Need jetting help!

[Gerry Holmes]

i've just bolted an Edelbrock 1411-750CFM with electric choke onto the original intake of my 1969 "N" code 330 H.P. 383. The motor is stock, with about 80,000 miles on it, compression of 145 all around, and has all its oil changes (clean inside). What i'd like to know is what internal changes, if any, that i should make (jetting, metering rods, springs etc.) and what i should expect for horsepower increase. Thanks Gerry

 

[Optik]

Unless you have an A/F meter installed, you'll probably be tuning to the plug readings and seat-of-the-pants driving feel. I have read repeated accounts of these carbs being so lean-calibrated that it's hard to get a good tune with them. The online manual from edelbrock has a tuning chart that would be a good place to begin.

 

[Gerry Holmes]

thanks Optik, i downloaded the manual, it's quite detailed. my thoughts were that someone might have gone the route that i have, and have the exact info. thanks again Gerry

 

[Darter6]

Try your Eddy as is. If you find that it has a stumble or wants to die with slight off idle throttle then it is too lean.Sounds like this is a street car so you won't need much of a change, a little goes a long way.Example,, On my engine the pipes were black,too rich.Changed metering rods from 65x52(thousands) to 74x47.Way too lean, car wouldn't pull out off idle and stall.Went to 70x47 still to lean,driveablity was better but had a flat spot with slight throttle off idle.Also had a surge at crusing speed 35-45 mph. Installed 68x52 rods, all problems solved,pipes cleared of soot. So a change of 3 thousands can make a big difference. Out of the dozen or so Eddy's installed most worked fine out of the box, but just a metering rod change can make a difference.
Hope this helps.

 

[Gerry Holmes]

thanks Darter6, in fact yesterday i did just that, and because the kickdown was in a different location, it shifted to soon, and flooring the gas gave slow acceleration, so i readjusted the shift speeds up, and now it goes like hell! i did get a slight pop from the carb when doing maybe 30 mph then flooring it, but off the line it's a bullet! thanks Gerry

 

[Darter6]

Good to hear.!