While you've got the intake off, pull the lifters (one at a time) and inspect the bottoms for unusual wear. Make sure you drop them back into the holes they came from. You could have a lobe that's getting wiped although I don't think the vacuum variation is all that unusual.
One thing, never give up on it . We are all here to help one another. That's why I love this forum. Great guys an girls.
When it was running, did you try and smother the carb, and see what happened? I've never had a aftermarket cam that made the advertised vacuum.
Bingo!!! My experience is basically same... The Stage-1 Trick Flow in my injected 5.0 Bird would idle around 11" at 800 RPM... That cam is .499/.510 lift and 221*/225* dur... I dunno what the compression ratio was, but it made 170 psi cranking & I'm at sea level...
Thanks for all the ideas. I've got the intake and timing cover off now. I just had to check to make SURE my timing marks lined up. I've got a degree wheel and I'm degreeing the cam tonight just to verify that everyting is as it should be. Due to the size of the intake ports on these heads I have very small sealing area for the intake. Mr Gasket has some intake gaskets made for applications like this so I ordered some . They're only a few buck more than the standard Fel-Pro's. Good to know that others have seen vacuum different from advertised. I will post again when I know more
Degreed out the cam last night. The cam card said that @.050" intitial lift on the intake should be at 6 degrees BTDC. Mine was @ 2 degrees. The COMP CAM timing set have 3 key ways. Circle , square and triangle. I set the gears to the circle originally. But I think these readings are telling me I'm 4 degrees retarted ( like an old smog motor). As soon as I get some more time I'll check the other 2 settings and see if one of them will give me the 6 degrees I want.
Upon CLOSE examination (with my glasses ON) of my timing set, I discovered the square is actually a rectangle with rounded corners that looks remarkably like a circle(without my glasses on).Thus 4 degrees retarted. Now it's on the REAL circle(with glasses on). I am now reassembling the motor . I'll report back on what I get for vacuum when I'm finished.
At Last! After having a fender bender, replacing the shifter tube in my Explorer, and the harmonic dampener in my Mountaineer I finally got back to my Maverick, and the gas tank was leaking in multiple places. I replaced the tank with a 68 Mustang tank.( Thanks Mavaholic for a Great Tech article) So why the happy face? The Maverick now runs much better and I can hold between 15-16 lbs. vacuum. (I really have to watch those cam timing marks closer!) I'm still fine tuning the carb and timing. Right now it appears to run best @ about 30 degrees BTDC. This seems a little advanced to me but it starts when it's warm with only a little extra effort. Is anybody else running their ignition timing this far advanced??
