I just had my 305 swapped out for a 400sbc w/ a Edelbrock carb (don't know what size). I believe its running a little rich. When I start it up I get a puff of smoke and I can smell gas in the exhaust. Also when I get down on it really hard it bogs down on me.

I need some feedback. Is this something I could do myself, or should I seek prof. help. (I'm obviously not a mechanic)

 

Right from Edelbrock, and it works. I use this procedure when I install a performer carb, or my old Carter AFB.

The Edelbrock Performer Series carburetor has conventional Idle Mixture Screws (IMS) that provide a leaner A/F when turned clockwise and richer A/F when turned counter clockwise. The idle air flow is controlled by a conventional screw that opens the Primary Throttles. The following procedure should be used to set the idle mixture and speeds.

1. Fully warm engine and ensure choke is fully open.

2. Air cleaner in place.

3. Set desired speed with the air screw.

4. Adjust the IMS on ONE side to get the maximum possible RPM. Do not go rich beyond the maximum speed point.

5. If the above changed the idle speed more than 40 RPM, then readjust the speed.

6. Adjust the side OPPOSITE of that in Step 4 to get maximum RPM.

7. Reset the speed.

8. Carefully trim each IMS to again get the maximum idle RPM.

9. Go leaner just enough to get a 20 RPM drop in speed.

10. Reset the speed to the desired RPM.

11. This is a Lean-Best Idle Set. Setting richer than this will not improve idle quality or performance, but could tend to foul plugs.

Actually, you should read this whole tuning guide: EPS Carb Manual: Section 2 Tuning Procedures

The model number of the carb will be stamped on one of the bolt-down flanges.

 

Thanx man, I'll read the article.

 

Bogging when going wide open quickly on an Edelbrock is often the accelerator pump setting. Move the rod to the hole CLOSEST to the fulcrum point. That gives you the most accelerator pump shot. Just about every Edlebrock on a performance engine sees improvement with this change. It may not cure it, but it often makes it much better. I've never seen or heard of an Eddy carb it made run worse.

 

I have my pump shot at max and it still bogs sometimes. Sometimes it makes a pop noise and then dies. I have a big cam and the vacuum is low, so I put the lightest step up springs in to help and it did help at first, but doesnt seem to now. I wish i was better with carbs.

In the higher RPM's it runs great.

 

Maybe a different size metering rod?