Cummins 4bt into my FJ60 (2 Viewers)

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I like your spring relocation, better than SOA in my view. Assume you did high steer as well?

I know everyone likes to hate on GM/Detroit, but the NA 6.2 is a decent engine, it fits like an SBC, it weighs about the same as a 2f, it uses SBC adaptors, and it will deliver similar mpg to a 4bt or Isuzu, and it's probably cheaper than a 4bt or Isuzu now.
 
The idea of a 6bt is both enticing and prohibitive at the same time. I would love the power and get up and go. I drove my buddys Dodge pickup a few times with one in it and LOVED it. Here's the thing: I got a factory remanufactured motor with 500 hours on it for $1950 (the 4bt, I mean). I'm not going to beat that deal unless I win the lottery, which could happen, I'm playing the Idaho lottery tomorrow. Anyway, there is also the space issue. The 6bt is longer and I really don't want to refab all the crossmembers and move the whole assembly back - which would also mean having the drive shafts altered, both of which are high dollar double cardons. I really don't need more than the 4bt provides. Plus someone pointed out above that to get the good fuel mileage, you have to be geared low. I have the Ranger torque splitter overdrive, the H55 five speed transmission and 4.56:1 ring and pinions. That combo with the 4bt will definately get me good MPG. Let me see how the 4bt goes before y'all start putting new ideas in my head, lol. 'Cause you know I'm thinking about it now, darn it! How many jobs will I have to work this summer to afford that? Hmmm...
 
I hope that factory reman motor was from a vehicle. What fuel pump does it have on it?

Since you got a nice deal on that motor I would stick with it. I was gonna do a 4BT swap until I found the deal of my life on a 1st gen Cummins. $1300 for a running and driveable truck delivered to the shop I had my cruiser at. Needless to say I decided to put the big 6 in there.

Another thing you should remember to check later is the shackle angle you have in the front there. Its pretty steep and will probably give a harsh ride.
 
Definitely check your gear ratios. You guys with 60's are lucky that you can get 3.70 gears. On the 80, I'm stuck with 4.11's due to the high pinion front diff.
 
The 4bt came from a yard tractor at Alcoa. They shut down the plant, I got the 4bt. What is the difference between one that was in a vehicle and one that was not? I don't know what pump it has yet, it is still intransit from GA. The shackle angle got nicer when I put the body back on (The body, by the way, is a total POS. I will address it later). As to the gear calculator, I like this one:

http://www.f-body.org/gears/

give it a try, I think you'll like it. What is the sweet spot for the 4bt, RPM-wise? I think, if anything, I have to go to 4.11:1.

Looked at some of your project pictures Stevo. Nice work, very nice work. Some pretty welding in there. How does she drive? Couldn't get to your 6bt swap for some reason.
 
Wyoming said:
What is the difference between one that was in a vehicle and one that was not?
What is the sweet spot for the 4bt, RPM-wise? I think, if anything, I have to go to 4.11:1.

Looked at some of your project pictures Stevo. Nice work, very nice work. Some pretty welding in there. How does she drive? Couldn't get to your 6bt swap for some reason.
Click to expand...

If it wasn't originally for a vehicle it probably has the wrong type of fuel pump. I know the ones for generators have pumps that run at certain RPM.

I always heard the sweet spot for cruising with these motors is around 1700 RPM. They start defueling at 2600 RPM stock. The governor spring upgrade is the best upgrade you can buy for 20$.

Hey thanks for the compliments, It rode great while my motor was running, tons of control off road without sacrificing stability.

Link Fixed.
 
davegonz said:
I've owned two 4BT powered wagons (62 and now an 80). I can tell you that you will never get 30 MPG. The best you'll get on the highway is low 20's (20-22 MPG) and you'll probably average 16-18 around town depending on how you drive.
Click to expand...

I agree with you about the 30 MPG, but I do average (combined city and highway) 24 MPG with my 4BT FJ62. I have checked it several times with GPS and it has been pretty consistent. I love my swap, but it is noisy. You can't have too much sound damping with this engine.
 
