John I don't know about all that stuff I know if it works or if it doesn't and I try really hard not to change stuff that is working and and just keep it the same. The best I do is to have someone replace what isn't working or fix it so it does what it is supposed to do.
I replace an 8V71 that was dying with this L10 so instead of worse than 265 hp I got somewhere around 275 hp not much of a bump up BUT it quit over heating leaking oil and I added an automatic trans. For me it was a good improvement and now my girlfriend drives it some too SO EVERYONE is happy. Gary did a good job on my install and I can understand how someone would not be happy with LESS power instead of more even if it quit overheating.
I am with you on all this. How rarely we get "everyone happy" at the same time.
I lust to learn how it works. Took my first clock apart while a 4 Th grader and from that i graduated to a small slot machine. Had never held a screwdriver to that point in life. Took me a week to get both running again. The clock came out of a trash heap and was rusty inside. The slot from my Aunts attic and had quit 20 years prior. Given you use of the technical term "that stuff" you don't have much of a passion for matters mechanical. That's OK as probably 90 percent of the population shares your level of enthusiasm and most are loved by someone and almost all do a good job at life. If I owned a bus, probably the only thing that would limit my tinkering would be my wallet and having something less than cat-like agility any more. We are different and accept that each, I hope.
Please don't hear me suggesting you modify your bus in any way. Not happening. My words were only for those that cared and found interest in those subjects.
Great the L10 worked out for you. There is one running around in a 4106 in a "T" configuration and i heard it gets 15 MPG. He is exactly like you. He got fed up with the overheating tired 8V71 and converted to a L10, just like you. He kept the 4 speed if memory serves. But he stayed with stock as far as he could....just like you.
And, like you, he is overjoyed with the fruit of his labor and is tired to death of people telling him he can't put a "T" config in a 4106 cause the frame will break and he should be due to it running around for 5 years or so. He drives it all over cause it gets such great MPG and has power to make good time. I am certain he hasn't changed a single thing he didn't need to change.
What MPG are you getting from your setup. The auto should cost you some efficiency but people here have dropped 10K just to get rid of their clutch. I lust for the Auto Shift stick that Brian(?) has. Those cute little box vans made by Izusu now come with a 6 speed stick and an auto shifting operation.