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i have a line on an isuzu engine for a sweet deal but want to know more about them first. the one i'm looking at is from an 89 NPR and has a gm style sae adapter on it and an auto trans behind it. any pros or cons to this engine?!

thanks in advance!!!!
 

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go for the Isuzu... The NPR motors don't shake nearly as much. IMO they have almost as good of reputation as the cummins.

I'd love a 3.9 in my Land Cruiser.. I found one but passed cause of the unknown condition.
here is a great link http://www.isuzudieselswapper.com/




great site Andre:jester:
 

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Discussion Starter #5
thanks for the info guys. i can get the engine for a screaming deal so i might just jump on it.:smile:
 

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it is sacreligious of course but if it is good shape I may possibly be willing to trade for my good running 4BT if you are interested.. I have always wanted to do that Isuzu diesel swap :) But fair enough to you, maybe you should do it first also :) The 4BTs are pretty good actually with the correct motor mounts if you ask me, really pretty drivable/streetable :)
 

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excellent information in the 'mud thread..
http://forum.ih8mud.com/showthread.php?t=128585

I became fascinated with this engine as my first choice before I stumbled into a cheap 4BT and this all began a few years ago... I have pages and pages of info and also haven't installed it myself or hardly even seen one... But I'll post up all of that info. I'll also try to get Coog to post up here too, he has posted and sent pics about them and the 6 cyl variants on the yahoogroup and on pirate...
 

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quoting from the ih8mud.com thread...

This swap keeps coming up time and time again! Please, someone do it and document it so that I have some one's example to follow.

I have a 4BD1T and a 4BD2T that I am considering swapping into my FJ62 after I finish my SOA (might be a while at my speed). The 4BD1T's came in Isuzu NPR trucks from '86 to '91. They were turboed but not intercooled and were rated at 121 hp @ 3000 rpm and 232 ft-lb @ 1800 rpm. They use an in-line mechanically-controlled injection pump and are direct-injected. The 4BD2T is basically the same block as the 4BD1T but the head configuration is changed to indirect injection. The 4BD2T's came in Isuzu NPR trucks (also re-badged as Chevy and GMC) from '92 to '97. They were rated @ 135 hp @ 2800 rpm and 255 ft-lbs @ 1900 rpm. The 4BD2Ts were intercooled in addition to turboed and I suspect the intercooler was primarily responsible for the increase in hp and torque.

The latter (4HE1TC) engines increased displacement from 3.9 to 4.8 liters, went to an overhead cam configuration and went to electronic controls on the injection. They also swapped the intake and exhaust sides of the engine so they are opposite to that of a LC. These engines were rated at 142 hp for manual transmission models and 175 hp for the automatics.

My understanding is that the bell housings are not interchangeable between the 4BD and the 4HE series engines.

I've been following the various threads discussing installing these engines in LCs but have not come across anyone who has actually done one, although some claim that it had been done. No one seems to dispute that this might be a great swap.

Most people seem to want to mate the Isuzu engine to a LC transmission or to another transmission for which there are adapters to LC TC (ie NV4500). I would like to consider using the stock Isuzu manual 5-speed and mating it to the LC TC, possibly using the Toybox as an adapter. Not at all sure if this is feasible.

The MSA5D 5-speed fully synchro manual transmission that comes with a 4BD1T has a 5.67 1st gear and 5th gear is 1:1 (no OD). Everyone that I know that has experience with these transmissions say they are bullet-proof.

The down side of using the Isuzu transmission is 1) mating the output to a LC TC, 2) setting up a means of shifting as these are not top-shifted but rather use a series of external rods and levers to connect the transmission to the shift lever.

I'd love to see someone undertake this swap project and post their experiences here.
 

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I've got a 4BD1T and MSA-5P box in a range rover.

The boxes are very strong, but slow shifting (don't expect rally speed changes). I'm currently getting geared up to swap the MSA-5P for a MSA-5G which has a better gear spread. The 5P has a big gap between 3-4 where the 5G is more evenly spaced.

What made a massive difference to my engine was getting the crank and conrods balanced. There was about 27g difference in big end weights, as you can imagine it runs a whole lot sweeter with that sorted.

