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I currently have an 80 Scout with a 304 in it. I recently acquired a 392 from a 74 Scout and was wondering if this would be a straight swap or what I would need. Thanks!
304 to 392
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Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
A 392 inna '74 Scout II?? It had to have been previously swapped in, the 392 was never an option engine in the Scout II platform. At times, various dealers did install a 392 at the dealership before the vehicle was delivered to the end user/purchaser.
I bring this up because many folks have been fooled into believing they have a 392 when in actuality it ends up being a 345 pr 304.
That said, the 304 has a shorter deck height by about 1/4". That means the exhaust head pipes will have to be finagled possibly to make the connection.
If both rigs are automatics, then the flex plate patterns are the same, but each flex plate was a match to it's respective engine coming off the assembly line, so try and not swap flex plates around. Same holds for flywheels if manual trans.
I bring this up because many folks have been fooled into believing they have a 392 when in actuality it ends up being a 345 pr 304.
That said, the 304 has a shorter deck height by about 1/4". That means the exhaust head pipes will have to be finagled possibly to make the connection.
If both rigs are automatics, then the flex plate patterns are the same, but each flex plate was a match to it's respective engine coming off the assembly line, so try and not swap flex plates around. Same holds for flywheels if manual trans.
inprogress
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I didn't read before I posted, sorry. The 392 is from an International pickup truck.
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
Ok!
If the donor has not ever been previously installed in a Scout II chassis, the motor mounts that were originally installed on it are completely different when compared to a Scout II mount system. Depending upon year model, model series, and 2x4 or 4x4, the mounts are different also amongst pickups and travelalls!
A Scout II uses what we call "side mounts" (they also wrap around the front of the block, as such, the block needs to have the machined bosses and tapped holes for installing Scout II side mounts.
If the donor motor was in a '74 or '75 pickup, it also has "side mounts", but they are totally different in design and mounting points as compared to a side-mount Scout II engine application! Confused yet?
The earlier pickups with a 392 used either a "horseshoe" front engine mount or the "dog bone" style engine mounts, again, that depends upon which pickup chassis the engine was mounted in. Most of those engine castings will have the bosses on the block for the side mounts, but the bolt holes May not be drilled and tapped for installation. That can be done however with careful work while the engine is on a stand.
Next up is...the transmission you will use vs. The donor engine. That determines which flywheel or flex plate might be on the donor and what is on your current setup. So...we need much more information and details in order to help you with this. It is doable but there are many nuances that need to be noted and certain critical points that have to be addressed. Otherwise trickledown will eat your lunch!
We have been through this same type scenario many times in the past and know what to advise, but we just must have details in order to give you correct advice!
Lay out your entire plan, with the past setup on the Scout II and the details regarding the donor motor, then we'll move ahead.
If the donor has not ever been previously installed in a Scout II chassis, the motor mounts that were originally installed on it are completely different when compared to a Scout II mount system. Depending upon year model, model series, and 2x4 or 4x4, the mounts are different also amongst pickups and travelalls!
A Scout II uses what we call "side mounts" (they also wrap around the front of the block, as such, the block needs to have the machined bosses and tapped holes for installing Scout II side mounts.
If the donor motor was in a '74 or '75 pickup, it also has "side mounts", but they are totally different in design and mounting points as compared to a side-mount Scout II engine application! Confused yet?
The earlier pickups with a 392 used either a "horseshoe" front engine mount or the "dog bone" style engine mounts, again, that depends upon which pickup chassis the engine was mounted in. Most of those engine castings will have the bosses on the block for the side mounts, but the bolt holes May not be drilled and tapped for installation. That can be done however with careful work while the engine is on a stand.
Next up is...the transmission you will use vs. The donor engine. That determines which flywheel or flex plate might be on the donor and what is on your current setup. So...we need much more information and details in order to help you with this. It is doable but there are many nuances that need to be noted and certain critical points that have to be addressed. Otherwise trickledown will eat your lunch!
We have been through this same type scenario many times in the past and know what to advise, but we just must have details in order to give you correct advice!
Lay out your entire plan, with the past setup on the Scout II and the details regarding the donor motor, then we'll move ahead.
inprogress
New member
Thanks a lot for the information. Thought a direct swap May be too good to be true. Here is some additional info: just found out the donor vehicle and engine is not '74, it's a '71. Half ton 1110, shortbed, ex air force vehicle. It is two wheel drive, with an automatic transmission. The 392 is original to the truck, and rebuilt in the early 90's, then parked since. The only modifications to the engine (other than the rebuild) are an aftermarket intake and a Holley 850 carb added during the rebuild by the po. It has never been modified for installation in a Scout.
The Scout is an 80 traveller with original 304 still in it (including all the pollution equipment still intact). 727 auto transmission, 4 wheel drive with Dana 300 transfer case, 4 row radiator core.
I also have a '73, 1010 with a 345 in it, it's the same as the 71 otherwise.
I was hoping it would be a fairly direct, painless swap, just changing out things like the oil pan ect, but see now that it May not be so.. Thanks again.
The Scout is an 80 traveller with original 304 still in it (including all the pollution equipment still intact). 727 auto transmission, 4 wheel drive with Dana 300 transfer case, 4 row radiator core.
I also have a '73, 1010 with a 345 in it, it's the same as the 71 otherwise.
I was hoping it would be a fairly direct, painless swap, just changing out things like the oil pan ect, but see now that it May not be so.. Thanks again.
