Cummins B3.3T In a FJ55??? (1 Viewer)

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Jan 29, 2011
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Location
Mid-Georgia
I had really planned on keeping the original F during my build but it is not working out. Every piece I take off of the thing has something wrong with it and I can't justify putting that kind of money into an engine that most people consider worthless. Been seriously looking at diesel as the way to go. Don't like the Toyota engines due to parts issues. I do like the Cummins engines as parts will not be an issue. I know some people are doing the 4BT but I don't want the 4"+ lift. Considering the fact that I will not be doing any rock crawling or any other serious offroading the B3.3T is really looking good to me. Does anyone know of the B3.3T being successfully put in a FJ55 or am I thinking about uncharted territory??? Thanks guys!
 
I had really planned on keeping the original F during my build but it is not working out. Every piece I take off of the thing has something wrong with it and I can't justify putting that kind of money into an engine that most people consider worthless. Been seriously looking at diesel as the way to go. Don't like the Toyota engines due to parts issues. I do like the Cummins engines as parts will not be an issue. I know some people are doing the 4BT but I don't want the 4"+ lift. Considering the fact that I will not be doing any rock crawling or any other serious offroading the B3.3T is really looking good to me. Does anyone know of the B3.3T being successfully put in a FJ55 or am I thinking about uncharted territory??? Thanks guys!

well first of all you are gonna spend an arm and a leg for the cummins over an F or a 2F. the main thing you will gain with the cummins is milage, and thats a great reason to go diesel, but plan on owning the rig for the rest of your life to see the return on your investment. I wouldn't be so quick to dismiss the F series motors on this forum, they are tried and trued bomb proof motors. Its one torquey motor for a 150 hp gasser, and It will go forever. That being said these guys know their B3.3T's


Eco-OffRoad, LLC: Home
 
Don't take me wrong, I'm not trying to say the F is no good. It's a good engine that when built properly will last a very long time but it is not cheap to do it properly. The valves need replacing, the lifters are pitted beyond grinding, the camshaft will need replaced, and every bearing I have seen so far is ruined. Basically this engine needs to have everything replaced. The rough numbers I have been coming up with are not pretty. That's why I started considering the B3.3T. It is more expensive but I think it would carry a little better resell value if I every got in a tight spot and was forced to sell.

Eco-Offroad has got a ton of info on the forum. I found the thread about the build that Profitt's did for him and it helped me a lot. Didn't see anything that would give me any problems but it's always the little things that get you. That's why I was hoping somebody may have put one of these in a FJ55 and could offer advice. Being the first one to do something can get a little expensive. :cheers:

Thanks for your advice!
 
Thought about it. The conversion is way beyond my capabilities so I got a quote from Proffitts....in addition to the sticker shock and wait list (12 a 18 mo. before they could even start), I ended up deciding it would be somewhat under powered for a wagon. No sense in trading an anemic, aging F engine for a sluggish diesel. .02 worth....

I'll be interested in the outcome should you go down that path...keep us posted. All the best
 
Don't take me wrong, I'm not trying to say the F is no good. It's a good engine that when built properly will last a very long time but it is not cheap to do it properly. The valves need replacing, the lifters are pitted beyond grinding, the camshaft will need replaced, and every bearing I have seen so far is ruined. Basically this engine needs to have everything replaced. The rough numbers I have been coming up with are not pretty. That's why I started considering the B3.3T. It is more expensive but I think it would carry a little better resell value if I every got in a tight spot and was forced to sell.

Eco-Offroad has got a ton of info on the forum. I found the thread about the build that Profitt's did for him and it helped me a lot. Didn't see anything that would give me any problems but it's always the little things that get you. That's why I was hoping somebody may have put one of these in a FJ55 and could offer advice. Being the first one to do something can get a little expensive. :cheers:

Thanks for your advice!

If you wanna spend the money on a diesel and you don't want to lift the truck to clear the deep oil sump of the 4BT, look into that isuzu 4DBT. great motor. came in Isuzu delivery trucks. smoother running than a 4BT and I believe is doable with a SUA. Rhino has one in a 55 and from what I understand he loves it. I still say find a strong 2f donor and slap that puppy in. my pig had a SBC in it when I bought it. if it had the 2f I would have never messed with an engine swap.
 
Thought about it. The conversion is way beyond my capabilities so I got a quote from Proffitts....in addition to the sticker shock and wait list (12 a 18 mo. before they could even start), I ended up deciding it would be somewhat under powered for a wagon. No sense in trading an anemic, aging F engine for a sluggish diesel. .02 worth....

