6bt fj40 pic requests???? (2 Viewers)

[dohcdelsol93]

just out of pure curiosity...i totally don't have a cummins 6bt 1st gen lined up or anything like that

but...on here and pirate there was a guy who shoe horned a 6bt into a 40 but all the pic links are dead.

After doing some measuring 6bt is only about 3 inches longer than a SBC from water pump pulley to bell housing, it is much deeper than a SBC but it's easy to modify the oil pan or get a marine oil pan.

I'm sure someone will chime in on weight (175 approx lbs heavier than a fully dressed 2f) take off the PS pump, Vac pump and AC compressor of the 6bt and now we are talking a very miniscule difference in weight (weight of bumper, winch, watch carb intake)...a light weight 4 speed aluminum transmission in place of the j30/h42 would also shave some pounds. Move the batteries(s) to the back of the rig for more savings. Who needs AC or ps or even a vacuum in an old 40 with manual steering and manual brakes anyway????

Then comes the issue of power...haven't people put BBC in these rigs on 3 speeds and 4 speeds with solid cases since the 70's with some 300-390 ft lbs of torque? on stock birfs none the less??? Isn't the rule of thumb: take it easy on the skinny pedal and she'll take care of you...maybe invest in some comfortable hiking boots just in case?

I'm more concerned with pics of what the engine looks like with one stuffed in there.

I'm assuming that if you had manual steering that steering box fitment issues would be none and it "should" fit front to rear pretty close to that of a 2f.

so...if you have pics or links to a pics...i'm interested in seeing them...from a curiosity stand point...not because I've looked at a 6bt and said...hey that should fit.

I would think OME heavy would mean heavy right?

 

[Fast Eddy]

Maybe there's a reason it's hard to find pictures. Too heavy for a '40, IMO.

 

[dohcdelsol93]

eh..150-200 lbs difference...not enough difference in weight there to make a valid argument.

Torque numbers yes...weight difference...no....have you seen some of the bull bars on some of the 40's from OZ? Enough metal to supply goals to every NHL team and still have enough left over to haul a few pounds to the scrap yard. If the 40 can handle the big bumper/winch combo (250-300lbs conservative) with the 2F attached..all this forward of the front axle i'm assuming the 40 suspension can handle it.


Further more if a YJ frame can handle a 6bt 12v...i KNOW a 40 will.

so...bump for more pics.

for the heck of it...bored at work...an ARB bumper is about 90-100 lbs...add on 125 for winch with cable, hooks...so...the curb weight of a 6bt fj40 with no big bumper is going to be within 50-100 lbs of that of a 2f Fj40 with an ARB and warn winch. Not a huge difference in there until we get down to power output and MPG's.

 

[the gimpey one]

Still think you should go Mercedes diesel

 

[dohcdelsol93]

I have a bike I don't really ride and I know a guy wanting to rid himself of a 6bt for the bike.


And although I like the om617 Turbo it would be a down grade in power compared to the present 305 SBC.


The 4bd1t I had in the 60 was running top notch but was still slow. Id like a motor running in the 200hp range with 300+ft-lbs torque. No computer. Will cruise at 2000-2200 rpms and net 22-25mpg.


I know I could probably tweak a 4bt to those specs but to what costs in long term reliability?

 

[GLTHFJ60]

My goal with my 4BT is to be in the 200hp range, which should be between 400 and 500ft/lbs of torque. Although 200hp is double the rated output of a CPL858, there don't seem to be any significant reliability problems. At that power level you're not really doing any significant mods. Get a turbo that puts out 30psi of boost early on (think HX30w6) and tweak the injection pump, then you're there. If that isn't enough power for you, then design a set of compound turbos (think HX35 over HX30) and you're mid 200s with a super flat powerband. There are guys who run 40ish psi with head studs and put more than 10k miles a year on their truck without any issue. Worst case scenario, you're taking a 400k rebuild interval down to 200k rebuild interval with a Cummins. I don't think that the durability would be decreased anywhere near that much, but that puts it in perspective for you.

When you're building the 4BT, there are a couple of things to look out for and a couple key thinks you can make to ensure reliability. #1, recheck the torque on the lower end fasteners. #2, install KDP. #3, ensure that you are using good fuel filters. #4, if you want to get crazy, install a bypass oil filter.

