[Gach]

What name brand?

[Shockwave78]

Crower 66056x3

[Stan Weiss]

I believe you did a cranking compression test on 4 cylinder. With the new nuts installed can you do a cranking compression test on all 8 cylinders?

Does anyone you know have the tools to do a leak down test on all 8 cylinders?

With the car sitting parked with no load on the engine will it free rev or does it act like it does when on your road test?

Stan

[Gach]

Originally Posted by Shockwave78

Crower 66056x3

What did they say to torque them to ?

[Shockwave78]

Crower said half a turn of preload, thats what i did. I can do a cranking compression test on all 8 tomorrow, I don't know anyone that has leak down equipment. When the car is sitting, it revs fine. I have checked the mechanical advance weights and springs, they are a bit sticky but intact, so I'll clean them up tommorow. I'm also going to check the vacuum advance tomorrow by disconnecting and plugging the lines and taking it for a drive to see if anything changes.

[Gach]

Haft turn sounds like allot. I’m not saying there wrong. I’m thinking when you said you back off the nuts it pick up on compression. Try doing this, adjust so theres no slack in the push rod then go 1/4 turn. You’ll know because they’ll be real noisy. As soon as you start it up. Here’s a possibility if you used the same push rods you had before the new cam. its a possibility their a tad to long and are still holding valves open a tiny bit. Just trying to eliminate that possibility.

[Shockwave78]

I'll give that a shot, the only reason I did do half a turn was I was watching the valves and they didn't seem to move at all. How long does it take lifters to bleed down usually? I'm asking to make sure that they are not bottoming out, though it does seem unlikely.

[Tim Corcoran]

Originally Posted by b-man

Make the valvetrain adjustable anytime you run an aftermarket cam.

X2.

[Shockwave78]

Could fuel vapor coming up put of the carb at wot be a stuck float needle?

[Gach]

Originally Posted by Shockwave78

Could fuel vapor coming up put of the carb at wot be a stuck float needle?

I don’t think so.

[Shockwave78]

What do you think would cause that only at WOT?

[Gach]

Originally Posted by Shockwave78

I'll give that a shot, the only reason I did do half a turn was I was watching the valves and they didn't seem to move at all. How long does it take lifters to bleed down usually? I'm asking to make sure that they are not bottoming out, though it does seem unlikely.

I’m thinking once there pumped up. They don’t bleed down unless car been sitting for a long time. It sounds like to me, after you back off and compression pick up, you went and put new nuts on and went right back to same adjustment.

[Gach]

I got think about that for a while have to run it through my mind.

[Gach]

I might have missed it, what kind of carburetor

[Shockwave78]

Originally Posted by Gach

I might have missed it, what kind of carburetor

Stock quadrajet rebuilt by me about 2 years ago. Ran fine before the engine rebuild.

[Gach]

I went back and reread what you said, yeah do a compression test on all 8 tomorrow that will answer some questions..mean while I’ll run this through my head. Still thinking sounds like a couple of things going on. Buy maybe not.

[Scarebird]

Why not a leakdown test? for more informative.

[Shockwave78]

I do not have the tools to perform leak down testing.

[Sirrotica]

Revision in the intake manifold is causing the mist to come out of the carb. Revision is caused by the cam timing being off, or the firing order being wrong. I would first check the firing order, if it's okay I'd be looking at pulling the timing cover, and rechecking your timing marks.

The bouncing vacuum gauge could be caused by incorrect firing order, it's the easiest thing to check, verify it's correct first.

From the description I would say the cam is retarded, causing the intake valve to still be open as the piston is on it's upstroke. Doing a cam change in chassis, it is fairly easy to think you have the marks aligned, and they are off. To add to this you have 3 adjustments to choose from with the timing gears.

Reread the directions on your variable keyway timing set, and double check your work.

I've been called many times over the last 50 years to fix situations such as this, and usually it's something overlooked when reassembling the engine. If it ran fine before the work was done, it a distict possibility it's in the reassembly process.

There is a slight possibility of defective machining, or parts, but 99 times out of 100 it's an oversight, it happens to everyone at one time, or another. All the guesses that the valve adjustment was causing the problem were incorrect. From my own real life experience, I'm telling you the obvious order of troubleshooting your symptoms.

[Gach]

That was one of first things I suggested cam timing, but when he found valve adjustment was off, and then it pick up compression once that was changed seem possible that could’ve been the issue, but let him do compression test tomorrow on all 8, and check valve adjustment. Then if that doesn’t change much then most likely its cam timing, thats what I’m thinking. Cams retarded.