Question for those running a 500 cfm Edelbrock

[Furiousvip]

Going to bolt on an 500 cfm Edelbrock 1801 AVS. I'm curious as to what combination of jets and metering rods yielded you the best overall performance?
Engine is not stock...Head Shaved, oversized valves, cam, headers, Clifford intake.
Thanks in advance for the info

 

[kesteb]

I used the 7.5 metering rod springs and 1 step leaner. I also ran into the problem that the stock fuel pump couldn't keep the fuel bowls filled. I fixed that problem with a napa 426/440 replacement fuel pump and a 3/8" return style fuel system.

 

[Dizzydean]

I don't remember the numbers but I used the manual that came with it and dropped rods and jets down one step. Ran great. I had the same block work and was running the Aussie long ram.

 

[Hipo65]

The ONLY way to know is to tune via wide band o2 gauge man! Every car is diffrent mine runs twice as good as it did with the stock afb (only reason I didn't tune the stock afb is lack of 3 step metering rods ava now days) I used smaller jets in rear (alot smaller actually) stock jets up front. Metering rod's ended up & 52x71. Also enlarged idle circuit tube .002 end result's are 14.7-15.0 cruise, 12.2-12.0 wot & 12.5 ish idle in gear. It is a very snappy 273. Get a wide band & be very amazed my friend!

 

[Furiousvip]

The ONLY way to know is to tune via wide band o2 gauge man! Every car is diffrent mine runs twice as good as it did with the stock afb (only reason I didn't tune the stock afb is lack of 3 step metering rods ava now days) I used smaller jets in rear (alot smaller actually) stock jets up front. Metering rod's ended up & 52x71. Also enlarged idle circuit tube .002 end result's are 14.7-15.0 cruise, 12.2-12.0 wot & 12.5 ish idle in gear. It is a very snappy 273. Get a wide band & be very amazed my friend!

Agreed...I assumed the carb is a little rich out of the box for this application...just looking for confirmation and a baseline tune...then fine tune from there. :thumblef:

 

[pishta]

a 500 on a 6, would start to jet leaner and keep going until you find happiness. Also the AVS spring would probably need to be adjusted to open the secondaries without a bog, ie. tighten to cure a bog. Thats alot of carb on a slant unless you tune it.

 

[the wall]

a 500 avs is almost self adjusting the valve on the secondary side wont open till the engine pulls enough air to open it the factory jetting will be close for wide open throttle. the tuning issue will be for snapping the throttle hesitations things like that. use lots of initial timing will help.leaner jetting doesn't make the carb smaller it makes leaner. usally carbs that are larger then whats considered to be normal use run lean at lower rpms because of low air speed causing poor mixing but when engine speed climbs the air speed picks up to exceptable speeds and fixes the problem. basically i wouldnt do much till you have good feedback like driveabilty and reading plugs that is of course that the carb is starting off a stock piece