i got a 650 thunder series edelborck carb. it runs fine idle and feathering the throttle but when i floor it, the carb bogs done and dies. thats just in my garage idling. when i drive it, it falls on its face then picks up after about 3-4 secs. ive tried lengthing the accelerator pump rod, and put bigger jets in the secondaries. i dont know much at all about carbs lol. id really apprecaite if someone could give me some insight.
the engine is a 355, stock heads ported, and a lt4 hotcam with 1.6 roller rockers. distributor is set at about 12* base

 

I had nothing but trouble out of my Edelbrock and finally gave up to buy a Holley.

Have you tried adjusting the mixture screws? If they are set right then open the top and check the size of the main jets. Look at the Edelbrock website for the manual for your carburetor and then verify that the jets that are in it are the right ones. In the same manual they will also have tuning instructions to help you get the motor running right.

 

ill try that. i bought an edelborck before and it ran great out of the box. figured id try it again and now im having problems. didnt want to go with a holley, cause from what i was told a holley was more of a strip carb where as the edelbrock was more street

 

ok so i bumped the pressure up on my regulator and it does a lot better now. it now longer dies when you floor it, but it still bogs down and hesitates a lil.

 

How much pressure are you running?

 

That's what I heard too, though I heard more that Edelbrock's were more for MPG than power and that Holley was the other way around. But after putting the Holley on I'm still getting more power and MPG than I did with the Edelbrock. I can't wait for the jets and the power valve to show up monday or tuesday so that I can tune this Holley and hopefully get higher numbers on both power and MPG.

 

i think my fuel gauge my be bad, it was sitting around 5 and i bumped it up to 6 psi

 

Did you do anything to set it up, or did you just bolt it on and expect it to work?

 

i havent done much tunning, it says to turn the screws untill you see a 20 rpm drop. i cant tell a difference at all when turning them. can i use a multimeter on the tach output to read rpms accurately?

 

You can, but you have to be sure that you have the type that will allow you to read frequency. My Fluke 87 V has that option but I'm not really sure how many others have it.

 

i have a fluke meter but it doesnt measure frequency. is there any other way? using the tach in my car i cant tell if the rpms are dropping or not

 

Get a tune-up tach at a parts store, or a timing light with a tach function built-in.

 

Which fluke is it? Unless you have a low-end version it should be able to do it. If you really don't have that option on yours (I had to find the manual on mine), then you'll have to get some sort of digital tach, either integrated into a timing light or not, so that you can see that little of a drop. If you find your manual and do find you can read frequency you'll have to do the math to find the rpm.

 

i have fluke model 73

 

The 73 is pretty basic, no period/frequency measurement.

 

Yeah, I just looked it up and saw that. You'll have to go to a digital tach of some sort.

How good are you with electronics? I might have a solution for you.

 

im ok with electronics, what do you have in mind?

 

PM me then