I've put ~10k miles on my 4BT this year, cruise at about the same RPM you do and get 20-22 mpg.

Are you sure that a fully dressed 6BT only weighs ~175# more than the 2F? I thought my 4BT weighed the same, if not a hair more than a 2F. The 6BT is a huge machine. Besides, 200hp is stock output for a 6BT, but 200hp equals at least 400ft/lbs of torque.

A 6BT might be a bit much for a 40.

 

[dohcdelsol93]

the dry weight of the 6bt according to our cummins manual (my shop also has whats left of a machine shop in it) says 942, this is with no accessories. fully dressed about 1150 fully dressed. Again...not too much more than our 12mpg 2f

In my 40 i would have only the alternator as i don't have AC or a need for a vac pump or the power steering. I only need the adapter plate, starter, flywheel and alternator. The starter and flywheel are 90% of all additional weight.

The transmission i'm planning on using is a ford RTS 4 speed overdrive (advance adapters calls it a T&C top loader transmission) This is a 10.5 inch long transmission which will weigh less than the stock h42.

Just for kicks (and because i have spares) i'll be matching it to the toyota 3 speed case. I've yet to brake anything with the SBC and my days of a heavy foot are long behind me.

I still haven't decided if i'll take the trade on the 6bt or not, i'm on the fence. I'm hoping someone saved some pics on their computer from the only 6bt fj40 i've read about on mud/pirate and will maybe share them.

This swap pretty much is going to be based on how well the 6bt fits inside the engine bay.

Whatever swap i do i plan on keeping the transfer case exactly where it is presently. With the front drive shaft flipped to the rear and the rear flipped to the front.

The ford transmission will have a a slightly shorter input shaft (about an inch) than the land cruiser output shaft so it will have a shallower bellhousing. The adapter plate from the ford RTS transmission to the 3 speed case is 1 inch thick. So essentially the engine mounting surface to the bellhousing will be in the exact same spot that i currently have now.

At this point i have exactly 35 inches to stuff a motor into my engine bay, i could maybe slide my transmission/TC assembly back 1/2-3/4 inches to add a little more space. This will also retain using a completely stock drive line (flipped but stock)

I could also flip my electric fan to the front of the radiator to add another inch if needed.

As she sits now a 4bt or 4bd1t would fit perfect with plenty of room to add an intercooler for that nice warm feeling you get knowing you added a few HP just by putting in a sweet looking conversation piece.

A 4bt and 4bd1t would also work...and moderatly wheel with as much as one could wheel with stock gears, open diffs and 32" tires without risking diffs, birfs or the 3 speed case made of glass...so why would i even consider a 6bt...well...what is life without whimsy???

 

[GLTHFJ60]

Where are you getting your fully dressed weight for the 2F? I was under the impression that the 2F was only around 750# fully dressed. Just look at a 2F block next to a 6BT block. The 6BT is MASSIVE compared to a 2F.

Go for it man, I'l love to see a 6BT in a 40. If it came down to it, you could extend the nose of the 40 bodywork by a couple of inches and have plenty of room.

 

[overpaid slacker]

this thread makes me feel a little more at ease with my 4bt fj40 swap. I have concerns that stock diffs and toyota tranny will hold up to the torque of the 4bt. This project has been on hold for a while and I am looking forward to get going on it again.

Man, a 6bt in a 40 would be a beast! Those first gen 6bt's are incredibly noisy, but are known to be million mile motors.

 

[dohcdelsol93]

People have been running BBC for years...long before the internet and all these aftermarket companies came out giving us more affordable and readily available upgraded parts to make our already stout built cruisers or other 4x4 machine that are lesser made more indestructible.

With a 396 under the hood you could break birfs at will if you wanted.

Its all about your driving style and more importantly self control.


and if you can weld/know someone that can weld dont worry so much about the deep oil pan.

Those can be modified to make it much shallower to clear the front diff. IIRC the oil pan on the 4bt and 6bt can also be flipped so depending on your transmission you could flip the pan to the side with the most clearance. With a long transmission you want the engine mounted as forward as possible to help the drive line angle.

