38/38 Weber, progressive?

[sb_hbackDX]

Hello all...i just got a 38 Weber and im not sure if I should try this but I was gonna try to make it progressive. Already its synco. due to the two 90 degree cut looking gears that mesh together which open the two paddles. Well I noticed that i can just unscrew them so I was thinking about moving them so that by the time the primary is open almost 2/3 of the way the other begins to open. Of course I might have to switch out the gear to allow for more movement(need more teeth) and maybe rejet/ adjust the mixture but I think its possible...what do yall think ? Keep in mind that i just woke up with this idea in my head so yea it may sound crazy and probably will tomorrow haha.

[A20A1]

You'll need to make one gear larger and one smaller... that right there will take some calculation. Or some trial and error.

Not only that but simply having it on two different sized gears is not enough... you need to figure out where the secondary will begin to open.

It may be best to make it vacuum secondary... that will be a lot easier.
Also since vacuum is a good measure of engine demand it might be better in your case. When vacuum drops as the primary opens the secondary will begin to open as it opens vacuum drops more, it opens fully.

It just depends how you set up the spring inside the vacuum secondary diaphragm... and the linkage radius I suppose... since it gives the diaphragm spring it's mechanical advantage.

There should be a means to make sure that when the primary closes... it forces the secondary to close as well... the srping sould overpower the vacuum advance spring to ensure that the throttle closes and you don't end up with a runaway car.

Seriously though... vaccum secondary is a good way to go.

the 38 weber utilizes and dual squirt accelerator pump... this pump jet may have to be swapped for a 32/36 jet... with a single hole squirting into the primary. This will keep the fuel from going into the secondary barrel where the fuel might not break up well and might get caught up on the secondary throttle plate causing a delay.

[sb_hbackDX]

Kool thanks for the relpy. Aside from finding some way to attach a vacuum secondary to the secondary do you think using the jets from the 32/36 will affect its performance? Them being a single instead of a double squrt? Maybe I could increase the fuel psi to counteract that...

[A20A1]

A large 32/36 accel pump jet is the only 32/36 jet you might use on the 38WEBER... I think a 60 should be enough, maybe, maybe a 65. The rest of the fuel demand can be made up with a properly sized 38WEBER idle jet...