392 IC rebuild Thoughts.

[cworkman2]

I am currently mulling over rebuilding the 392 ic motor I have in my 1970 superior bus. The previous owner said they did a rebuild, but I have my doubts.
I was lucky enough to get two additional motors with the bus, giving me a grand total of three. They are all ic motors but I know the two on the stands have a spun crank bearing and the other has a bad rod bearing.
The current engine is mated to a allison mt40 , which I know is a timebomb waiting to blow. It works excellent now, but the parts are hard to come by and I plan on doing some travelling in this beast in the next few years.
So here is my question to the gurus out there. I'm looking for a reliable and robust motor. The 392 now pushes the bus along pretty well, but I keep a close eye on the rpms as we go down the road. I would like to be able to keep the bus moving 60-65 mph without making too much trouble for the motor. I am also considering swapping out the allison for a newer model (open to suggenstions here too)
I'm thinking my budget is gonna be 2000-2500 for the rebuild, could be more if I decide to have someone else do it. I'm a pretty competent mechanic and have build motors before, but this International seem to have a pretty narrow learning curve.
So hit me! I'm open to all suggestions and critiques.
Just a few pics to show you what I'm working on:
392 International Harvester photo by workman1975 | photobucket
20131021_175535_zps7da3419d.jpg photo by workman1975 | photobucket
20131021_175206_zpsf02427cd.jpg photo by workman1975 | photobucket

 

[FDChappie]

Welcome to the board, cool looking bus conversion. I'm in the process of rebuilding a 345 and the machinist is taking for ever to do the job. From what I've heard the 392 will go to higher rpm's with some big block Chevy springs. Perhaps a slightly warmer cam to work at those speeds.

 

[cworkman2]

What I've been eyeballing is a new aluminum intake, a warmer cam, the Chevy 454 springs to keep the seal on the valves. Mind you this isnt going to be a trail rig or torque monster. What I need is reliability and longevity. I'm trying to "lighten the load" on the bus by getting rid of some of the dead weight. No more water heater ( have an on demand unit) and other upgrades. The idea is to offset some of the current weight with a more efficiently thought out interior and building products.
Like I said, 60-65 highway is max for me...but the 150 gallon fuel tank will keep me going for a considerable time ( well at 9 miles per gallon...probably not that far)
anyone have any suggestions on a builder...know of anyone in michigan that they can trust? It seems everyone locally is mystified by the thought of tearing into the motor.
I am not against doing it myself, but I want to be methodical and have the best information at hand to do it.

 

[ihpartsjeff]

what I've been eyeballing is a new aluminum intake, a warmer cam, the Chevy 454 springs to keep the seal on the valves. Mind you this isnt going to be a trail rig or torque monster. What I need is reliability and longevity. I'm trying to "lighten the load" on the bus by getting rid of some of the dead weight. No more water heater ( have an on demand unit) and other upgrades. The idea is to offset some of the current weight with a more efficiently thought out interior and building products.
Like I said, 60-65 highway is max for me...but the 150 gallon fuel tank will keep me going for a considerable time ( well at 9 miles per gallon...probably not that far)
anyone have any suggestions on a builder...know of anyone in michigan that they can trust? It seems everyone locally is mystified by the thought of tearing into the motor.
I am not against doing it myself, but I want to be methodical and have the best information at hand to do it.

Have you seen our crate engines on the online store? They can be warmed up as well with some port matching, cam, etc and come with a nation wide warranty.

rebuilt engines - IH Parts America

 

[gulfdawg]

I built my 392, shoot 8 years ago. I spent 2300 in machine work and parts, isky cam and balanced, but I had to assemble it. I think you would be money ahead with one of their crate engines. It is so expensive to have an engine built these days. If I had to replace my engine I would seriously be considering their crate engine. Or a 5.9 cummins. But that is a whole different animal. Good luck.