With far better fuel economy and reliability than any chev/detroit V8 diesel.
Diesel engine into FJ80...questions
- Thread starter avocadofarmer
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With far better fuel economy and reliability than any chev/detroit V8 diesel.
Fuel Economy between the 4bt and 6.2 will be similar. Guys with military chevys that have a 3speed auto(th400) are getting low 20mpg out of the 6.2. The lancruiser is alittle lighter and most of the time are going to have overdrive so better milage. There is a guy in the fj40 forum on here that put a 6.2 in his 40 and is getting mid 20's. Mid 20's is all you are going to get out of the 4bt and unless you turn up the pump on the 4bt you will have less horsepower then a 6.2 so slower. I have been reading on the 6.2 and its a detroit deisel which means it will run forever trust me I work in the marine industry and detroits are still everywhere and they were designed in the 30's or 40's. A well taken care of 6.2 will go 500k might be an oil burner by that time, but it will do it. And if you look around you can pick up a military take out 6.2 with under 60,000 miles for under a grand. They come with 24volt electrical systems if you are in to that kind of thing if not you have to change a few things such as starter and fuel selinoids. If you want power, milage, and reliablity 6bt if you want milage and reliability go 6.2 or 4bt if you are rich(more expesive then a 6bt not really that more milage).
Some quick lessons on fuel economy.
1. The fewer cylinders you have, the less fuel you will use.
2. Direct injection (aka 4BT cummins, 4BD1T Isuzu etc) use less fuel than indirect injection.
3. Smaller turbocharged engines use less fuel than bigger displacement non turbo charged engines.
Given the above three points, there's no way a 6.2 can approach a 4BT for fuel economy. The isuzu is slightly more efficient again than the cummins.
Rusty wasn't getting mid 20's.
The GM 6.2 and 6.5 diesels are no relation to the 2 stroke detroits that some people love to bits.
Why do you think the military take them out and sell them cheap?
The interweb is full of tales of woe for these engines. Take this one for example:
GM-Diesel.com - My 83 6.2L has cracks
Power of a non turbo 6.2 is 130-140hp.
The Isuzu and cummins 4's have that much power stock.
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Does anyone know anything about putting a Duramax in one?
I read on here that a guy was working on it, but no new news. I would like to put a NV4500 behind it to avoid the electronics and cost of the allison. If I am going to the hassle of all this work, I'd like to put the best and most reliable engine in there.....also, used Duramaxes can be found for 2.5k and up...cheaper than some 6.2/5 thats 20 years old...also know of a stand alone controller for the electronics of the engine.
Would it fit? I think it would.....
I read on here that a guy was working on it, but no new news. I would like to put a NV4500 behind it to avoid the electronics and cost of the allison. If I am going to the hassle of all this work, I'd like to put the best and most reliable engine in there.....also, used Duramaxes can be found for 2.5k and up...cheaper than some 6.2/5 thats 20 years old...also know of a stand alone controller for the electronics of the engine.
Would it fit? I think it would.....
Military is actually pulling these out of Hummers cause they don't have enough power once extra armor is added to protect against IED's. They really didn't have enough power before, but I have read numerous stories of guys getting low 20 miles per gallon in 3speed auto military cucv's which are heavier then cruisers and don't have overdrive so mid 20's in a cuiser is probally gonna be the norm and from all my reading on here so far no one has really posted too much about fuel mileage in a 4bt cruiser. I have read some stories of mid 20's and thats it, nobody is getting 30+mpg with the 4bt. So is the extra 2-5k for the swap really that worth it? Reliability? I have read about problems with the 6.5, but that is because International took over the casting of the block and tried to save a buck and now the webbing cracks. Some of the later 6.2 blocks might have the same problem, but I have not heard of that problem in the early 6.2's that were built by detroit diesel which is a company not a motor. The motor most people call detroits have many names and not all of them are 2 stroke. Yes the 6.2 is rated at the same hp level as the late intercooled 4bta's and yes a motor with 4 more cylinders can achieve similar fuel consumption ratings. I have read that the 6.2's were actually designed for economy and not for towing which is why that had to stick a turbo on it and up the displacement to use it in a truck made for towing and it still wasn't worth a s*** then. The 6.2's are a great resource for us guys that wan't to put deisel engines in vehicles that didn't originally come with them, they are cheap and use a chevy trans bolt pattern which means you can put them in anything, they will also run on about anything and achieve significant fuel mileage while doing it. I say put whatever engine in whatever vehicle, but for what I am building personally the 6.2 can't be beat I will be running the thing on alternative fuels and not giving at s*** cause I am not going to bomb a 2000+ dollar motor if I blow it up running too much used motor oil or atf or vegi oil or whatever I will find another one for 500 bucks and throw it in there.
sandcruiser
....back in the saddle again....
