zetec7 wrote:
Okay - the point where the remaining stumble is occurring is right where the carbs come off the idle circuit & onto the mains. The "idle circuit" name is a bit of a misnomer, as it covers everything from dead idle to 3000-3500 rpm - the vast majority of running with DCOE's is on the idle circuit.
If it's running okay below that 3000-3500 rpm mark, you can ignore the idle circuit and just concentrate on the far simpler mains circuit. That's GOOD news!
You need to find out if it's lean or rich when it comes onto the mains. If you have access to a ColorTune, exhaust gas analyzer, or wideband O2 analyzer, that will make it easy. If not, it's back to the old tried & true shadetree mechanic's test. Clean the plugs so they're spotless, run the car hard, at the point where it's stumbling for a minute, then pull over and check the plugs again. If they're really pale grey and dusty, the mains are too lean, and if they're black & sooty, the mains are too rich.
I have a Gunsen Gastester which I've used in the past for FI calibration. Although I've generally used it to set idle mixture, I'll have to make some mods to use it under load.
http://www.gunson.co.uk/product/G4125/I've checked the plugs in the past and the engine is indeed running lean. I see that a Weber "jet' kit is reasonably cheap, so I'll probably buy a set and go from there.....I've opened the carbs and noted my baseline:
Weber 40DCOE #151
Idle Jet: .45mm / F9
Main Jet: 1.15mm
Main Air Bleed: 2.0mm
Emulsion Tube: F11
Accel Pump Jet: .40mm
Venturi: 30mm
Can you recommend a shop in the Lower Mainland that stocks DCOE parts?
Cheers.