Six pack secondary paper clip test?
Yes Pishta you are correct. It's the velocity in the venturi and sometimes there is (or should be) a tube sticking out a little to amplify the signal. It does what Rob say when the carb size is somewhat normal. But it still works if the the carb is small (restrictive) and the manifold vacuum rises with rpm.
To the OP's questions.
Not sure how you had the paperclips. I generally use a twist tie.
First thing I'd want to check is whether they are opening at low throttle high speed cruising, like 60 mph.
The reason I want to know that is for setting and tuning in the primary main jets. If there is fuel air coming in from the secondaries (outboards in your case) then then changes to the primary won't have as much effect as they should.
Here's the hights and coils I measured for some of the Holley vacuum secondary springs.
Originally posted here Vacuum Secondary Diaphragm Springs
there's also an update there showing the short yellow spring (1.5").
Tuner discussing how the cross passages work and more. On the next page he discussing the check ball.
Vacuum Secondary Diaphragm Signal Tube
(If calling a 6-pack a "tri-power" gets your pants in a wad, don't read. I think he does that just to get a rise out of the overly sensitive. LOL)
Yes Pishta you are correct. It's the velocity in the venturi and sometimes there is (or should be) a tube sticking out a little to amplify the signal. It does what Rob say when the carb size is somewhat normal. But it still works if the the carb is small (restrictive) and the manifold vacuum rises with rpm.
To the OP's questions.
Not sure how you had the paperclips. I generally use a twist tie.
First thing I'd want to check is whether they are opening at low throttle high speed cruising, like 60 mph.
The reason I want to know that is for setting and tuning in the primary main jets. If there is fuel air coming in from the secondaries (outboards in your case) then then changes to the primary won't have as much effect as they should.
Here's the hights and coils I measured for some of the Holley vacuum secondary springs.
Originally posted here Vacuum Secondary Diaphragm Springs
there's also an update there showing the short yellow spring (1.5").
Tuner discussing how the cross passages work and more. On the next page he discussing the check ball.
Vacuum Secondary Diaphragm Signal Tube
(If calling a 6-pack a "tri-power" gets your pants in a wad, don't read. I think he does that just to get a rise out of the overly sensitive. LOL)
