I have a 350 with an edelbroke carb.
Trying to get it to pass emissions.
The cats were installed today.

Allowed: CO% - 1.2, HC - 220
First Test: CO% - 5.3, HC - 452

I adjusted the fuel mixture screws on the carb and got the numbers to:
Second Test: CO% 3.18 at 2500, CO% 0.00 at idle. and HC down to 120.8. HC is passing and CO is passing at idle, its at 2500 that I have an issue.

I am very close. I just need to lean the carb out at 2500 rpms.
The current need is a 7047. Im thinking I need to increase the needle up
one size. Do you guys agree?

I set the fuel mixture screws at 1 turn out. They were 4.5 turns out.
I didnt do that. Was that way when I bought it. Timming is about 14 degrees advanced at idle.

 

So... I couldn't find any metering rods at the local parts store and the race shop isn't open. I did find a spring kit. I went two springs lighter. Truck still runs nice. Hopefully, that will lean it out enough to pass.

 

I've never had much luck tuning an Edelbrock carb. I bought the offroad tuning kit and tried all sorts of things to get mine running right, but never was successful. Finally gave up and replaced it. Hope you do better!

 

drop the edelbrock and get a holley or barry grant!

 

Don't get a Barry Grant for anything! They just closed their doors, gone bankrupt.
http://www.dragzine.com/news/barry-g...es-operations/

 

really hadn't heard that! thx for the info.

 

that does suck though! well at least he can still go with a holley.

 

Yes, it does suck. I hate to see an American company started from nothing go under. They actually went chapter 11 two years ago, but finally gave in and filed chapter 7 and that means immediate closure. Sad, as he even lost his personal home, and everything he'd worked for over the years. I'm not sure I could handle such a great personal loss.

 

Ya it is hard to see stuff like that happen. I know my uncle used to run his carbs on his super gas Vega back in the early 90's.

 

I would get a A/F gauge. Tune it until that right. Get O% at idle doen't seem right. That means it not running? Right. Think about it this way. At 2500 your off the idle circuit and into the main jets, how that works on an Eddy I'm not sure. Maybe play with the timing to get a better burn. Horsepower is always hocking E3 plugs that may clean it up. IDK I never put much thought into unconventional plugs. Anyhow you need to lean the main circuit.

You didn't say what carb you have? What metering rod and jet are in it? I'm going to guess its a 1406, elec. choke 600 cfm. If so I'd try the stock jet 1426 (.095") with a 1456 (.073" x .047") metering rod.


The way I read the chart the one you picked fattens it up in cruise and leans it when the secondaries come in. The way I see it the one I picked leans it both ways. Plus it can be done with the tuning kit, which gives you more options for less money. Still I would get a gauge.