Weber Jetting

[pacarguy]

My car has been popping a bit on deceleration. After cleaning the idle circuits it was no better. Exhaust leaks have been ruled out. My mechanic recommended installing larger idle jets. He said the quality of the 93 octane is not was it was a few years ago and putting in a larger jet helps. Before I have him do the work, I was wondering what others are running on their 2.0L cars with Webers.

[Mr9146]

Your mechanic is right about the fuel. It's not what it used to be and jetting combos that worked in the past will probably not work so well today. We just went through a similar issue on a 2.2T with a set of BRAND NEW Webbers; more fuel was the solution to the problem.

[John Fusco]

I was running [30 venturis] 125 mains with 55 idle jets and switched to PMO recomended 130/50 (both set ups with 180 airs and 110 idle airs):

The car ran worse with the change.

Left the 130's in and went back to 50 on the idle jets.

Car runs great.

[t6dpilot]

I have been struggling with a cutout issue that we have solved. Long story that I won't get into in this thread, but we did a lot of investigation with the ignition and fuel delivery setup. I have a 2.2S spec motor with Solex cams (that I just found out about I was told they were S cams) and Weber 40IDA. The setup was with 135 mains, F3 emulsion tubes, 180 air correction jets, 52 idle jets, and 32mm venturis. The car ran really good to the "untrained eye" other than the cutout issue. When we really dug into the fuel delivery system and measured the AFR, we found some slight anomolies. We settled on 130 mains and 55 idle jets, which is what the original setup should be. Everything else remained the same. Hope this helps.

[Fritz A. Ficke]

factory setting I belive for 67 2.0L S with 40IDA is
32 venture
135 main
55 idle 170 Air C.
f-26 E. tubes
Which I found ran great, a little rich in Tucson area at 3000 Ft.
Really very nice at sea level.
Now I have in the same 2.0l S engine
34 venture
145 main
60 idle
180 Air c
f-3 E-tubes Which makes it a little harder right off idle (lower end power is less) but now will make power all the way to 7,500 RPM.
I have also found that when the gas is over 4 mounths old the car will pop and and have lean miss fires, and if you chase jetting with gas that is a few months old you will go in circles. Webbers need fresh gas. I insist on tank fulls of fresh gas through an engine before I will play with jetts.
Good luck, Fritz

[911pcars]

"....I insist on tank fulls of fresh gas through an engine before I will play with jetts."

Fritz,
I try to insist as well, but all I can do is talk to my wallet. "Wallet, please release a C note to fill my tank." This plea is often ignored, so I must rely on $20 of the latest bubbly to tune, which is more than necessary to fill float bowls, carb passages and jet orifices... for a short time.

Sherwood

[Fritz A. Ficke]

Sherwood, I do the insisting most when it is not my money I can charge to burn the gas out but usally wallets prefer that the owner does it.
Fritz

[Grover]

I think a lot of where you live and sea level have a lot to do with setup for your carbs. I live in the midwest in Micigan, on My 1967 2.0Ls the best gas for the street I have been using BP Amico 93.The fuel rating is different then when the cars were new and 93 is the same as the old system of 96 octane with lead, they say? I have 40IDA with good throttle plates(important) I have played with all kinds of setting and venturis. I keep going back to stock size venturis 32mm,130main,180 air, idle55 use K&N air filters with 31/32 degree timing and NKG plugs or old Champion N2G, N3G plugs. I have had better luck with these plugs. The bigest thing that helps is getting the hotest spark to plugs. When I used MSD system it was a little better at idle. When I change to Electromotive 3 coil system with out distributor it was much improved at idle and runs much better at high end. The best thing is to run leaded racing fuel and it then really runs good. Of course that is not very pratcical.