Edelbrock 750 lean condition

[6t4polara]

Posting for a friend has carb on a 440 mild cam and seems to run lean.
Anyone else have this problem and was it resolved by increasing jet sizes.
If you had this problem what resolved the issue?


Thanks,

 

[moes]

He might get away with just a metering rods change, too. He should have the Edelbrock chart that helps with installing the correct metering rods for different situations. An air fuel ratio gauge is a great tool, it allows you to see when it goes lean or rich.

 

[dvw]

Seldom are Eddy 750's lean. Usually a tad rich. What makes you think it's lean?
Doug

 

[WileERobby]

Seldom are Eddy 750's lean. Usually a tad rich. What makes you think it's lean?
Doug

Precisely. Plugs reading lean ? AF meter reading ? please elaborate

 

[Darter6]

metering rods change,

We usually do a metering rod change for driveability such as a mid range surge.Most times 2 sizes smaller to cure the surge.
As dvw stated It may be a rich problem. I had that with a Edelbrock and kept going richer and it got worse.
Engine started to break up at 4000 and above rpm.
Ended up going 1 jet size smaller in both the primary and secondary.
I have no AF meter and mainly check plugs(tho with today's gas it may not tell a true story)
Old school trial and error for me. One question is it a manual choke or electric ? The calibration is usually leaner on the electric choke models from the Edelbrock factory.

 

[Rusty knuckles]

Get a hold of the right calibration chart for your carb. I'm assuming a 1407 as thats what mine is. Stock out of the box is #1 on the chart. Each number corresponds to a specific metering rod and jet combo. You can see there is a power and cruise mode. You didn't specify why or when you think you're lean. The chart works that if you want more fuel in power mode (hard acceleration) pick a number more to the right but same or close vertically to your current setting. If you need it in cruise mode (steady state driving) pick a number that's higher vertically but same or close left to right to your current setting. Obviously you can adjust both at the same time by picking numbers in a diagonal fashion. Generally try to stay in the gray band. Very easy to do, fast, and clean to make changes.

 

[Ranger16]

My Eddy 750 was so rich when I got the car it would make your eyes water. Metering rods and jets solved the problem and I picked up a couple of MPG.

 

[dvw]

i ran my 572, 15-1 comp, [email protected] cam race motor with stock front jets and one size up in the rear. Like I said, the factory cal is a little fat.
Doug

 

[6t4polara]

Thank you for your information will pass it along.