Trouble with dual 40

Engine, Transmission and related drivetrain.
Post Reply
russaroll
Posts: 61
Joined: 04 Aug 2013 17:18
Location: Santa Maria, CA

Trouble with dual 40

Post by russaroll »

I was running a single weber 40, it ran good. I bought another 40,(to run dual carbs) jet it the same. Now the car runs good in the driveway but it's bogging under load. Any tips?

I tried more advance and no vacuum advance.
The older carb was tapped for vacuum advance so I was using it.
Think I might try smaller idle jets.
User avatar
abisel
Posts: 221
Joined: 29 May 2014 14:30
Location: St. Charles, Missouri

Re: Trouble with dual 40

Post by abisel »

I would suggest:
remove and plug the vacuum advance on the one carb.
I am not running any vacuum advance, only the mechanical advance in the distributor which is the electronic distributor.
I am not running any engine block ventilation into the Cannon manifold.
go to this URL and try the jetting I used: viewtopic.php?f=30&t=28635
I do have a WebCam mild race cam, so my ignition timing is 12-15 BTDC. But you may want to try to advance the timing.

My L20B runs a bit rough/rich at idle, but runs fine once off idle which I set at 1K. Could be the cam giving the rough idle symptom. I sill have a very little hesitation when I stomp on the gas pedal, but I don't do that very often anyway, so I can live with it.
russaroll
Posts: 61
Joined: 04 Aug 2013 17:18
Location: Santa Maria, CA

Re: Trouble with dual 40

Post by russaroll »

Thanks. I'll give it a read.
Post Reply