Idle circuit screw response

[blazer74]

.050 idle tube doesn't sound correct. That would be a lot of idle fuel and the down channels are only  @ .040

To properly measure the idle tubes you need a 2" long # drill bit (Taper Length they are called.
Other wise you would need to remove the tube to measure the restriction which is at the lower end.

You refer to upper idle bleeds in the air horn that would actually  be the main air bleeds @ .110
The upper and lower air bleeds are in the float bowl housing. uppers at the top above the down channels and the lowers in the actual bore itself.

[raf2330]

Switched the numbers, oops. .040 idle tube. Had them out during rebuild and checked with Cliff as he  sent me a pair with .036 in kit. He told me to put the .040 back in. Thanks blazer74.

77cruiser, I don't know about the slots. I'll check when I pull it off this weekend.

[raf2330]

Been messing with truck this morning and think I have it to where it will pass the smog right now, but would like some input as I have not used WB's, A/F gauge before this. I did not pull the carb to check transfer slots, so not sure where I'm at but it idles good and I still have response from the screws. They are out 1 1/4 right now and I raised my PP a turn. So at idle now my A/F is 14-14.5 and at 2500 RPM, A/F is 15+-. This truck is HD/454 and gets tested at idle and 2500 RPM in CA. I think those #'s are OK to pass, am I right, close? I have ordered more bits to be able to open bypass air in smaller increments if needed. But seems to be working.

So smog aside, just driving the truck it feels good. When I leave the line the A/F is good 14.7, but getting up to speed and cruising in leans out to 16.8-17. Is that OK? When I go into secondary it feels good and A/F goes to 12.8-13, but I would think I would want it a little rich there for towing.?

One of these days I will get out of this state and be able to have some fun with this truck.

Any thoughts? Thanks for your help guys.

[raf2330]

So I didn't do anything else to the carb and just went ahead and took the truck to my smog test guy. The #'s on my A/F gauge matched his and truck passed no problem. So with Cliff's kit, taking care of warping, a lot of tinkering and this new AF gauge/meter I feel confident in keeping this thing running correctly for a long time. Really nice to NOT have it fall on it's face when I mash the pedal and it transitions into the secondaries smoothly. May still need a little more bypass air at idle for more screw control, but my big problems are gone and I may just leave it alone. Thanks for all the help guys.

[Hillbillyenginering]

You asked if your numbers are OK at 16.8/17.
17.2 is stigmatic. Which means it is at maximum efficiency of burning air to fuel. If the numbers rise it goes into lean burn. Cruise and accel numbers are good. As long as you don't see signs of lean burn or experience ping\knock your good. Doesn't get much better than you have.
Your hampered by strick emission standards.
If you pull a long hard grade. Get out and look at the exhaust manifolds and header pipe. If they aren't glowing red your spot on and not going lean.
I worked on natural gas ford 460's. The exhaust glowed red about three feet back for at least a half hour after its run.