(Just a thought. But I have heard, but not seen the Power Curve Chart. That the Y385 engine has the most torque around the 2000 rpm range. If that is true, could you put a higher gear somewhere, maybe in the rear end, so that you could have a much faster top end speed, and overall better fuel mileage.
You are allready getting very good mileage, but an added gearing somewhere, might just help even more!!! And may help the durability of the engine, plus get you more of the top end speed that is needed nowadays on the turnpike's.)
I have thought the same thing, however there are reasons that I think that I'm right on the edge of my horsepower. For instance there is a one mile long hill on the way home from work that slows me down to 40 MPH even if I get a running start. I have tried that hill in 5th gear and 4th and even 3rd (my max govenor speed in 3rd is 37 MPH) and it makes little to no change in speed. (I can't climb it in 5th, the engine 'falls off' and starts to die)
Also when going down I-5 there are times I have my foot in it and I can only go 53-56 MPH (Head wind ect) no matter if I'm in 5th or 4th (My maximum govenor speed in 4th is 57 MPH)
These things seem to tell me that I am reaching my maximum HP for the engine, and that even with 'taller gears' it would make little change to overall speed.
You make a good point with mileage. I have noticed that I can exceed 50 MPG if I keep the revs down below 2000 RPM. (That is about 56 MPH in 5th gear) If I run it at 2650 RPM (about 67 MPH in 5th gear) I get about 38 MPG. If I had a taller gear it would increase my mileage at 65-67 MPH, but I don't think I have enough HP at 2000 PRM. It's just a little dangerous going out on I-5 at 55 MPH so I tend to run it hard and go as fast as I can. I seldom 'limit out' on RPM's
BTW, when I have said that I run the engine 'flat out' it means that I have the govenor wide open but not that the engine is at it's maximum govenor speed.
Any thoughts?
I have thought about putting a High Power 12V commercial cage fan onto the intake tube as a 'turbo-charger' when needed. Graingers sells it for about $150.00 Do you think it would add anything?
Thanks,
-Dan-