I've heard the 4bt cummins in an 80.... on the highway, no worries. at idle, it is loud.
just my 2 colones
just my 2 colones
Plenty of mileage records on 4btswaps.com, including people who've pulled 6.2's and 6.5s to replace them with cummins B motors.
Yes there are people breaking US 30mpg with a 4BT or 4BD1T. But they're in 2wd vehicles.
25 US is more common in a 4wd vehicle.
Those V8 diesels were built for better fuel economy than a petrol V8. That they acheived.
Here's a thread which includes former 6.2 and 6.5 owners, cummins owners and photos of the new completely reengineered replacement for the 6.2/6.5.
are 6.2s anygood - Cummins 4BT & Diesel Conversions Forums
If you think you'll find the 6.2 to be underpowered, you probably won't be happy with the 4BT or the Isuzu either.
I would recommend either the 6.2 or the Isuzu. I run both in 60's.
The 6.2 60 gets 18MPG hwy and the Isuzu 4BD2T 60 get 20 MPG hwy.
pumps turned up on both.
The power is about the same, maybe a slight edge to the Isuzu. The Isuzu will pull a mountain grade better than the 6.2 without running out of steam.
I guess the Isuzu somewhat gets the nod on power and economy.
I've daily driven the 6.2 60 for six years without any major problems. Only problems were injection pumps. I bought a beatup 82GMC truck for $75 with unknown mileage, pulled the 6.2 out , and been running the hell out of it in my Land Cruiser ever since. Now that's value.
I do admit that I like the Isuzu a little better though.
Avocadofarmer - this question keeps coming up (probably because it's a good one). I know of at least two conversions on the board. One is Codyc (I think that's how it's spelled) in Canada. The other one is cumminscruiser who's in ca. and is very happy with his conversion. You should be able to search them. For my .02 go with the 6bt. I agree with your thinking that if your going to all the hassle get something that's going to last for a million k and you can build lots of power if you want it.
The Duramax is the engine made by Isuzu, right? Would make an interesting swap for sure.
Well said
I believe the original Duramax was a joint engineering effort by GM/Isuzu but Isuzu is no longer in the picture.
Duramax lexus on youtube.
YouTube - LEXMAX LX470 Duramax BURNOUTS
YouTube - LEXMAX LX470 Duramax BURNOUTS
made by isuzu still but once it runs its model life you will see a different motor coming from gm as isuzu and gm has cut ties.
Maybe its from the guy that put this together.
https://forum.ih8mud.com/100-series-cruisers/115929-crazy-100-series-conversions-alan-podvin.html
A guy I met here in Oz had an 80Series with a 6.5 V8 turbo diesel in it. It ran beautifully, he was very chuffed with it. It sounded awesome too!
In Oz it's a very common conversion to put a 6.5 turbo in LandCruisers and Patrols.
I worked in a caravanpark were I used to drive an old '78 F100 with a 6.2 in it. Awesome! Lots of torque, that thing could pull a house down.. It was put in more than 10years earlier and was literally NOT serviced. It only got oil top-ups and I used to keep putting water in the radiator all the time.
It was only doing stop-start driving (that is, drive 30yards, stop, drive 30yards, stop... and so on) for the whole day every day.
It ran rough but it kept on going.
If I lived in the US and had an 80 I would not hesitate to stuff a 6.5 turbo in it. Especially if they're not that expensive from what I read here.
In Oz it's a very common conversion to put a 6.5 turbo in LandCruisers and Patrols.
I worked in a caravanpark were I used to drive an old '78 F100 with a 6.2 in it. Awesome! Lots of torque, that thing could pull a house down.. It was put in more than 10years earlier and was literally NOT serviced. It only got oil top-ups and I used to keep putting water in the radiator all the time.
It was only doing stop-start driving (that is, drive 30yards, stop, drive 30yards, stop... and so on) for the whole day every day.
It ran rough but it kept on going.
If I lived in the US and had an 80 I would not hesitate to stuff a 6.5 turbo in it. Especially if they're not that expensive from what I read here.
