Thanks for all of the tips guys. I will have some time this weekend to fuss with it. I'll let you all know what I find.
I actually do enjoy it, these days. I used to just guess randomly, and I bloody hated it. Could never make it run right. Now I have tools, and I treat it like a controls problem. The inputs are initial timing, left idle mixture screw, right idle mixture screw, idle speed screw, and selection of Vacuum Advance Controller (B-26, currently). Outputs are a timing light, a vacuum gauge, a tach, a CO meter, and my qualitative impression of if it's running like **** or not. Change inputs, observe outputs, repeat until outputs match what I think I want. Then, road test, and see if that was really what I wanted. Hopefully I can get to the track this fall, and add ET, MPH, 60 foot, etc. to my list of outputs. So many experiments to conduct!
It is a lot of fun Brett, not always easy, but satisfying for sure. Holleys are jetted pretty fat out of the box. They can cover up other problems with an engine, but that doesn't mean the engine is running right. Get your car down the track when you can. You'll learn a lot about the car from a timeslip.
The other potential with a possible leaky diaphragm is that the vacuum leak might raise the idle just enough to pull on the power valve if the throttle is a open a tad too far. I'm probably saying that backwards but the throttle opening would still need to be in the right place for all of your adjustments to work. That would also coincide with the thoughts on the choke mechanism sticking or having had the idle adjusted from a step rather than dropped down to the curb setting.
They have these paper things called manuals, because there are too many variations and specs, to remember. The good part is they all involve turning with a screwdriver or bending. But you do need a slide ruler. Float adj. There are a ton of modifications that can be done, and you can mix and match many parts and make them work kick ass. All the way up to 1000 cfm if needed.
The short version is that the QJet is on its way back to the carb builder. I fussed with it for hours this weekend. I checked again for leaks. Removed it to check for binding issues, improper fast idle, etc., inadvertently exposed primaries, etc. All looked fine from the outside. Still wouldn't idle, no matter where I tried to set the timing (keep in mind that ran just fine with the Eddy carb). I could not get the idle stable enough to even check the timing. I made the other adjustments to the APT and idle mixture screws that the builder suggested. Nothing. So, after consulting with the builder, he had me send it back for re-calibration. Stay tuned (pun intended). I'll update the group once I get the QJet back and installed.
That's gotta be the worst feeling. The only thing worse would be if you got it back and it's doin the same thing. Just for kicks are you gonna put your old one on and see how it runs?
Sounds like the Q-Jet has some vacuum leaks in the primaries. If the primary shaft has those cheap brass bushings instead of the good bronze ones, it will continue to leak & be impossible to tune. The carb which was on my 67 when I bought it had the brass bushings & ran pretty crappy.
Nah. I'm gonna wait and try the QJet again. I ran a new stock hard fuel line from the fuel pump to mate with the front of the QJet. The Edelbrock has a side inlet and I don't want to cut the new hard fuel line or rig anything up just yet.
Thanks for the tip. I'll wait and see what the builder sends back. Hopefully he's figured it out and it's a matter of how he calibrated it and not what parts he used. I guess I'll know just as soon as I get the carb back and slap it on.
Hmmmmmm Very interesting. I will bet that it got bounced around in shipping and something happened to the float or something.I cant pic who i think you got it from getting it wrong.
