You can't assume lining up the dots is going to get you to the correct intake centerline. There's a number of people that had issues with the dot method, and been unpleasantly surprised to find it was not where they assumed it would be.

When installing a camshaft, always use a degree wheel and dial indicator, and confirm the valve open/closing events match the cam card.

Especially with todays aftermarket cams and timing gear sets!
Not many cam companies have that great of grinding capacity or operators even run'n them.
Some dont even grind thier own.
The "advertized" ones are mass produced, many companies buy'm from the main "core" supplier ready to box.
So if one even one thing is off on the 1st one, the whole batch is.

While you're in there rechecking the cam events, make sure it looks like the lifters are rotating in the bores, and check the lobes for wear. Lots of rumors about break-in problems with hydraulic flat tappet cams. Might as well check while you're in there.

Ok guys I'm back. Sorry but haven't had time to work on the baby lately, but may be on to something...

On the good doctor's advice, I re-adjusted the valves. Started it up for a minute, and I had better vacuum at a more reasonable amount of ignition advance this time. Idling better but still not great.

So I backed the locknuts on the rockers off, put a dial indicator on the valve spring cap, and re-adjusted them again, watching for movement. On cylinders 3, 4, 5 on intake valves, and on cylinder 8 on the exhaust valve, the valves are beginning to open before I even get the locknut 1/2 turn tight after zero lash. Watching the dial indicator, as I go beyond 1/4 turn to 1/2 turn, the valve will drop .035" by the time I get to 1/2 turn tight.

So my thoughts were either rocker studs pulling out of head, or rocker interfering with valve spring cap. Does not appear to be either of these. I checked rocker studs with feeler gage, and don't have any gap between the hex on the stud and the head. Also pulled the rockers off and have no signs of wear except right where I would expect at the tip where they touch the valve.

I'm noticing, as I slowly tighten the nut to adjust these particular valves, just as the pushrod lash disappears, the pushrod will become very tight quickly. The other valves tighten up with zero lash, then slowly start to get more turning resistance on the pushrod, as I would expect.

So do I have collapsed lifters under these pushrods?

And if 4 of the valves were hanging open, how did I not notice any compression drop in these cylinders?

Thanks again

Did you soak the lifters in oil before install?

And cranking compression and running compression are 2 different things.

Also, are you adjusting while the motor is running?

If you are adjusting with the engine off, you need to loosen off the rockers until the pushrod spins freely between your fingers with very little effort. Tighten the rocker until the pushrod no longer spins easily but no more than that. That is zero lash. You can loosen and tighten the rocker a couple of times to make sure that you are actually at zero lash (I had to reset the valve lash for one fellow who had tightened the rockers down so far he completely bottomed the lifters to get the pushrod to "stop turning", then added more! The engine didn't run very well!).

From zero lash, add 1/2 to 3/4 turns. If the lifter is a slow bleeder, the valve will open as you turn down the nut. Don't worry about that, that's normal and the lifter will settle into proper operation when you start the car. Other lifters may bleed more quickly. Again, don't worry; as long as you are setting from zero lash the lifters should work correctly when the engine is running.

Start the engine and let it run for a few minutes to get the lifters bleed down or pumped up as needed. If the engine isn't running well and you still hear ticking, set the valves with the engine running. It can be messy but you'll get to hear the difference as the lifter adjusts to the preload. They should take about the same time to adjust. If you have one that adjusts very quickly it may be faulty.

If you really do have valves hanging open you'll see the fluctuation in the vacuum.

Back to square one I think..
With ign timing at 10 deg, it will start cold, pull 15" vacuum but only for a minute or two. Seems like once it gets warm, it starts idling rough, vacuum drops, and it dies. No choke connected so its not that.

So I advanced it back up to the 30-40 deg timing range again where it will run and keep a constant vacuum. Adjusted the rockers by backing them off till they rattled, then tightening slightly.

I watched vacuum and didn't see any affect to adjusting the rockers. When I got them all, I set ign timing back to 10, and I'm at the same point as before..rough idle, low vacuum, misfire and backfire.

Adjusting the rockers cold, engine off, I was able to get all of them to 'bleed back' to zero on the dial indicator after turning 1/2 turn past zero lash EXCEPT #8 exhaust. I can't push the pushrod down by hand to compress the lifter and feel it spring back up like the others. So that one is bad but the rest seem OK.

Is it possible the lifters are not pumping up enough and not opening valves enough? I'm still getting low oil pressure. When I was adjusting the rockers w/ engine running, I only had a trickle of oil out of the pushrods. #7 cylinder had an occasional spurt but none of the rest even made a mess.

Interesting problem.

I would think you would have better idle and vacuume if the lifters were not pumping up. Less durration and lift.

Its been years but I seem to recall running my engine with the valve covers off and getting oil all over the place. Then again I may have been doing this during a cam break in with a lot of RPMs.

Do you have a priming tool for the oil pump? When I do a new start up or if its been a long time between startups I typicly will prime the pump. With the valve covers off I look to make sure I get oil comming out of each pushrood. I usally have to turn the engine a 1/4 turn at a time to get them all working.


I would think you would want 10 to 15 deg initial and with the vacuum can another 15 to 20 deg so 30-40 deg timing doesn't sound that bad with vacuum adv connected. I assume you are measuring timming correctly with the vacuum can pluged and disconnected? With the 112 deg lobes and the small durration you should have a nice smooth idle and good vacuum for sure.

Have you re tried your compression test since adjusting the valves. I agree that your test should be higher as noted.

The overly rich plugs are interesting. According to Cliff R. he told me to keep the idle mixture screws as much on the lean side as I could and keep a good idle. This should be set while engine is fully warmed up. I have never had much luck with the edlebrochs personaly.

I would take a good look at your distributor and make sure every thing is working good also.

This concerns me, you should be making a mess with oil flinging all over. You may be doing some engine damage at this point. Time to start some teardown and inspection before you wipe something out due to the low oil pressure.