Understood. Not saying you are wrong but I’ve never seen or heard of a factory EFI setup that ran so rich in startup that it would foul spark plugs. When the EFI vehicle is started up it’s on the open loop fuel trim, which means it gives a pre determined amount of fuel without any input from the 02 sensor. Then once the temps get up there it changes to an closed loop fuel trim taking input from the 02 sensor to reduce emissions and improve fuel mileage. So yes it runs rich until it’s warm but nothing as extreme as a carb... The only time I saw a EFI vehicle foul plugs was when the fuel pressure regulator went on a TBI setup and it went to open loop full time. It went from 15 mpg to 10 mpg and fouled the plugs within a few tanks of gas....
the fuel map is still predetermined by the cts. I've seen them fail both ways- full cold at -45°f which dumps fuel so quick that the car won't run at all and fouls the plug within a 20 seconds of cranking, and also get stuck in the warm position and not be rich enough to start.. EFI also has a cold high idle speed. I can't say if EFI is better or worse but I wouldn't label a choke as "extreme". they are very carefully calibrated to be closed the minimum amount of time to start the car as determined by the pulloff that coincides with a specific high idle speed. on any kind of rev the choke goes wide open. an engine still needs a fat mixture to start and idle when its cold. efi hasn't changed that. next time you start your car in cold weather, smell the exhaust and you'll smell the richness. it would be interesting to compare AFRs between with a cold start between a carb and efi. I'm sure the efi would be cleaner but I bet not by much. sorry it's pet peeve of mine. I've seen and heard folks say countless times that efi eliminates the rich running choke starts.. well, it doesn't....
Heat sink bung. Why? https://www.ebay.com/itm/HEAT-SINK-...997511?hash=item3b219cd807:g:7yEAAOSwkitb4J7m This is what most of the ebay bungs look like. https://www.ebay.com/itm/EXHAUST-O2...rand=Unbranded&_trksid=p2047675.c101195.m1851 I like the stainless bung better than the steel one provided by AEM... If AEM bung is SS excuse me..
Two pumps of the gas and set that choke and I could start my cold motor up with points mind you and it would go to 1200 rpm and sit there. Kick it down a notch and keep on running, EFI is for new cars. I would never do it just something else to go wrong and electrical crap takes a crap Way before mechanical does. I know I run a printing press Full of electronics and that crap is always giving trouble The old mechanical machines run forever. We have a Heidelberg Die cutter that is 60 yrs old still goes.
