8V92 swap into MC8

MC8Mike · November 02, 2014, 08:31:51 AM

Quote from: luvrbus on November 02, 2014, 05:56:35 AM
Some of the parts Joe mention does not apply to a MCI like the turbo mounts the radiator does

Yeah I kind of questioned the turbo parts, my arrangement looks just like other MCI buses with the 92 in them. My turbo compressor and exhaust turbine housings are right on top of the blower, you could not get them any lower. Thanks.

akroyaleagle · November 02, 2014, 09:30:15 AM

I don't know anything about MCIs and birthing babies.

I just thought it might help. No worries, if the parts don't apply to your swap then you are ahead of the game.

Are all turbos on MCIs on top of the engine?

MC8Mike · November 02, 2014, 10:29:21 AM

Quote from: akroyaleagle on November 02, 2014, 09:30:15 AM
I don't know anything about MCIs and birthing babies.

I just thought it might help. No worries, if the parts don't apply to your swap then you are ahead of the game.

Are all turbos on MCIs on top of the engine?

I appreciate all input and yes as far as I know all the MCIs mount the turbo on top of the engine, thanks.

MC8Mike · November 02, 2014, 10:40:21 AM

The flywheel housing is giving me some concern, akroyal listed this:

5104464 low mount engine bell housing from a Ford Truck with a 6v92 or 8v9

My housing is from a Ford but it has 5104261 part number cast on. All I've been able to learn from the parts book is both are SAE 1 housings. It looks the same as the housing that is on the 71, starter location and such, but it is still in the bus at this point.

lostagain · November 02, 2014, 11:14:43 AM

At least in my 5C, there is no room for a turbo on top of the engine. It is mounted on the driver's side. The 8 is, I think, the same as a 5C, only 5 feet longer with a tag axle. You better measure for clearance.

JC

luvrbus · November 02, 2014, 11:28:20 AM

Joe gave some good info for the front mounted turbo those numbers are hard to come by for mounts and manifolds even DD has trouble finding numbers for those manifolds and mounts. On the MCI 5 the turbo is mounted on the side of the engine the top mount turbo won't clear without a lot of work so it easier mount on the side.

I have seen 8's mounted on the side also

I know for a fact as that were I mounted mine to keep the heat away from the under the bed oops sorry JC didn't notice you posted already

They work on the top of the engine in a 8 the difference is the 8 the engine goes in straight not on a angle like the MCI 5

chessie4905 · November 02, 2014, 12:00:02 PM

Several years ago my father met a local guy that had an MC-8 or 9, conversion with an 8-71. It was sure nice, but owner was really disappointed in it's power. On the Seven Mountains near Lewistown, Pa. It would get down to 25mph on the steep upper part. This was his first bus and figured they would run like a car. My dad had him take it down to Leid Diesel in Newville, Pa. and they installed a 425 or 450hp 8v-92. It would do the same hill at 40mph then, and he was happy with the power then. His only complaint then was that the fuel mileage took a significant hit from 6.5 to 4.5 mpg the first time he checked it.

luvrbus · November 02, 2014, 01:28:03 PM

No that Ford truck bell housing is not going to work in your MCI you are are going to be changing some gear drives around the compressor on the truck engine is located in wrong position and tilt and ? is your alternator belt or gear driven on your 8 and I think the power steering pump drive is wrong also you will need a MCI bell housing for a 8v92

MC8Mike · November 02, 2014, 02:16:52 PM

Quote from: luvrbus on November 02, 2014, 01:28:03 PM
No that Ford truck bell housing is not going to work in your MCI you are are going to be changing some gear drives around the compressor on the truck engine is located in wrong position and tilt and ? is your alternator belt or gear driven on your 8 and I think the power steering pump drive is wrong also you will need a MCI bell housing for a 8v92

That is not good news about the flywheel housing. I have the Ford air compressor in my storage but I can't remember how it was located on the truck when it was together. I have a belt driven alternator, I ditched that gear drive alternator when I changed the bus over to 12v.

bevans6 · November 03, 2014, 04:18:41 AM

Can the 8V-71 bellhousing work on the 8V-92? The rear engine mounts to the cradle are part of the bellhousing. The air compressor on the MCI lays over at a 72 degree angle but the one from the 8V-71 should work, I would think. You need a power steering drive somewhere on the back, on an MCI it is under the compressor. My biggest challenge in my engine swap was installing the power steering drive. At the front of the engine make sure your thermostat housings will work with the MCI coolant pipes. If not either you need to change the housings or the plumbing.

Like I said earlier, one of the easiest ways to scope out the project is to stand the two engines side by side and just make careful note of all the differences. I seem to recall measuring an MC-8 once and the engine bay was about 6" - 8" taller than the MC-5C. The bus itself is about 10" taller according to the spec's

Brian

luvrbus · November 03, 2014, 04:39:34 AM

No the 71 bell housing will not work on the 8v92 the end crank journal is a larger diameter on the 8v92 the 71 and 6v92 are the same diameter fwiw

lostagain · November 03, 2014, 07:13:34 AM

Since Brian says the 8 engine bay is 6 to 8" taller than the 5, then there should be no problem fitting the turbo on top. That would be nice, with equal length exhaust pipes to it. With the turbo on the driver's side, the exhaust pipe from the passenger side comes around the front, between the governor and the belt. Mine is wrapped, to conserve heat to go to the turbo, and to have a little less heat in the engine compartment. A turbo on top with short pipes from both sides probably spools up faster.

Mike, keep us posted on your swap progress. I find it interesting.

JC

MC8Mike · November 04, 2014, 08:08:43 AM

Quote from: lostagain on November 03, 2014, 07:13:34 AM
Since Brian says the 8 engine bay is 6 to 8" taller than the 5, then there should be no problem fitting the turbo on top. That would be nice, with equal length exhaust pipes to it. With the turbo on the driver's side, the exhaust pipe from the passenger side comes around the front, between the governor and the belt. Mine is wrapped, to conserve heat to go to the turbo, and to have a little less heat in the engine compartment. A turbo on top with short pipes from both sides probably spools up faster.

Mike, keep us posted on your swap progress. I find it interesting.

JC

I'll do that, I got a few hours in on the engine removal yesterday, bumper removed, coolant drained, drive line disconnected and a few other small things. Hopefully I will have it out in a couple days as time allows.
That is a good idea wrapping the exhaust and plan to do that. I found a seller on ebay that sells a blanket for the turbo and enough wrap to cover the pipes to and from the turbo. Makes the turbo more efficient and keeps the heat down in the engine bay.

luvrbus · November 04, 2014, 09:12:49 AM

Just the blanket on the hot housing on a 8v92 really doesn't do much I used the complete set of ATP on mine www.atpwrap.com

MC8Mike · November 07, 2014, 12:42:42 PM

I've got the engine and trans out of the bus and scattered about the shop. I've been thinking now is the time I should do something about my old HT740. I don't know the history of the trans, I bought the bus at auction and got no service history with it, anyway it has always had a lazy 2-3 shift. I have been shopping around and have found a couple possibilities and wanted to see what the board members thought about these choices. There are several rebuilt military surplus units up on ebay, part #23014539 with a 498 converter. And then there is a low mile used unit that belongs to a board member part #6885649. I don't know the converter number but it was behind an 8v71t. Both choices would save me a few bucks over going to an Allison shop and getting a rebuild. I'm also looking for a good muffler choice to go along with the 92. Thanks for all your input, Mike.