Same issue on a stock 327 with a glide in my fathers 65 impala, ill have to look up if its a 1405 or 1406
I have found that what's said in post #24 and #29 very important in the past with these carbs. I've had good luck with them, once you get them figured out. Seems a lot of people give up before getting them right. Posted from the TJJ App for iPhone & iPad
had one I couldn't tune took it apart found casting flash in idle circuit cleared it and was fine but gave it away bought a holley and never looked back
I just went through my edlebrock carb... I love Holley but reading studying and trying has really helped me out. Plus I have a friend at the tech dept.... The proper jetting and metering for that engine is... Metering rods edlebrock part # 1459 Jets are part # 1426 and 1427.....The 27s at with the secondary, or metering rods.... Float high is 7/16, low is 15/16ths I just did my 350 this way, and she is a whole nother engine. Keep in mind a bog can be caused by many things, from to tight rocker arms, single plane manifold causing low vacuum further excaserbated by a dead punch. Weak coil, wrong plu gap, and the story continues.... The parts I just wrote I used, it worked. My engine... 350 punched .040 alluminum intake (dual plane) headers, mild cam. Automatic trans.... I will still take a Holley anyday, only because its what I am used too, and I always plug the PV. Many people dont agree... Who cares its what I like. A Crisp clean sounding engine makin power.
Not sure why you turned them in a 1/4 turn, but once you achieve max vac on the idle adjustment, that is where you should leave the idle screws...just make sure that the throttle plates are completely closed when you are adjusting them...
Yeah, this thing aint gonna whip us yet......im gonna do the vac at idle (in gear) thing tonight and compensate with the appropriate step up springs. Im not sure about those part nos. in mustang's post. I used the chart in the manual, and had a kit with jets, rods, and springs and bumped the enrichment up one step on the primary and the secondary, only because the plugs were very white. Used the lean drop method on the idle mixture, and it runs good. All the other things mentioned are right on. This aint our first rodeo, just first Edelbrock carb rework. At least they are easy to change with the little cover things. We figured those springs equated to a Holley's power valve. It had the classic accel pump stumble, but after putting in a new one and trying all the settings on the pump, it still didnt run right. The enrichment step we did, actually worked because a light tan on the plugs now. Just gotta get the hesitation out of it.
From what I've learned a 1406 is a tick to big for a stock 327 a 1403 (500cfm) would probably be the better choice. At least it worked for me.
Here's a guy that managed to get the bog out of the 1406 on a 440 and gives added info on a combo for the 383 mopar not sure what size you SBC is.. it is very well written and hopefully may give you some ideas.. I think the larger pump shot is when the rod is in the top position, you mentioned you were on the lowest http://www.cbodydrydock.com/forum_viewtopic.php?6.153771
We have been fighting this 1406 EdelBOG for awhile now. It had the typical off idle bog and after installing a new pump, and using the different adjustment holes with no real improvement, just a little bit better. Well, guess what the trick ended up being.....BENDING the friggin rod a little at a time until it finally would give an instant fuel shot........then I fiddled around with the step up springs, starting with the heavy one, working to the light ones until "waaalaaa", the damn thing goes pretty good from off idle. NOW to figure out the secondary huge "hole" or bog when they kick in..... <!-- / message -->
on my old engine [tired 350]the 1406 worked right out of the box.The ZZ4 that went in has the BOG at any speed.This morning I changed to the orange springs and 73-47 rods.The Bog is gone.I bought the pump squirt kit #1475 but I'll make one change at a time now.
The Jalopy Journal