I'll be interested in the outcome should you go down that path...keep us posted. All the best

I owned a 3.4L cummins powered FJ55, the 6AT- turbo, indirect. Near stock HP and torque ratings for a 2F. Not a lot of power, but it was far from sluggish. It wouldn't rev up like a V8, but it certainly would move. I drove the truck at about 70mph, with 33s, 4.10s, and a .73% overdrive. With the roof rack on, the truck got anywhere from 17-20, but with the roofrack off it would bump 23mpg.

The conversion was done by Royal Rose, and at the time the 6AT wasn't hard to source and was fairly inexpensive (about $1000 iirc). The truck needed an overdrive, and fairly tight spacing while shifting. The biggest limiting factor was heat- while the truck could still pull up hills, it needed to slow to keep the EGTs down.

Fun truck to drive no doubt, but honestly I would not go with an indirect engine again, especially if the truck saw any other use other than trail truck. The cost of an engine in good running condition, work needed to fit the engine into the truck (including transmission/ gearing costs), and the cost of operating the vehicle (cost of fuel, filters, oil, spare parts, rebuild bits etc.) all must weighed against the intended use of the vehicle.

Thus, for those with the money, time, and the whereabouts to do so, build it! Otherwise there is nothing wrong with a fresh 2F or even a V8- all viable, strong engines.

Edit- on availability, with a 35 gallon tank with no fuel gauge, I drove the truck till the ODO said I had gone 400 miles, with usually 110-15 gallons still in the tank. Never had any issues finding fuel for as long as I owned it.
 
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If you push the 4bt back and cut the firewall for the exaust you can pull it off without the lift. The exaust will be a issue, for it drops off on the same side as the front drive shaft. If I had to do it all again I'd make it trick as hell. I did mine with Chevy dana 60's that I had narrowed to 60" wm to wm. If I did it again i'd use a Ford 60 with a drivers side drop to fix the exaust issue. i'd keep the np203 205 doubled just use the ford transfercase though. The 4bt can put out some real numbers with little tweaking and the part are out there on craigslist to save bucks. Check out my pics!
 
Thanks to everyone for posting their thoughts. I do appreciate it as different points of view are always good to consider. Thanks!

It's not that I have a bunch of money to blow on this but no matter which way I go, it's going to cost quite a bit. If I do the rebuild properly, I am going to easily have $3k in it plus I still need to get rid of the 3 speed tran and source something with an overdrive. I can get the NV4500 from AA along with all the needed adapters to fit the F but from what I'm reading, MPG is still going to be ugly. At $4 a gallon, MPG is a big consideration for me. I started to consider the B3.3T to get a boost in MPG although it will likely cost about $2k more than a rebuild would.

I've been doing a lot of reading on this and it seems the 4BT and the 6BT are preferred by the Toyota crowd while the B3.3T is getting a great deal more attention from the Jeep guys. The 4BT and 6BT don't seem to be getting any great returns on MPG but I am finding some pretty interesting things with regards to the B3.3T. Granted it's taking a lot of time and effort for the guys to get things tweeked but the potential is there for some pretty decent MPG.

If I do it, the worst part is going to be the decision to separate an engine and a cruiser that have been together for 39 years. That's the "purist" in me coming out. Thanks again for the opinions!!!:clap:
 
htownfire - Thanks for the suggestion on the 4BT about cutting the firewall to avoid the lift. I don't think I could do it though. I'm one of the few people who actually has a good body. No real rust to speak of. No cutting or patching of any sort. Sure it has a few dents but big deal. Not sure I could cut the firewall on such a solid vehicle. I appreciate the info though.
 
It's not that I have a bunch of money to blow on this but no matter which way I go, it's going to cost quite a bit. If I do the rebuild properly, I am going to easily have $3k in it plus I still need to get rid of the 3 speed tran and source something with an overdrive. I can get the NV4500 from AA along with all the needed adapters to fit the F but from what I'm reading, MPG is still going to be ugly. At $4 a gallon, MPG is a big consideration for me. I started to consider the B3.3T to get a boost in MPG although it will likely cost about $2k more than a rebuild would.

You might want to drive a 4bt (or 3.3T) to see what it's like. The 4bt is a solid engine, albeit loud.

You might be able to find a well running 2F near you that someone's taken out in a FJ60 for cheap. $3K for a rebuilt F doesn't seem like it's worth it when you could find a cheap 2F.

The money you're looking at buys a lot of gas. (Just sayin'.)
 

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