Holley vacuum secondary to mechanical secondary conversion trick

This is the Holley carb that I use on my wood gas fueled Chevy 350, it rarely sees gasoline flowing through it but this truck is old school in how to convert your vacuum secondary carb to mechanical secondary

[@nathanhopkins4879]

Love all the content

[@BigBeavrSlayer]

Thanks for watching bud!

[@kittywampusdrums4963]

Haha awesome. My holley is a 2bl on my v6. They are the best hands down.

[@gavinenglish9335]

But there's no accelerator pump on the secondary. Seems like this would cause your motor to fall on its face without the secondary pump providing extra fuel.

[@BigBeavrSlayer]

True there is no accelerator pump. This only activates the rear butterflies which allows fuel pulled through the booster from the back bowl. It does not operate as a double pumper woukd just as a mechanical secondary. The only down side of this is if you don't have a adequate fuel pump you can run out of fuel on a very hard pull as the front bowl fills first so the rear can potentially run dry. But I jave not had that issue with a electric pump and for my purposes of running on woodgas it helps off the line performance massively

[@jkrestorations3679]

so i have the same carb with mechanical choke for my 305, it’ll be going in an S10. do you think this would be a good trick?

[@BigBeavrSlayer]

The truck with doing this is you don’t have a second accelerator pump “double pumper” so you have to rely on engine vacuum to pull the fuel from secondarys it will work but it’s not as effective for a long pull

[@4-gear]

Lol

[@bobfultz1937]

As black as that carb is inside you have a problem with the timing .

[@BigBeavrSlayer]

Haha that's carbon buildup from the alternative fuel I run this truck on. Woodgas gets messy