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Discussion Starter · #1 ·
hi everyone. i registered like a year or so ago but haven't been here much. been wheeling my truck alot and put off a lot of ideas. sorry for the long winded post...

my RC has the original 360 in it now but i already swapped a NV4500 and dana 300 into it. it was a 727/203 combo(fulltime). saw my mileage go from 8 to 13. running 33's with 3.55 gears now. originally was going to go with a newer efi magnum 360 or even a 5.7 hemi, i am a mopar parts guy so getting a good core is no problem. but i started looking at the 4bt again after meeting a guy that has one in a 75 bronco. he says he gets 28mpg on good days, 25 average. the bronco has a nv4500, 4.10's and 35's. he was thinking about swapping to 4.56's but wasn't sure what it would do, if it would be worth it. he claimed 190hp and 470lbs. didn't ask what kind of mods he had.
so are those mileage numbers realistic? that power level i know is possible but the mileage #'s seem to be all over the place from the stuff i've read here and elsewhere. the power he's getting would be more than enough for me, my truck is only 5300lbs loaded with me in it. i do plan to go to 35's and 4.10s later this year. the truck is 50/50 street/off road. use it mostly for off road/camping trips, have driven it as far as moab(600 miles each way for me), with a lot of trips to borrego, death valley and bishop areas. so the torque of a healthy small block is fine for me. is the mileage worth the cost of this swap in the long run. that's where i'm at now. i have access to a good 6bt but don't really want to do that. too heavy, my frame would need a lot of reinforcing. thanx guys for any input.
 

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High 20's are realistic milage for a lighter truck. Mid 20's are realistic for a 3/4 to 1 ton single wheel truck.

Is it worth it? Probably not. There isn't much of a point to put a diesel in your wheeling/camping rig to me. I wouldn't want to wheel a 4BT vehicle. The torque is far too much for delicate manuevering with a stick and the noise makes communicating with a spotter impossible unless you can use sign language.

If you wanted to daily drive your RC and use it for occasional offroad use it would be a better choice since the mileage gain is moreso worth the initial investment.

With the NV4500 already in there a 4BT swap under $2K isn't out of line though so it might be a good option for you.
 

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I put a 6 out of a 93 W250 into an 85 W150 about 8 years ago.. pretty much a bolt in other than having to change the wiper motor,, Cummins powered trucks use a smaller wiper motor than the older gasoline trucks.. I didnt compare it to a similar year gas truck so they may also have the smaller ones too.. I also used the radiator support and exhaust from the 93 so I could retain the intercooler and had to make a spacer for between the od unit and the transfercase.. everything else was from the W150and bolted right up..
 

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Discussion Starter · #4 ·
found a great deal on a 6bt...

right after i posted this i had a 6bt fall right into my lap. it's an industrial engine, so the turbo/intake is wierd but otherwise it's like any 90-93 engine. don't think it was intercooled, tag says it was rated at 177hp. not sure i want to have that much wieght on my nose though. two of the guys at ramchargercentral.com have done it and still wheel them. i think the 4bt is a better fit for a RC. maybe i can trade with someone. also have a deal working with a buddy to get a complete eng/trans out of a 2002. he'd get the engine, i'd get the trans, adapter and other pieces to put the 12 valve engine in my truck. or save them for a 4bt.

i hear you on the noise, that is one of my concerns. at least at idle i can hear a spotter with my 360. but torque isn't that big a deal, i don't plan to build a monster engine. 350hp/400lbs is about what a mild 360 magnum will do with the right parts. 400-500lbs for a 4bt seems to be easy. a 6bt is a little different. start modding them and the torque goes up real fast. so i wouldn't want to do too much there. not sure that's worth it but for the killer price i'm getting it for. while i don't drive the truck every day, i do take some long road trips. that mileage would be nice. a lot to think about.
High 20's are realistic milage for a lighter truck. Mid 20's are realistic for a 3/4 to 1 ton single wheel truck.

Is it worth it? Probably not. There isn't much of a point to put a diesel in your wheeling/camping rig to me. I wouldn't want to wheel a 4BT vehicle. The torque is far too much for delicate manuevering with a stick and the noise makes communicating with a spotter impossible unless you can use sign language.

If you wanted to daily drive your RC and use it for occasional offroad use it would be a better choice since the mileage gain is moreso worth the initial investment.

With the NV4500 already in there a 4BT swap under $2K isn't out of line though so it might be a good option for you.
 

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The torque I'm referring to is at or just off idle. Gas engines don't have it. I have a pretty soft organic LUK clutch in my 4BT 71 and it's far too easy with no throttle to spin the rear tires in dirt/gravel without even realizing the clutch is starting to grab. That's with 4.10's and 35's. I don't wheel my truck, it's a DD, but have taken it on many camping trips through unmaintained mountain roads. Rough roads are the worst. It's impossible to use the gas pedal to smoothly maintain speed. Every bump moves the throttle and the truck lurches forward. I plan to add a hand throttle for the same situations this summer.

The lack of torque with a gas engine is nice for easier control at low speed with stick for me atleast. I don't think you couldn't do anything with a 4BT that a gas engine can, but think it would be harder to be "delicate" about it.
 

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Discussion Starter · #6 · (Edited)
ok, i see what you mean. yea, if i do this it will mean relearning the trucks new habbits. it will be a while before i'm ready to do this so i have time to look at this site and RCC to watch what what you guys experience. i have a brand new 360 magnum that is going in some time this summer. depending on how that goes i'll decide after our annual sept trip to moab if i'm going to go this direction. then i will still need to get stuff together to complete it. thanks for the input, very much appreciated.

dave.

oh yea, i'm using a LUK clutch now with my 360/nv4500. very happy with it. you used a dodge set up with a nv4500 right?
 

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I was under the impression that the Dodge first gen motor mounts would bolt right up to the 4bt and I could drop a 4bt right into my 93 Dodge pickup. Well, it will and it wont.

The monts do bolt up, but the starter lands right over the bolt bosses using a Dodge trans adapter. I also have the dodge powersteering and vacum pump assembly. It looks like it would be tight but if the starter didn't have a clearence issue I think the mounts would just squeak by the ps/vac set.

Anyway, just something to consider when planning your swap. I don't know if the older Ram Charger mounts and crossmember are the same as the 93 full sized pickup but I think they are.

I wish I had another way to mount a starter to this set so I could re-use the factory motor mounts.
 
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