[updated:LAST EDITED ON 18-Aug-02 AT 03:30 PM (EST)]I just stuck a 1407 Edel carb (750 cfm)atop my new 410's Performer intake and Edel 427 heads. It replaces a 1850 Holley (600 cfm) that I couldn't tune to my satisfaction from being continuously rich, but it did run like a gazelle up to and past 5000 rpm.
Now I have very lively performance from the 1407 up to about 36-3700 rpm, but as soon as I get into the secondaries, it goes flat, surges, and really struggles on up to about 4500 max. I have gone 3 stages rich on the secondary jets with no apparent change. My Stoich meter still reads rich throughout, with sooty exhausts, in spite of various jet and rod changes(and new O2 sensor), and I'm wondering if I can believe it totally. I have a 14"x5" cartridge air filter so it should be getting plenty of air. I'm also running a Pertronix Ignitor II with 14 degrees initial timing triggering a Blaster 2 coil, and the total advance is about 36-37 degrees. I've tried the vacuum advance on both manifold and ported with no apparent effect.
If it hadn't revved so much better with the Holley, I would suspect some problem with the fuel supply, but that doesn't seem likely?!?
I jumped at the Edelbrock largely based on the premise that it is "so much easier" to tune, but it's starting to be a real disappointment. Can anyone clue me in on what else I might ought to look at before I swallow my pride and stick the Holley back on and fight it some more?

 

Get rid of that Edelbrock carb. There is a popular misconception that the E-bok carb is the same thing as the old Carter AFB. It ain't. It may look the same, but there are frequently problems. Get an old Carter AFB or go back to the Holley. As I understand it, when Carter was purchased by someone else, some of the guys working there didn't like the benefits/pay package they were getting from the new owners, if they kept their job at all. So some of the tooling 'left' the plant. Some of it stayed but was worn out or damaged or vandalized. This is the tooling that your E-boks carbs are now being built on. At the shop where I'm working we have had all kinds of problems with them. You can change jets and rods all you want, but if the internal passages are misaligned or not drilled to the proper depth, it won't make any differance. You might be able to send it back to Edelbrock and see if they can provide a better one. DF

 

how much fuel pressure do you have? is your float adjusted properly?

 

Actually, I traded the 1407 (750 cfm) for a 1405 (600) today, and it seems like all the problems went away right out of the box without any adjustments other than the idle!! I'm not sure if the size was the problem, or just the particular carb, or maybe the combination of the 750 on the Performer intake, but it's running very well now.
I had spent so much time dinking with jets and rods, and checking and re-checking the float level, fuel supply, etc., etc., that I was pretty frustrated, and having some major self-doubts.
I've still got to do some road tuning to see if I can get the Stoich meter into the range that it's supposed to be, but it's so much more responsive to even tuning the idle that I'm pretty confident that we're on the way!
Have you had any experience with a Stoich meter and how reliable the readings are? I'm more than a little concerned about possibly hurting the engine by tuning too lean based on the Stoich, but haven't heard any reports like that.
Thanks for getting back to me.
Steve