2.4E with e cams and 2.2 E pistons and webers, need WEBER HELP

[marlinaness]

I have a 2.7 case with 2.2E pistons and cams, giving me about 9.5 compression 2.4 E engine. It has headers, M&K muffler, and O2 bungs on each header so I can take AFR readings with an LM2.

I started with the info below based on a similar build I did in the 90s with Webers from you and the following:

F.S. 911 weber 40 IDA's
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The engine was rebuilt with new piston rings etc, so I did this during the 20 min breakin meaning I ran at higher RPMs and did not check the idle, didn't really check the balance except side to side, used the LM2 to see how they were doing.

32 venturies
135 main jet
55 idle jet
180 air correction
F26 emulsion tubes

The AFR was lean around 16-18 at 3k-4k. There was a lot of backfiring out the carbs, popping, etc. This did not make sense based on all the previous documentation I had read. Nevertheless, I changed to

32 145 55 180 F26 and was still around 15 or so on the AFR from 3k-4k

I had spare 30s, I didn't have bigger main jets, so to reduce the lean condition, I naivelly changed to

30 145 55 180 F26. AFR was 13-15, most popping and snapping gone but then briefly took the engine down to idle and it was 16-18 AFR, way too lean and would not run at idle. This only lasted a few seconds.

I then tried
30 145 60 180 F26.

this was improved, but still too lean at idle and the engine died.

I know I have to get the idle fixed and have to get rid of the lean condition to get the air flow, balancing and idling correct. What do you recommend to fix the idle lean condition: increasing idle jet and by how much or reducing the air correction and by how much or both? I also have read F3s are better than F26. Should I go back to 32s and try 70s or 80s and reduce to 170s, and try F3s? I do have 170s and F3s, but nothing larger on the idle jets. I need to get this thing idling first before I can do much else.

I am also getting the distributor rebuilt by Barry Hershon as soon as I contact him. I had to manually change it to get enough full advance and had to change to 0 advance for idle.

[roblav]

1) Get the ignition fixed first. At least 35 degrees BTDC at 3500 RPM and above.
2) Did you check and adjust float level?
3) Looks like you are using IDT carbs... progression might be different than IDA.