[1meanchevy]

Quick question, I recently purchased a 4150 with mechanical secondaries(pn# 4777-4) , and I am about to install it but I noticed the secondary throttle plates don't open all the way when the primaries are at WOT. They open to about 80 to 85% almost 90 but not quite, is there an adjustment I can do on the lever or something?? I was sitting there looking at the lever and I can't figure out how to adjust the secondary throttle without touching the primaries. Kinda new to this, any info would help.

 

[The Big Al]

What you have is stock. You can remove the link arm and bend it.

Be warned! you could hurt the performance of the carb. When blades are open at 100% (90°) in most cases it will flow less air. Because of reversion of the throttle shaft. It can also cause a lean condition weakening the low pressure signal for the booster.

your best leaving the carb alone.



AL

 

[1meanchevy]

What you have is stock. You can remove the link arm and bend it.

Be warned! you could hurt the performance of the carb. When blades are open at 100% (90°) in most cases it will flow less air. Because of reversion of the throttle shaft. It can also cause a lean condition weakening the low pressure signal for the booster.

your best leaving the carb alone.



AL

I only as Al, becasue the Holley book says (I know a book) "make sure all throttle plates completely open at WOT, both secondary and primary" I was thinking there was a reason why it wasn't opening, just wanted to follow the instructions.