Main Air Bleed Confusion

[leeklm]

Just ordered a kit for a 7042264, and am a little confused about Airhorn and Body Main Bleeds.

In the book, "First Recipe" notes to size both main bleeds to .070, unless it is a single Main Air Bleed carb.  Looking at these pics, the first is showing the Main Bleeds in the body.  Is the second pic (drill bit inserted) considered the Air Horn Main Air Bleeds??

If yes, does a single main air bleed carb just not have the holes in the air horn? 

Thanks!

[leeklm]

Sorry, one more question... I have the power piston spring kit; what are the ratings on the 4 colored springs?  With the above carb & "recipe 1", what spring is suggested for a mild Pontiac 400 (manual trans) that is reading approx 17-18 vacuum at idle?  Trying to avoid pulling the airhorn off too many times 

Thanks again!

[Cliff Ruggles]

Single main airbleed carburetors are much different than what you are working with.  They have one pair of main airbleeds in the airhorn, coming in at an angle with two small brass tubes in the ends that extend out into the incoming air stream.

17" is plenty of vacuum for any spring in the kit.  I would use one of the stronger springs, the order from lowest to highest is Orange, Light Blue (plain color in some kits), Green, Dark Blue.....Cliff