Cummins 6BT

GLTHFJ60

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I wanted to know if anyone has done the 6BT conversion. I have posted on other threads about wanting to pop a 1HDT into my rig, but the lack of parts as well as the price of parts has got me reconsidering....

The way I see it, the Cummins has more power, it is relatively cheaper and the parts would be much less expensive, not to mention incomprehensively easier to find.

People have eluded to this conversion, but I know nothing about doing it.
-What transmission to get
-What TC to get
-Available space in the engine bay
-Breaking Axles or Driveshafts

Anyone with knowledge on this, please help.

Oh, by the way, I wanted to buy a five speed for my 2F that would work with the engine that I want to swap in. Is there a transmission in existance that is for a 6BT that will mount up to a 2F?

Thanks guys!

:beer:
 

PabloCruise

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Andre (dieselcruiserhead) stuffed a 4BT into his 55...

I think the 6BT is a tight fit.

There is a 6BT getting stuffed into a Pig over on Pirate...

I know the 4BT gives a lot more room and still pops out plenty o' torque!

Tranny choices? I think the Cummins have a "standard" Chevy bellhousing bolt pattern. So you could go NV4500 for your 5 speed.

I do not know what tranny/t-case Andre put in his Pig. I wanna say he went 4500. Not sure.

Good Luck!
 

VTCruiser

 
 
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two things i don't like about the 6BT it the school-bus like noise and its heft. the engine is capable of making TONS of power which like, but i think it is a little over the top for the cruiser chassis which I guess would be rated at about 1/2 ton (?).

the 4BT might be a better choice for the cummins route.
 

RredFJ40

 
 
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I'm starting to look for stuff for a 4BT swap. I'll be going with an NV4500. The trick though will be keeping the RPMs down to preserve the motor.

what the heck do you mean by this?

"Is there a transmission in existance that is for a 6BT that will mount up to a 2F?"

do you mean for the meantime?

If so you could adapt the NV4500 to the 2F via an AA adapter and then pull that stuff when you put the Cummins in.
 

PabloCruise

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VTCruiser said:
two things i don't like about the 6BT it the school-bus like noise and its heft. the engine is capable of making TONS of power which like, but i think it is a little over the top for the cruiser chassis which I guess would be rated at about 1/2 ton (?).

the 4BT might be a better choice for the cummins route.
I think the 4BT weighs about the same as a 2f...

My buddy started running biodiesel in a pre-Duramax Chevy diesel - said it quieted the injectors down quite a bit!

Anyone got specs on a 4BT. I wanna say they make ~300 hp. That should be enough!
 

Tapage

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I agree with other opinions that say, 6BT is maybe to much for your TLc aplications, with the apropiate gearing, you can use the max power of 4BT with less weight.
 
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if i had to do the swap,which i wolud admit sounds apealing i would go with the 4bt, the 6bt is pure overkill doesnt make much sense imop, besides the 4bt is more than enough power for the cruiser chassis and some would argue a little overkill as well? anyways goodluck with either diesle u choose! :flipoff2:
 

Mike S

 
 
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No one has mentioned the depth of the 4BT and 6BT. I believe that they will not fit into the stock engine bay. Too tall?

M
 

Spook50

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Mike S said:
No one has mentioned the depth of the 4BT and 6BT. I believe that they will not fit into the stock engine bay. Too tall?

M
I believe the 6BT is too tall, due to the oil pan being deep as hell, but I'm not sure about the 4BT. Greenpig put a 4BT in his 55 though, so he could probably answer alot of questions. I just wish I could put a diesel in my truck without having to deal with the downtime that'd be required to do it right :eek:

Maybe if I got that damn VW running...
 

polarweasel

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Incidentally, a Cummins mechanic told me that the oil pan (and pickup) is reversible on 4/6BT engines. That might be a useful thing to know when you're looking at clearance issues...
 

GLTHFJ60

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Does anyone know how much longer the 6BT is in comparison to the 2F?

Originally posted by RredFJ40

what the heck do you mean by this?

"Is there a transmission in existance that is for a 6BT that will mount up to a 2F?"

do you mean for the meantime?

If so you could adapt the NV4500 to the 2F via an AA adapter and then pull that stuff when you put the Cummins in.
That is exactly what I meant. I wanted a transmission that would work with my 2F that would also work with the 6BT. Was teh NV4500 the transmission that came stock on the 6BT? Could it handle the 6BT's torque over the long run?

:beer:
 

Mike S

 
 
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NV4500's have been adapted to the 2F. H55F's can be adapted to Cummins engines which fit with GM bellhousings. If I was putting a Cummins in my truck, I would use the NV4500 - a good strong 5 speed with a taller overdrive than the H55F. The Cummins would have plenty of torque to make the taller overdrive work very well in such a light truck.

