 o'clock position of the crank as you're looking at the front of the motor. Why? Because you are moving the crank gear thereby rotating the cam further clockwise and causing the valve events to occur sooner (say 106 degrees vs. the original 110). That's the meaning of "advancing the cam"-- the valve events occur sooner in the rotation. Picture if the woodruff was NOT installed and you could spin that crank timing gear freely; In order to advance the cam, you would spin it clockwise. The crank position does not change in this example, it's the cam position that does change. Hope this helps. :chevy

TrueBlue ChevyDude

Thanks for the run-through, everything you said makes sense. 1'oclock it is.

Now, if I can just install everything without moving the crank, I'll be good to go.

Degreeing the cam for the first time was not fun, I was sweating too much afraid to screw something up. It would have been much worse if I had to do it myself, thanks for the hand with that too!