Recently I've increased my gearing to drop cruise to 2000rpm, saving around 10% in fuel compared to my old gearing of 2500rpm cruise.

Working on turbo issues at the moment.
Mine is a japanese sourced engine with an IHI turbo which is hard to find parts for (need a new compressor wheel). I have a 4BD2 turbo to try but no manifold yet and a VGT from an audi diesel which needs modified to work (vacuum signal).

My goal for this engine is 200hp with a broad flat torque curve and no black smoke. Shouldn't be too difficult.
 

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Dougal... great info

I am looking at a early 90's 4BD1T with a 5 speed attached right now.

what should I look out for. The Motor has a rebuild tag on it from Isuzu USA.
Coming out of a wrecked NPR truck.

the 5 speed is column shifttype ( or at least side shift configuation, not stick).. did they ever make a stick that would drop in?.. or do you have to stay with that?

Did you go a divorced trans case?

Berg
 

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I've got a 4BD1T and MSA-5P box in a range rover.

The boxes are very strong, but slow shifting (don't expect rally speed changes). I'm currently getting geared up to swap the MSA-5P for a MSA-5G which has a better gear spread. The 5P has a big gap between 3-4 where the 5G is more evenly spaced.......
I'm new over in this forum but couldn't help but notice your engine/transmission combo in your rRnge Rover. I have an '89 Isuzu NPR 4BD1T with a MSA-5D transmission that I would like to transplant into a FJ62 Landcruiser. I've been trying to find variation on the transmission as the MSA-5D poses two problems: 1) Adapting it to my transfer case and 2) The gear shifting is accomplished with a series of levers and bellcranks, similar to what you might find with a column-mounted shifter rather than having the shifter come out of the top of the transmission.

I'd love to find out more about your transmisiion(s).

How is the shifting set up on your transmission(s)?

Do you know if there is a similarity between the MSA-5P and the MSA-5D that I have?

Who makes these transmissions?

How is yours mated to the T/C?

Where are you located as we see very few diesel Range Rovers in the US?

Any more general information regarding these transmissions would be greatly appreciated!
 

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Dougal... great info

I am looking at a early 90's 4BS1T with a 5 speed attached right now.

what should I look out for. The Motor has a rebuild tag on it from Isuzu USA.
Coming out of a wrecked NPR truck.

the 5 speed is column shifttype ( or at least side shift configuation, not stick).. did they ever make a stick that would drop in?.. or do you have to stay with that?

Did you go a divorced trans case?

Berg
The gearboxes are all cable/linkage change as far as I know. Mine has a mongrel stick shift conversion out the top, but the best method is to hook up the cable change gear lever from a manual fwd car.

With an "isuzu" rebuild tag you'll be set, in my experience aftermarket parts for these engines aren't worth the pain. The genuine parts are well worth the small cost premium, in several cases the genuine parts are cheaper.

My transfer case (LT230) is held on with an adaptor system which replaces the back plate of the gearbox. I don't like that it that much. A semi-divorced setup would be best as you keep the intact gearbox and use existing bolts to hold it rigidly to the transfer case while keeping the box intact.

See if you can find the gearbox model, I have some ratios on paper.
 

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I'm new over in this forum but couldn't help but notice your engine/transmission combo in your rRnge Rover. I have an '89 Isuzu NPR 4BD1T with a MSA-5D transmission that I would like to transplant into a FJ62 Landcruiser. I've been trying to find variation on the transmission as the MSA-5D poses two problems: 1) Adapting it to my transfer case and 2) The gear shifting is accomplished with a series of levers and bellcranks, similar to what you might find with a column-mounted shifter rather than having the shifter come out of the top of the transmission.

I'd love to find out more about your transmisiion(s).

How is the shifting set up on your transmission(s)?

Do you know if there is a similarity between the MSA-5P and the MSA-5D that I have?

Who makes these transmissions?

How is yours mated to the T/C?

Where are you located as we see very few diesel Range Rovers in the US?

Any more general information regarding these transmissions would be greatly appreciated!

My reply to Berg covered several of your questions. I'm located in New Zealand, Australia is the other hotbed of range rover conversions, this engine was factory installed in some military landrovers in the late 80's and early 90's.