I think you would be wise to consider a 4 cylinder 4BT or 4BTA.

BTW, I have been looking at marine engines, and one of the ones that impresses me the most is the Volvo Penta D4-260. This would be a killer type engine for the Landcruiser - small, lightweight, and gobs of power. Just dreamin'.

M
 
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6BT will fit in a 60 with OME (2.5") height or taller lift in a FJ60 though taller is better. Engine weighs over 1000-1100+ lbs though versus 2F which is about 800, about the same as 2F. My host is down right now but check my site when you get a chance. NV4500 will bolt to a Cummins or a 2F but would be wasted money I think, I would do it all at one time. 6BT will work but is torquey. I am interested to see how Perry Pillard's works (6BT in a FJ55, even tighter fit). I do have the 4BT and I love it, I would take this engine over the 6BT in a heartbeat for a cruiser unless it saw road time only I think.. You can also adjust the power on them easily...

From their gievn applications:
6BT's out of Dodge trucks have SAE #3 which is a round bolt pattern, not Chevy
4BT's mostly came in breadvans with Chevy 350 bolt patterns though there are some weird ones with ford patterns or even SAE #3. The back plates of all B series engines are interchangable, 6BT, 4BT whatever. So lots of people will sell their chevy plate and buy SAE #3 (Dodge) or vice versa.
 
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Also HP outputs:

4BT stock 105 hp, about 255 ft/lbs of torque
4BTA stock 120 hp, 302 ft/lbs


6BT, depends on the era. 1989-1993 Gen 1 Dodge trucks about 160 hp, 400, ft/lbs
Later models have more...

Remember it is really about the torque. The 4BTA puts out more torque than most V8's for example, and a lot of it right off the line. It will literally idle right through anything, including brakes usually, and will not stall...

The 4BT 105 hp model powers a 60 petty well. My 120 hp 4BTA will fly up big long mountainout grades at 80 no problem, mildly turned up, this is also with 35" tires.. It is also really easy to turn these up for more power. Out of the box they have great efficency but are a little lacking on power. ALso, all power (and efficency) mods from 6BT's work great on 4BTs.

I had to be SOA or maybe a 4" lift and I am fine to fit this engine. But yes it is deep. Oil pans are reverable but it does not matter much in this case as you still have to have the sump to the rear in a cruiser...
 

squeezer

 
 
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dieselcruiserhead said:
From their gievn applications:
6BT's out of Dodge trucks have SAE #3 which is a round bolt pattern, not Chevy
4BT's mostly came in breadvans with Chevy 350 bolt patterns though there are some weird ones with ford patterns or even SAE #3. The back plates of all B series engines are interchangable, 6BT, 4BT whatever. So lots of people will sell their chevy plate and buy SAE #3 (Dodge) or vice versa.

'dre What is your source of this info ? To the best of my knowledge the Dodge 6BT's use a specific plate depending on the application. (Different plates between the Getrag and the NV4500).
SAE #3's are out there but not common. More common in the medium duty applications is the SAE #2.

Known automotive adaptations:

Chevy: common in "bread vans" (tilted to alow the injection pump on the 4BT clear the firewall of the Grumman Olsen P30 chassis) same base adapter used with auto's and sticks but with different flex-plate/flywheel components.

Ford: small block Ford pattern, details as Chevy above.

Dodge: Getrag, NV4500

SAE #2: various wet, dry, aluminium, cast, mount ears, no mount ears, starter positions, cluth options... Literally dozens of applications.

SAE #3: As SAE # 2 only not as common. Pretty hard to find a clutch that will hold a 6BT. More direct drive, equipment type applications.


I worked for an OEM that spec'd B series in a line of equipment and just happen to have a complete set of Cummins Engineering application manuals, and OEM install drawings, pretty good source of info. That and I have bought not one but two Frito Lay trucks... Anybody want a drive it home 6BT powered Frito Lay tractor ?

Cheers

Chris
 

Tapage

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Mike S said:
BTW, I have been looking at marine engines, and one of the ones that impresses me the most is the Volvo Penta D4-260. This would be a killer type engine for the Landcruiser - small, lightweight, and gobs of power. Just dreamin'.

M
Penta with 1230 lbs .. !
 

Mike S

 
 
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Well, maybe not so lightweight - but that weight includes the transmission - but you're right - still heavy. But probably lighter than a 6BT. I like the idea of a 4 cylinder turbodiesel that puts out 260 horses from 3.7L. I'll bet it's quiet.

M
 
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