StevoJonesFJ60 said:
If it wasn't originally for a vehicle it probably has the wrong type of fuel pump. I know the ones for generators have pumps that run at certain RPM.

I always heard the sweet spot for cruising with these motors is around 1700 RPM. They start defueling at 2600 RPM stock. The governor spring upgrade is the best upgrade you can buy for 20$.

Hey thanks for the compliments, It rode great while my motor was running, tons of control off road without sacrificing stability.

Link Fixed.
Click to expand...

Torque peak for the automotive 4BT'S is ~1700 RPM for most CPL'S. Mine is really sweet at that speed. 3.70 gears would be better than the 4.11 gears in my 62, but my rubber overdrive helps somewhat. Look for engines with the Bosch VE rotary pump or the Bosch P3000 inline pump. These are usually for automotive applications and should work well on the road. If you get one of those and it turns out not to be automotive, I can get the pump numbers for the automotive pumps for you and a fuel injection shop can build and calibrate the pump accordingly. The 3200 rpm governor spring is a must do IMO, especially if you're using an auto trans. I can get the part # for that also and it is a mod you can do yourself. I work in a diesel fuel injection shop so I had some big advantages when I did my swap.
 
Good Stuff

1700 RPM? How can you not get great MPG at 1700 RPM? With 4.56:1 ring and pinions I should crush the diesel mileage. 1800 rpms in fifth gear and overdrive, I'll be at +- 67 miles per hour. I don't need to go faster than that...but I can.

Cullman, thanks for the offer of the information. I will probably take you up on it. I haven't seen the pump yet because I haven't received the motor. Shipping problems out of Georgia, but it should have gotten under way yesterday.
 
any issues with re-titling it to a diesel? not sure what laws are as far a swapping to diesel?

anyone know?
 
I have 35s on it now. I plan on sticking with them. I have 8 years on the tires and they are only half worn.
 
alaska60 said:
any issues with re-titling it to a diesel? not sure what laws are as far a swapping to diesel?

anyone know?
Click to expand...

No designation for it on a Wyoming title. Matter of fact he can do anything he wants to the truck here and the state could care less.

Wyoming, I have seen your truck around town, it is red and has tons of lift. So much lift the 35s look small! Mine is silver, black rims and on 35" Creepies.

Nice looking shop you got! ;)

It is a big difference going from raw v8 power to diesel power. You sure you want to dump the v8? What are your planned uses of the truck? Is gas mileage really that big of a deal to you?

BTW, if you need some parts I got lot's, not so much for your conversion but for other things. I am just on the other side of town.

:cheers:
 
LOL! RMP&O, I wish it was my shop! It's my boss' shop and he is VERY GENEROUS about letting me use it. I know your truck (I call 'em trucks too) it's one of the few that's memorable around town. I like it too. Funny about the lift - When I originally put the OME suspension on, I was a genious, it was the perfect height. Then, I loaded it down to move out here and it never cam back up again. I put longer shackles on, made sure the rear springs were on the proper side and was very frustrated. When I refurbished the frame and extended the spring hangers it was with this in mind. Then I put it all together again and loaded it down, it poped right back up again. It's a little more lift than I want, but I'm learning to live with it. Would love to see what you've got. Always looking for another FJ60 junkie.
 
Six trucks in my yard, wait nine if I count the work trucks. Only three are Cruisers though! I am lucky because where I live in the valley they don't give me a hard time about all these trucks sitting around.

I am working on a new project right now, a Mongrel of a Cruiser/truck. Got a whole bunch of crap I am selling off or trying to sell. I got some 40" Creepies for sale that will fit under your truck! ;)

You are welcome to stop by anytime and have a beer.
 
Can you guys tell me what the fuel pressure on a 4bt should be? Is it a mechanical pump? Does the motor need a computer of any type, simple or otherwise?

I may have a lead on an adapter to hook it up to my Chevy bellhousing and a flywheel. Keep your fingers crossed.
 
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