Plugs still white...

[74 340 4speed]

A friend of mine had a demon on his 350 and he never could get it to run right.  Several carb guys tried to tune it, but it was to no avail.  He got an edelbrock, put it on the car and drove away without even touching it.  I would recommend a holley though.  I've got them on several vehicles and have been well satisfied.

[440Charger]

try inserting a small diameter piece of wire in to the air bleed , this will act as if you have a smaller bleed in place 

I'll give that a shot.  Thanks.

[440Charger]

Just checked three more plugs today while trying to do a compression test and found that each plug had a different shade of color.  One was very lightly tanned, one of tan, the 3rd was a light black.  Is it common to have different plug colorings?

[Chryco Psycho]

that sounds like an Intake leak possibly through the brake booster , which plugs are lightest?

[440Charger]

The #1 was the darkest, #5 was fully tanned, and #7 was very light tan.

I just checked the hose going from the brake booster to the intake, and the intake end of the hose has a metal threaded fitting and it's tight, but the brake booster end of the hose is not clamped and I was able to squeeze it a little with my fingers so I'm guessing that could be a problem?

[440Charger]

Ok I just threw on a hose clamp on the booster end and it's about as tight as I can get it.  Since it wasn't clamped it would just slide off the booster nipple easily so I'm sure that wasn't sealing. 

Any idea how much air that would let into the manifold while driving? 

Thanks Neil 

[ShelbyDogg]

Are you out driving down the highway, then pulling over to check color?

The only time I checked my plugs was during a hard pass down the drag strip, then shutting down, coasting off, then checking them after being towed back. 

Get an oxygen sensor and stop messing with your booster.

[Bullitt-]

That's probably not the problem...the gizmo that the hose goes on that plugs into the booster is called a check valve, it could be bad...do your power brakes hold vacuum?

[440Charger]

That's probably not the problem...the gizmo that the hose goes on that plugs into the booster is called a check valve, it could be bad...do your power brakes hold vacuum?

I'm going to check that next, not sure right now.

FYI - clamping down the hose did make a difference and now I need to re-tune the carb, and I felt more power on the highway.

[440Charger]

The vacuum is about 12