Holley float level sight plug holes

[bill dedman]

Originally Posted by BlueOval Ralph

Just use a 3/8ths drill with the bowl up side down. Seems as I remember there was a difference between the 4150 & 4500 bowls. Are the ones you got drilled and tapped on both sides of the fuel inlets? If they are they are 4500 bowls.

Yes, I had to move the inlet to the other side of the carb for the applicatiion, so I just bought two new bowls. One of the new bowls has threads on both sides of the fuel entrance. I guess that's the 4500 bowl...

Thanks for the explanation!

[Harry 6674]

They are supposed to be different heights. At least thats they way Holley makes them.
I believe the secondary is higher than the primary.

[bill dedman]

Thanks for that bit of information! I learn SOMETHING new, every day...

[Ed Wright]

Originally Posted by Harry 6674

They are supposed to be different heights. At least thats they way Holley makes them.
I believe the secondary is higher than the primary.

I always use a 7/16" drill bit as a gauge for the primary (front) and 3/8" for the secondaries.

[bill dedman]

Thanks, Ed; I am sure that's good advice! I'll follow it!!!

[BlueOval Ralph]

If its a square carb like a 750 same pri & sec vent and throttle blade size I make everything same float levels air bleeds and jets same

[bill dedman]

Ralph; it IS a 750... double-pumper with 4-corner idle jets. Going on a high-boost, turbocharged slant 6....

Thanks for the advice!!!


Bill

[BlueOval Ralph]

A good starting point with no Power valve is
Mj 77 or 78
HS bleed .026
Idle bleed .067 or .070
Idle feed rest in metering block .036 to .039
Set idle so blades are just below transfer slot.
At least .070 holes in throttle blades

[Harry 6674]

Originally Posted by bill dedman

Ralph; it IS a 750... double-pumper with 4-corner idle jets. Going on a high-boost, turbocharged slant 6....

Thanks for the advice!!!


Bill

Are you doing the Hanger 18 mods to the carb?