ICEMAN59

I did a search and didn't come up with anything usefull to me. I'm a definate novis at tunning carbs. The car takes off great but then boggs down even though I'm at full throttle. It even dies sometimes. I changed my air filter and I am getting more air now. It acts like it's flooding, sometimes when I turn it off it will deisel out. Is there anywhere I can get a good book on how to tune a carb like this one.

Thanks in advane,
Keith

MsVetteMan

Do you have the EB carb book that came with it? If not, go to summit's website and click on your carb, there is a pdf you can download with all of the info. EDIT....HERE IT IS......LINK....http://www.edelbrock.com/automotive/eps_intro.html

Good luck....I'm dealing with similar issues.....

Ak. Mal

Sounds like we are dealing with similar issues.

http://forums.corvetteforum.com/show...post1550527550

Let me know if you figure anything out. I'm trying to read that Edelbrock tuning guide, but it just seems to be over my head. I was hoping for something like "Turn screw A until you get smooth idle". Too bad it isn't that simple.

BigBlockk

How long does it take it to bog down on full throttle starts? If it is under a second the accelerator pump would be a good place to start looking. If it is like 3 seconds it may be the secondaries need some attention. If it is 7 or 8 seconds it may be a fuel delivery problem (fuel pump). Does it rattle (pre ignition) when it does this? A heavy bog on hard acceleration is a classic lean condition. Does the engine surge at cruising speeds?

Dieseling can be caused by a lean idle or retarded timing. Try advancing the timing 4 or 5 degrees. This should cause the idle to increase. Reset the idle back down with the idle speed adjustment on the carburetor. The dieseling shouldn't be as bad as it was. You may want to try opening the idle mixture screws a little. Record the number of turns that the idle mixture screws are open before you do this.

What do the plugs look like? White or very light tan means lean, black sooty means rich. Is the heat range correct?

BigBlockk

Later.....

AlwaysWave

The car takes off great but then boggs down even though I'm at full throttle. It even dies sometimes.
Fuel delivery, maybe to light at WOT, needles not seating properly?

I changed my air filter and I am getting more air now. It acts like it's flooding, sometimes when I turn it off it will deisel out.
Same as above, maybe retared timing too?

Bear in mind two things noted from the Performer version of these carbs.
1-Edelbrock tells you to check the needles and seats to make sure they engage properly.
2-These carbs overcome the needles with more than 6 psi fuel pressure at the low end and need 2 1/2 psi at WOT.