Suburban engine too small?

[SKOOLBOY]

There is a junkyard near my house that has a couple wrecked suburban's with good engines and trans. Would one be too weak for my full size chevy bus? Could I get it and use a gear reduction? Would it get good gas mileage? Has anyone every done something like this?

SB

[Steve]

The three quarter ton suburbans came with 454 ci and later 8.1L engines. These would be plenty for your bus. If you look at the older buses like mine they have very little horsepower and get very good mpg.

[the_experience03]

Buses came with 350ci, 366ci, 427ci, and 454ci motors frequently. These were almost always the industrial version which was much stronger, but less powerful than the regular version. I think a 454 would move a bus along just fine, but don't expect mileage. The mileage was pretty bad in the lighter vehicles as it was. Of course there are about a million hop up parts out there for them. For instance...you could find a set of Vortec heads for that 454 off a newer big block to increase power AND mileage.

If I were you I'd be more worried about the tranny. A turbo 400 tranny just isn't enough for a fullsize bus. It would be more than adequate in a short bus. There is a turbo 475 tranny that was used in heavier rigs that is about as stout as you're going to get without getting into an Allison. It was essentially a TH-400, but it has better clutches and straight cut gears. Those things are NOISY! If the bus already has an Allison I'm sure the bellhousing for a 366 (pretty common) would work just fine for you.