AFRs on pump gas
- Thread starter ZephTheChef
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This is on the adapter plate Regal. So it's a 100% stock tune at this point. So like 10 degrees under full load is what it shoots for...I am basically at zero advance after KR. I have the ability to change it though, just haven't since I was shooting for an absolute minimal setup. Maybe I should pull it back 5 degrees across the board and see how that does? I am running about the coldest plugs you can get for these...ngkb8efs. They are non-projected as well, so it shouldn't be an issue with that side of things.
I definitely have found that to be the case on E85 and Methanol. I see guys talking about 10.5:1 and just wonder why. I have had best results with methanol at around 13:1. I usually chicken out and fatten it back up to like 12.2:1 for daily use.
I cannot, due to having to clearance the bypass valve actuator. The lower diaphragm is not sealed now, so the factory boost control setup will not work. It may not matter. I just drained the oil to determine if my tapping noise was getting louder or if it was just my imagination. It is in fact a nice sparkly bronze color. No chunks though, just a lot of sparkle. No sizeable chunks in the filter, but it looks as if this tired old motor couldn't handle the boost. Headed to pick up some nice thick glue to put in there for some more runs...would love it if I could get the knock retard issues worked out before putting a new engine in so I don't put that one at excessive risk.
Looks like my devil-may-care strategy on this build might have been a bit too aggressive.
Looks like my devil-may-care strategy on this build might have been a bit too aggressive.
Unless ur WBO2 can be re-curved for different fuels, I would use Lambda as the guide. The 10% ethanol we have here in Chicago has a stoich of 14.2 not 14.7 but Lambda will always be 1 for stoich regardless of fuel. So whereas I would shoot for 13.0AFR WOT w pure gas, my ZT-2 WB would indicate 12.6 for 10%.
It is definitely toast. It will be alright though, I have a spare drivetrain.
I turned up the fuel pressure hammered it hard on the way home. It is rattling very loud now. But the good news is, with 75psi base fuel pressure on an otherwise stock tune, I saw 0 KR, so I do think being lean was the issue. That was at 11 degrees timing at WOT. It made 34.7 lb/min on the MAF at 4800 rpms...which should extrapolate to almost crank 400hp at 5500. An obvious decline from my previous run, but at higher RPM on an engine with one rod bearing pretty much gone...probably not too bad.
I at least got that one run out of it so I have an idea of where I need the fuel pressure to be before I swap another engine in and blow that one up too. I have a parts regal a year older with complete driveline that did run and drive at one point, just missing various parts and pieces. I will probably just do a full cradle swap...I think that can be done in a day. I'm off Wednesday, so if nothing else comes up, that's the plan.
I turned up the fuel pressure hammered it hard on the way home. It is rattling very loud now. But the good news is, with 75psi base fuel pressure on an otherwise stock tune, I saw 0 KR, so I do think being lean was the issue. That was at 11 degrees timing at WOT. It made 34.7 lb/min on the MAF at 4800 rpms...which should extrapolate to almost crank 400hp at 5500. An obvious decline from my previous run, but at higher RPM on an engine with one rod bearing pretty much gone...probably not too bad.
I at least got that one run out of it so I have an idea of where I need the fuel pressure to be before I swap another engine in and blow that one up too. I have a parts regal a year older with complete driveline that did run and drive at one point, just missing various parts and pieces. I will probably just do a full cradle swap...I think that can be done in a day. I'm off Wednesday, so if nothing else comes up, that's the plan.
I do appreciate the distinction and that you chimed in to make me aware of it in case I had not been, however for my purposes I ignore that and just always tune to and speak in gasoline AFRs.
Lambda is lambda, afr is afr. Widebands automatically correct for any fuel based on a gasoline scale anyway because they measure lambda and display AFR based on a calculation of AFR based on fuel type...they don't really care what the fuel is, that is just used to change the display to match actual air/fuel ratio. I don't care about that. I leave mine set on gasoline AFR, and discuss my tunes as such because that is what I started tuning on, that's what I'm used to, and it keeps me from having to do complicated conversions in my head.
Your wideband reading doesn't change with fuel type, unless you change the display setting. If you are tuning to the same lambda numbers and you switch fuel types without changing the gauge settings, you should still be tuning to the same indicated AFR, unless the fuel type just happens to like a richer or leaner mixture.
Methanol, for example, is going to require 2.3x or so the flow rate of gasoline. However, if you take a stock car, tune to 12.5:1 afr, then put in injectors that flow 2.3x more and switch to methanol, your wideband is still going to be reading 12.5:1 afr...unless you switch the gauge settings to methanol, in which case it will read whatever that lambda equivalent is in methanol (maybe 5:1 or something, don't know off the top of my head). Obviously that assumes perfect-world math and it will probably drift a little bit, but it will be a very close starting point.
It's unimportant on this car though because I was too lazy to hook up the wideband, so I have been approximating based on stock O2 voltage...which is highly unreliable, obviously, but I assumed the factory tune would be pig rich and I didn't have to worry about starting off too lean. Clearly that is not the case.
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