I don't have any info on the 5D gearbox, but I have ratios for the 5R, 5P and 5G. My 5G has different input and output splines to the 5P I have fitted now, but is otherwise a dropin replacement.
To my knowledge they are only an isuzu part, they could be made in japan, china or any other country but I haven't heard of them being fitted to anything other than an isuzu engine.
 

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....I don't have any info on the 5D gearbox, but I have ratios for the 5R, 5P and 5G. ...
According to the FSM, the MSA-5D is fully syncgronized 5-speed with the following ratios:

1st - 5.670
2nd - 3.415
3rd - 1.900
4th - 1.331
5th - 1.000
Rev - 5.680

When I pull the engine/trany, I will take some pictures and post them here.

I am unfamiliar with the LT 230 T/C. Is that a Land Rover case? Is the rear output shaft centered or offset?
 

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According to the FSM, the MSA-5D is fully syncgronized 5-speed with the following ratios:

1st - 5.670
2nd - 3.415
3rd - 1.900
4th - 1.331
5th - 1.000
Rev - 5.680

When I pull the engine/trany, I will take some pictures and post them here.

I am unfamiliar with the LT 230 T/C. Is that a Land Rover case? Is the rear output shaft centered or offset?
Those are quite different to my ratios. In my box 4th gear is straight through.

MSA5G,
1 - 5.788:1
2 - 2.998:1
3 - 1.594:1
4 - 1.000:1
5 - 0.776:1
R - 5.798:1

MSA5P,
1 - 5.788:1
2 - 2.998:1
3 - 1.735:1
4 - 1.000:1
5 - 0.776:1
R - 5.798:1

You can see the difference in 3-4th gears between the 5P & the 5G, the main reason for me wanting to swap.

The LT230 is a landrover/rangerover box (LT = Leyland Transmission) with both outputs offset to the right side and inline.
I managed to find a rare high ratio version (1.003:1 compared to 1.2:1) which has given me 2000rpm cruise at 100km/h.

You'll need some big tyres or a very high diff ratio to keep a 4BD1T happy at motorway speeds (if that's part of the plan).
 

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If anyone's interested in the bigger (5.2L) 4HK1-TC, the tranny ratios look promising (Never seen this engine, just speculating.) 190hp, 387 ft-lbs.

Isuzu Mzz-6U
1st- 6.369
2nd- 3.767
3rd- 2.234
4th- 1.442
5th- 1.000
6th- 0.782
rev- 6.369
 

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Between the 4BD1/2-T series and the 4HK1-TC was the 4HE1-TC at 4.8 liter. These were rated at 142 hp (manual trans) and 175 hp (automatic). These were overhead cam engines and had the intake and exhaust sides reversed from the 4BD1/2 series. I also heard that he bell housing ends of the blocks are different so, I assume, that transmissions would not be directly interchangeable.
 

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I managed to find a rare high ratio version (1.003:1 compared to 1.2:1) which has given me 2000rpm cruise at 100km/h.

You'll need some big tyres or a very high diff ratio to keep a 4BD1T happy at motorway speeds (if that's part of the plan).
Do you find that 2000 rpm is a good cruise rpm for the 4BD1-t? I've been playing around with different ratio/tyre size combinations for my FJ62 but don't have any first-hand experience with the 4BD1-T.
 

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Do you find that 2000 rpm is a good cruise rpm for the 4BD1-t? I've been playing around with different ratio/tyre size combinations for my FJ62 but don't have any first-hand experience with the 4BD1-T.
My fuel economy improved 10% by dropping from 2500 to 2000rpm. It also made the vehicle soo much quieter and smoother. It could be mistaken for a petrol at cruise now (but the idle noise gives it away).

The engine has plenty of reserve for pushing my rangerover at 100km/h at 2000rpm, raising the gearing has for me bought 4th gear high enough to use for overtaking at up to 120km/h.

Before then 4th gear would only pull about 105 km/h and I had to use 5th for overtaking, which accelerated noticably slower.

I used to be 100km/h in 4th was roughly 3300rpm, 5th was roughly 2500.
Now 100km/h in 4th is roughly 2800rpm and 5th is 2000.
 
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