I have a 300 with a Comp 260 cam.
Can i adjust the valves the easy way (every 120° following the firing order)?
Many thanks to all.,... jack

 

Yes. That is how I recommend it.


Adjusting the valves on a 300 is EASY. For beginners I recommend writing down the firing order, 153624, thusly:

1 5 3
6 2 4

With a breaker bar or long handled ratchet and a 15/16 socket rotate the engine damper until the timing mark comes up to top dead center. Watch #6 cyls and #1 cyls rocker arms as you do this. On one of these two cylinders the exhaust will just be closing and the intake will start to open as you approach top dead center. If that happens on #6 then adjust #1. If it happens on #1 then adjust #6, because these two pairs are matched, as in the diagram above (5 & 2 and 3 & 4 are the other two matched pairs). So lets say you just adjusted #6. The next cylinder to adjust in the firing order is #2. Rotate the crank about a third of a rev, watching #2's buddy, #5. The exhaust rocker for #5 will be closing and the intake starting to open as you get to TDC. Adjust #2 when the two #5 rockers are in alignment, one closing and one opening.

Continue this process until you go through all six, then go through it again, to double check. With this method you can adjust all six cylinders with only two revolutions of the crank.

To speed things up you could mark your damper in three places spaced 120 deg apart. But any more I dont even look at the damper.

With practice you can run through your valves in five minutes. It will take you longer to remove the valve cover than to run the valves. Whats more you wont even have to look at the damper, just find the cylinder in the overlap cycle and start from there, adjusting the buddy cyl. Good luck.

 

Thanks for this info, FTF. I had heard there was a technique to shortening this process, but couldn't find it.

Lately, I've been working on adjusting my valves, but have been doing things the long way. Start at #1 and just as the exhaust starts to open, adjust the intake valve. Then 5, then 3 then 6, etc. Go back to #1 and just as the intake finishes closing, adjust the exhaust. Then 5, 3, 6, etc. Which takes, at minimum, about four revolutions of the crank.

The problem I've been running into is by the time I get to the last ones, even just an 1/8th of a turn past what feels like zero lash will start opening up the valve. It's frustrating. (Any thoughts on this?)

Otherwise, less revolutions of the crank may negate that and get me a better adjustment.

 

AB: Thank You

What you described was the same procedure that Comp Cams said to use. I was questioning the necessity of such an elaborate procedure for such a mild cam grind (Comp 260).

FTF:
Thanks a million! Your advice has been a great help in the assembly of my basket case 300.

Once again, many thanks to all.,....jack

 

It's a play-it-safe method.

Generally, a cam cycle is like this:

start -----------> exhaust opens -----------------> intake opens --> exhaust closes --------------> intake closes ----------------> end

The exhaust closes shortly after the intake opens, so if you adjust the exhaust right when the intake is finishing and closing, the exhaust is long since closed and a while before it opens again (therefore on the flat side).

Likewise, the intake opens when then the exhaust is nearly closed, so if you adjust the intake when the exhaust is just starting to open, it's a while before the intake opens and past when it's closed (therefore on the flat side).

It's non-engine specific, and works for most any cam.