I don't have PMOs, I have 46 Webers. So I would be using PMO's bowl plug-in vial to set the levels. My understanding is the key is to have them same so that the main circuits' reaction times are nearly as close to each other as possible.
In terms of your current jetting, it sounds consistent with other jetting i've heard of. But do think about changing to the F3 since it shows up as the tube of choice for many people. My reference material doesn't list the F11 as "current" useage so i'm not sure what type of circumstances that tube is used for. F3 is described as two uses:
1. For mixture enrichment at low rpm or during slight acceleration (tube w/out orifices at top)
2. When mixture enrichment for slight accelerations is needed, the fuel reserve in emulsion well must be increased: this is obtained by fitting a tube having small outside dia., orifices located prevailiingly in the lower portion and a larger size air corrector jet to prevent excessive mixture richness at high rpm.
For reference, my 3.0L with race cams is jetted with 36mm venturis, 160 air correctors, 55 idles (too low for me and I plan to change to 60), 200 mains at 4psi. I have to re-check my AF to see where i'm at but I definitely got it richer. Previously I was overly lean 16.0 with my 42mm venturis, 160 air correctors, 55 idles, 200 mains at on 93 octane pump gas. Since I was already high on mains, and didn't have any lower air correctors to cut down the air, I put in the smaller venturis to pull more fuel (via higher incoming velocity).
I also had backed down the fuel pressure to 4 because my instruction from the shop that built/tuned it was to have it at 6 to 6.5 psi. I felt that was way too high based on most everyone I ask- overpressure pushes the floats off the valve and you get excessive fuel and possible overflow. I suspect that high pressure worked at WOT when the mains could suck the fuel out of the wells at a high rate. However at lower rpms I don't think that was good to be running that much pressure.
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Originally Posted by ratpiper71T
If it's the chart I posted does it not suggest that f3 or f26 is the ET for a 2.7?
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You are correct. My mistake. F26 is a choice for "very large main fuel jets" according to one of my text sources. So might not be a good choice in dipso's instance since he's running 135 mains which aren't necessarily considered "very large."
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Originally Posted by RWebb
I agree completely. It makes no sense that when I backed off a tad from 3.5 on my PMO regulator that my PMO carbs ran better. It makes no sense at all...
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I'm just saying that fuel pressure shouldn't be viewed as a tuning tool per se'. Typically it's a set-it-and-forget-it approach and you focus on other variables. Since there's a well of fuel the carbs are feeding off, i'm suprised a slight tweak in pressure would produce the result you had. You sure your pressure reading is correct? If the pressure is errantly high by a good bit, backing it down might have made it agreeable to the carbs?