Engine is a 318. 360 intake with Holley 650 carb. 360 cam. Tri y headers, 2.5" x pipe and dynomax mufflers. Stock 318 otherwise.

I was coming up a hill, running hard in third. Truck had been running fine. Got to the top, stopped to make a left turn. Went to take off, and had a noticeable miss. Next stop sign, had a stumble that increased every time I stopped and took off again. Made it to an Oreilys and got carb and choke cleaner. Sprayed intake and carb, and as I sprayed the back passenger side of intake, and back passenger side of carb, the idle bogged. Wouldn't it idle UP with a vacuum leak?

I am running the carb with an upside down spacer. Carb is a known good carb, and came off a running driving 318 very similar to my motor setup.

I haven't had the chance to check timing. Last it was checked, was before headers, exhaust, and carb swap.

I DID have an intake vacuum leak, which was just corrected. Intake was pulled, and new gaskets were installed. I rechecked the bolts, and all were still snug, minus 2 which I was able to get a hair turn on them. Nowhere near where the spray/bog is happening.

I do have a header leak on the passenger side. I need to remove the header and clean the mating surfaces again/better (maybe?) could I have sucked a valve because of the exhaust leak?

I picked up a set of cheap champion plugs, since the one I pulled out, seemed tired. It had been in a rich scenario, and now a lean(er?) scenario. It's been a few thousand miles, so it can't hurt.


Forgot to mention. It idles at 1200 rpm (running 360 pullies, needs to idle a tad higher for alternator charge.) but when it was running badly, it was idling at 850. After I shut her off, and restarted her, I was able to drive her home no problem, idling back at 1200 when I came to a stop.

Another thought was the accelerator pump. The carb had been sitting a few after being removed from a running vehicle, so I picked one up to put in for giggles. I adjusted the screw/spring to 15 thousandths, like I read on Holleys website. I haven't had a chance to look down the carb to see if I'm getting a good pumpshot, since it got dark.

What am I missing?!? Ignition is a factory electronic ignition, which replaced the points.

Oh and she has a hard time restarting. If she idles, and I shut her off, quite a bit of cranking, and she will fire up. No amount of pumping, slowly depressing gas, or cussing will get her to fire sooner. Just crank and crank till she lights off.

Any ideas?

Ok so put the new plugs in. Retuned to 14* timing.

Idled it down to 800 and resprayed, no more idle up or bog down.

Drove to my friend Tim's house about 20 miles away. Ran ok.

We tuned it with a vacuum gauge and got to 18 lbs at idle (~800 RPM's. kept changing as we adjusted)

The PCV valve started ticking/clicking, making a buzzing sound. Had to order one and a grommet.

I'm not sure where timing is or how many turns on the idle air screws. We tuned to achieve maximum vacuum. It runs a LOT better. Still has a SLIGHT hesitation. I'm getting a decent pumpshot. My idle is erratic though. It will idle at 1300, then if I shut the truck off, she will fire up and idle at 900


Haven't pulled a hill in third yet, but I'm tempted. It's running decent enough.