 

[GLTHFJ60]

Yeah, the weight of a dressed 2F is ~750#, so you're talking 3-400# additional weight.

https://forum.ih8mud.com/60-series-wagons/200757-2f-weight.html
https://forum.ih8mud.com/40-55-series-tech/234552-how-much-does-2f-weigh.html
https://forum.ih8mud.com/40-55-series-tech/14652-how-much-does-2f-motor-weigh.html

Torque curves are the difference between a BB and a cummins. A cummins hits peak torque at about 1800 rpm. Where does a BB hit its peak torque?

 

[dohcdelsol93]

Yeah, the weight of a dressed 2F is ~750#, so you're talking 3-400# additional weight.

https://forum.ih8mud.com/60-series-wagons/200757-2f-weight.html
https://forum.ih8mud.com/40-55-series-tech/234552-how-much-does-2f-weigh.html
https://forum.ih8mud.com/40-55-series-tech/14652-how-much-does-2f-motor-weigh.html

Torque curves are the difference between a BB and a cummins. A cummins hits peak torque at about 1800 rpm. Where does a BB hit its peak torque?

You will see weights of the 6bt estimates all over the place. A flywheel weighs 60lbs more than a flexplate. A P pump weighs 50 lbs more than a VE pump. Some have an alternator set up with a vac pump, others have a bolt on vac pump for air brake systems.

Plan on the 6bt being between 1000-1150lbs with all bolt ons, if you are setting it up for a cruiser.


If i were setting one up for my 40 i wouldn't need all those bolt ons so id save some 60 lbs since all i need is an alternator. .

even then, the weight is not a deal breaker unless your springs are shot or you are running a huge bumper and winch.


















A BBC even stock can put out 300ftlbs or torque out at 2000 rpms. @2000 rpms is about where many stock torque curves flatten out for the BBC.

With head work/bolt ons/cam you could get closer to 400 at 2000 rpms. Who puts a BBC into a cruiser without a cam and head work anyway????

 

[Fast Eddy]

Plus you can get a 427 with an aluminum block (and free shipping).

http://www.ebay.com/itm/Chevrolet-P...Parts_Accessories&hash=item48536e659d&vxp=mtr

 

[GLTHFJ60]

All I'm saying is that it's gonna be heavier than you expect. I want to see you do it!

 

[TCinVA]

My first posts on mud dealt with this, I had an old cummins truck and wanted to do this. I actually found an old thread from somewhere with a few pictures. After more research and consideration, I went SBC instead, and glad I did. I rode in a friends stretched 40 series with a 4bt, it had a ton of power and was unstoppable (a well built rig). I would urge you to do a 4bt if your heart is set on a cummins- you can get plenty of power out of one and the truck will be much better balanced.

 

[1974FJ]

i spent a great deal of time working with fj40s and cummins. Ive got a 4bt in mine with a th400 automatic trans and i had a nv4500hd 5speed manual before. believe me when i say a 4bt is plenty for a fj40. I dont have much in modifications to mine other than a different turbo and mine is plenty powerful.
The only reason to use a 6bt over a v8 is for cheaper torque. But honestly if you need a 6bt to tow somethings then your towing too much to be safe in a fj40. If you want to build it to be cool and wicked, then by all means turn the fuel up and burn the coal!!!!

 

[overpaid slacker]

Hey Martin, why the switch from the nv4500 to an auto? It would seem that the 4bt would be a lot more fun with the stick.

 

[Duiser Offroad]

A 6BT does not belong in a 40. Period. Way too heavy and big, maybe you can fit it, but who wants too.

A 4bt is a great alternative.

 

[kcustom73]

If you have the funds & time, I say do it. Won't be easy but it will be unique.

I just stuffed a GM 6.5 rear turbo diesel into my 40 that's been tune for about 200hp/400ft-lbs. The perk of this motor is that's it about the same size as a SBC and weight about the same as 2f.

 

[1974FJ]

Hey Martin, why the switch from the nv4500 to an auto? It would seem that the 4bt would be a lot more fun with the stick.

I originally built the truck with the 5speed as a daily driver but decided I wanted to wheel it more and I personally like wheeling with an auto. Plus unless your towing, autos are more fun on turbo diesels in my opinion, I've got a 6speed power stroke too.