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
This new information changes everything to a degree! I'll be back tomorrow with comments, it's certainly doable with much more work than I think you anticipated!
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
Just tossin' stuff out here that comes to mind!
First off, the only "aftermarket" intake manifold ever offered for any IH 392 is the aluminum unit produced by rpt:
http://www.forums.IHPartsAmerica.com/carb-tech/76-beer-can-maneefol-guapo.html
And no way in hell can any sv motor use an 850 Holley! Ya can't even mount one on the 4v intake as the thermostat housing/waterneck precludes that (unless ya mount it cross-ways which is very problematic since that intake manifold is a dual plane unit). I know of a very few 392 motors that have been set up with a fabricated "remote" thermostat housing to allow clearance for either a center-hung Holley 4v carb or in one case, a wieand blower.
If the donor truck is a '71 with auto trans, that will be a borg warner unit, the tf 727 was introduced into production in late 1972 as a m/y 73 offering in both Scout II and pickalls. So everything from the crank hub back must be removed and set aside. The bw system uses a very unique flex plate hub system and flex plate, along with torque converter, they also use an electric switch under the throttle pedal for "kickdown". None of that stuff can be used with torqueflite.
An 1110 is a "heavy-duty half ton" model that was marketed as an emissions avoidance unit to some degree. I also drive one of those. Unless it's been swapped out, that one will use dog bone front mounts, and the side mount bosses May or May not be drilled/tapped, ya won't know until ya look.
The '80 traveler (and sii) is the only IH unit that had the "downgraded" cooling system bypass/thermostat system. That was a major cost reduction IH did only on the Scout II in it's last year of production. The thermo-system on the earlier 392 is far superior in my opinion.
You will need to move everything on the 304 from the crank flange out over to the 392, and seal the flex plate bolts that hold the crank hub/spacer/flex plate to the crank flange when doing so or you will have a massive oil leak!
The sii 304 oil pump, oil pan, and dipstick will have to be installed on the 392. Remove the 392 dip stick and seal the dip stick tube. If ya do a spring-over suspension, then ya can use the truck oil pump/pan/dipstick as it will then clear the axle upon suspension compression.
If the 392 has the extra-capacity cooling system (big nut fan clutch), then the fan May collide witha four row radiator inna Scout II, be very careful when looking at that. The fix would be to eliminate the water pump/fan system on the 392 and use the stuff on the 304, the pumps are identical except for the type fan hub that May be installed.
That's a start, I'm sure you will find more trickledown once ya begin the process.
First off, the only "aftermarket" intake manifold ever offered for any IH 392 is the aluminum unit produced by rpt:
http://www.forums.IHPartsAmerica.com/carb-tech/76-beer-can-maneefol-guapo.html
And no way in hell can any sv motor use an 850 Holley! Ya can't even mount one on the 4v intake as the thermostat housing/waterneck precludes that (unless ya mount it cross-ways which is very problematic since that intake manifold is a dual plane unit). I know of a very few 392 motors that have been set up with a fabricated "remote" thermostat housing to allow clearance for either a center-hung Holley 4v carb or in one case, a wieand blower.
If the donor truck is a '71 with auto trans, that will be a borg warner unit, the tf 727 was introduced into production in late 1972 as a m/y 73 offering in both Scout II and pickalls. So everything from the crank hub back must be removed and set aside. The bw system uses a very unique flex plate hub system and flex plate, along with torque converter, they also use an electric switch under the throttle pedal for "kickdown". None of that stuff can be used with torqueflite.
An 1110 is a "heavy-duty half ton" model that was marketed as an emissions avoidance unit to some degree. I also drive one of those. Unless it's been swapped out, that one will use dog bone front mounts, and the side mount bosses May or May not be drilled/tapped, ya won't know until ya look.
The '80 traveler (and sii) is the only IH unit that had the "downgraded" cooling system bypass/thermostat system. That was a major cost reduction IH did only on the Scout II in it's last year of production. The thermo-system on the earlier 392 is far superior in my opinion.
You will need to move everything on the 304 from the crank flange out over to the 392, and seal the flex plate bolts that hold the crank hub/spacer/flex plate to the crank flange when doing so or you will have a massive oil leak!
The sii 304 oil pump, oil pan, and dipstick will have to be installed on the 392. Remove the 392 dip stick and seal the dip stick tube. If ya do a spring-over suspension, then ya can use the truck oil pump/pan/dipstick as it will then clear the axle upon suspension compression.
If the 392 has the extra-capacity cooling system (big nut fan clutch), then the fan May collide witha four row radiator inna Scout II, be very careful when looking at that. The fix would be to eliminate the water pump/fan system on the 392 and use the stuff on the 304, the pumps are identical except for the type fan hub that May be installed.
That's a start, I'm sure you will find more trickledown once ya begin the process.
inprogress
New member
Thanks, the swap sounds complicated, but like you said, do able. I'll have to weigh options. As far as the manifold goes, I didn't pay enough attention to it to say for sure what it is. I'll check when the snow goes down a bit. The former owner identified the cfm of the carb, so I can't say for sure. It is most definately a large double pumper Holley though. There was no reason to doubt his word as he didn't have any reason to embelish. Both pick-ups (71 & 73) were free (the Scout belonged to wife's Dad. He had it for over 20 years before giving it to me). He was tired of looking for the time and space to do anything with them. Hmm, thanks for the tip. I'll have to get the carb number and try to figure that out. The carb is a normal looking Holley, not a spread bore like I'm used to seeing on IH engines. Thanks a lot for the information. I appreciate it.