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Can Opeler
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Just updating my current tune in this thread. Not much has changed. I went to shorter air horns and found out I was losing a ton of air flow at high rpm. My main circuit went from a 145 to a 160 to compensate. I also raised my fuel level (from top of the jet plate to the fuel level in the emulsion tube well while running with main jets removed) it’s a bit above 25mm now.
I went back to f8 idles but I’ll probably bounce back to f2s for better fuel efficiency on the highway. F2 run leaner between 3000-4000 rpm cruise than f8s but slightly hurt the smoothness of transition to the main circuit which is annoying when going over hills on the highway where the tiniest extra throttle puts you in the main circuit.
Oh and I also made my air jets even smaller to help the fuel level raise in the “emulsion tubes” a little earlier. This was just a fine fine tuning measure to force the main circuit to take over a little earlier to keep my AFR around 11.8 where I have come to like it. A tad richer than 12.5 gives me more margin to avoid going lean and the car seems happier there.

2.0L GT
32mm chokes
70 pump 00 exhaust
50f8 idles (or 55F2 depending on mood)
160 main Jet
~100 air corrector (soldered and drilled)
Emulsion tube replacements For Sale: VP Main Circuit Tubes for Weber DCOE Sidedraft Carburetors w/ 30to32mm chokes | Webstore I’m using the old version of these. I bought these new ones but haven’t tried them yet. The old ones are fantastic.
Notes: I won’t ever improve on this tune without going to fuel injection. I’m done. I have never driven ANY classic car that accelerates and cruises this nicely. Gas mileage is atrocious lol.

stock high comp 1.9L
Choke 30mm
Mains 130 or 135 can’t remember
Airs ~130 soldered and drilled
Idle 50f2
Accelerator pump 60, 00 exhaust
F16 emulsions.
Notes: runs good. I haven’t touched it for awhile and I don’t rev the heck out of it like my other car. This is a good cruising tune. The mains are under jetted for less fuel consumption.
141 - 142 of 142 Posts