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Or central Indiana! Or Michigan, Ohio, or anyplace my recent travels have taken me.
I'd avoid the ProFlo... I've heard nothing but bad things about their computer and the programming ability of it. Probably cheaper and easier to put a holley BBC manifold on it and run factory P01 or P59 ECU. You should be able to get a throttle body, pedal, wiring harness, and computer for dirt cheap from a junkyard and then just buy the intake, fuel rail and injectors from any speed shop like Summit or Jegs. The P01 or P59 will run the 4L80 just fine and you'll have tons of support available with factory GM parts at that point.
It’s actually gone up a fair bit in the last month in about every region of the us. I’d hazard to say every region but apparently you find the only place it’s going down.
I'd love to see these curves for our engines, so far my engine knowledge seems to be proven not applicable to old American V8's. Usually low RPM and almost lugging the engine is what's best for MPG as both the friction and pumping losses are minimized, but not with small and big blocks. Answer probably lies in these curves...
So technically a very low stall converter, like in modern transmission.
That's future proofing
Gas prices vary and there are times and places where fighting for fuel economy makes no economical sense. Also some of us may want to burn less fuel just for the sake of consuming less resources.
You would need a dyno and pretty precise equipment to create one, but it is doable. I bet GM has the curves for all of their engines, especially the newer fuel injected ones. For fuel Injected engines I think you could get pretty close to accurate numbers using the logging function in HP tuners using the calculated torque and fuel flow numbers. I'm really contemplating getting an EGT gauge and tuning my BBC for lean cruise. If I could get it dialed in right, that could be an improvement of up to 20% on the highway. You need a computer that is properly set up for it and an EGT gauge to do it right without melting pistons though.I'd love to see these curves for our engines, so far my engine knowledge seems to be proven not applicable to old American V8's. Usually low RPM and almost lugging the engine is what's best for MPG as both the friction and pumping losses are minimized, but not with small and big blocks. Answer probably lies in these curves...
So technically a very low stall converter, like in modern transmission.
That's future proofing
I'm not worried about gas milage with the truck. I agree gears would help get it moving from a stop, but they cost you at highway speeds. The engine makes enough torque down low to where it doesn't lug the engine. Plans later on down the road call for 4:10's and a 4L60E, or 80E tranny. I only use 10-12 gallons of gas a week. My 04 2500 HD only averages 12 MPG. I'm thinking with the gear and tranny change milage might increase 2- 4 MPG. Using the 60E with the 3.06 first gear I wouldn't even need a gear change. Being a K series, the gear change is twice the cost. Trucks don't get good gas milage.
3.73/4.10 rear end gearing, what makes that livable and driveable is the modern overdrive automatic. My OBS Burb gets off the line great with 3.42 and the first gear of the 4L60E. Big truck has a 4L80E and 4.10s, it's pretty snappy once the grunt gets to the rear wheels, back in the previous block LoL.... Both have plenty of legs on the highway too.
If you haven't watched the UNITY Garage series of videos you should. He talks about the timing curves on his big block Ford truck. He discusses that he can run upwards of 50 degrees of timing with lean mixtures at cruise throttle positions. David Vinyard also talks about it. You are on point about doing this with your truck. My truck at light throttle is at 15-16 AFR. I would like to take a trip at highway speeds to check my milage. The 9.5 is in stop and go traffic. The real benefit of fuel injection is the timing control. Thats their opinion. I agree with them. The fuel metering is second. The older FI was batch fired not much better than a carb. JMHOP. With direct injection the fuel metering is more precise. It brings along carbon build up and no cooling affect like a Carb.
You have to run more timing on a lean mixture because the combustion happens slower in extreme lean conditions. You could actually be hurting the engine and not getting the real benefit of lean cruise in the 15-16AFR range. A lean mixture does have significantly higher EGT's than a stoich mixture. That's why you should really have an EGT sensor when initially dialing in a lean cruise, you could be getting a miss from preignition or other reasons. What will happen when tuning for lean cruise is that as you lean the mixture out, the EGT's will climb higher and higher until about 16:1, then they will peak and sharply fall off. When they fall off, you will also find that the fuel used for a given load drops off at the same time. Once you find that fuel amount, you can then go in and start advancing the timing until you start getting some knock, or the engine efficiency starts dropping off. With an 0411 computer and HP tuners, you can use their RTT operating system and get the timing curves for cruise dialed in for peak efficiency while actively driving it.
