Material differences btween a NPR 4BD1T and a ex-army 4BD1?

**123rover50** · 23rd September 2017, 05:32 AM

Originally Posted by Bearman

Mate, I would be checking that ex army box out before you put it in the vehicle. All used boxes auctioned were removed for a reason. Every one I have pulled apart have had some problem, whether it be worn synchros, bent lock tabs on the input shaft bearings or transfer case problems.

You are right Brian. I will

**Dervish** · 23rd September 2017, 05:33 AM

Originally Posted by Vern

...my 4bd1t is up in the 650nm range...

Dyno readout please?

**Vern** · 23rd September 2017, 07:47 AM

Originally Posted by Dervish

Dyno readout please?

Sorry i don't have a copy, was what a mate with a dyno told me as he ran the car on his dyno whilst he was looking after my car when i was interstate. It also made 101.6kw at the wheels

**Vern** · 23rd September 2017, 07:50 AM

Originally Posted by Dervish

The MSAs have a larger gap between 3rd and 4th; and between 2nd and 3rd, and between 1st and 2nd?

Sorry but i don't find that it has, i have tried 2 different msa boxes, a 5g and a 5r and have found them both great, the only real differences i have found is in 1st gear.
Ratios feel closer than the lt95

**Fubar** · 23rd September 2017, 12:46 PM

Originally Posted by Vern

Sorry but i don't find that it has, i have tried 2 different msa boxes, a 5g and a 5r and have found them both great, the only real differences i have found is in 1st gear.
Ratios feel closer than the lt95

Header is offset one to the left...can't change it back.

LT95 109 Stage 1, 101, Range Rover thru ’83 V8 90/110 ’83 & ’84	LT85 All V8 90/110 ’84-’91	LT77/LT77S 2.5L & 200 Tdi ’84 thru ’93	LT77/LT77S V8 Discovery thru ’93 V8 90/110 ’92 & ’93
Fifth	N/a	0.80:1	0.83:1	0.77:1
Fourth	1:1	1:1	1:1	1:1
Third	1.51:1	1.436:1	1.507:1	1.40:1
Second	2.45:1	2.18:1	2.30:1	2.13:1
First	4.07:1	3.65	3.59:1	3.32:1

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

MSA-5G,
5.788:1
2.998:1
1.594:1
1.000:1
0.776:1
5.798:1

MSA-5P,
5.788:1
2.998:1
1.735:1
1.000:1
0.776:1
5.798:1

MSA-5R,
4.987:1
2.998:1
1.594:1
1.000:1
0.728:1
4.774:1

MXA-5R
4.987:1
2.870:1
1.594:1
1.000:1
0.728:1

**Vern** · 23rd September 2017, 12:52 PM

Originally Posted by Fubar

Header is offset one to the left...can't change it back.

LT95 109 Stage 1, 101, Range Rover thru ’83 V8 90/110 ’83 & ’84	LT85 All V8 90/110 ’84-’91	LT77/LT77S 2.5L & 200 Tdi ’84 thru ’93	LT77/LT77S V8 Discovery thru ’93 V8 90/110 ’92 & ’93
Fifth	N/a	0.80:1	0.83:1	0.77:1
Fourth	1:1	1:1	1:1	1:1
Third	1.51:1	1.436:1	1.507:1	1.40:1
Second	2.45:1	2.18:1	2.30:1	2.13:1
First	4.07:1	3.65	3.59:1	3.32:1

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

MSA-5G,
5.788:1
2.998:1
1.594:1
1.000:1
0.776:1
5.798:1

MSA-5P,
5.788:1
2.998:1
1.735:1
1.000:1
0.776:1
5.798:1

MSA-5R,
4.987:1
2.998:1
1.594:1
1.000:1
0.728:1
4.774:1

MXA-5R
4.987:1
2.870:1
1.594:1
1.000:1
0.728:1

From my experience, the 5g works great with a 1.003 transcase and 33" or smaller tyres, but i did find it just a fraction tall for towing on hills.

The msa5r works great with a 1.192 or 1.222 transcase and 33's or bigger tyres, even when towing.

I did find the 5g and a 1.222 tcase geared to low in particularly 1st and all the mid range gears. Hence me swapping in a 5r box, which i am very happy with.

**Dervish** · 24th September 2017, 06:56 AM

Originally Posted by Vern

Sorry i don't have a copy, was what a mate with a dyno told me as he ran the car on his dyno whilst he was looking after my car when i was interstate. It also made 101.6kw at the wheels

Bummer, was it long ago? Surely he still has the file?

**Vern** · 24th September 2017, 07:35 AM

Originally Posted by Dervish

Bummer, was it long ago? Surely he still has the file?

Yeah i can ask, was about a year ago, mate did his perentie as well which made 96rwkw.
It was when he first got the dyno so don't know if he was recording things as he was playing around with it.

**Red90** · 24th September 2017, 09:01 AM

Originally Posted by Vern

Sorry i don't have a copy, was what a mate with a dyno told me as he ran the car on his dyno whilst he was looking after my car when i was interstate. It also made 101.6kw at the wheels

I suspect you are mixing up wheel torque with engine torque. You can't have 650 Nm torque and only 101 kW. The math does not work.

**Dervish** · 24th September 2017, 10:25 AM

Originally Posted by Red90

I suspect you are mixing up wheel torque with engine torque. You can't have 650 Nm torque and only 101 kW. The math does not work.

Which math is that?

101kW ATW would be ~180kW at the flywheel, so as far as I can see it's plausible. Highly unlikely I have to say - in fact I would say impossible in this case - but not from those figures; from limitations within the injection pump. I'm no guru myself, but I know the people that have spent more time with 4BD1Ts on dynos than anyone else and I know that without making serious changes in the pump you aren't getting that power or torque. And I don't mean just adjusting the max fuel screw, although you would just about have to take it off and throw it away as part of the process as well. There's a limitation within the pump that I've never seen anyone else mention, so I doubt very much anyone is making significantly more out of 4BD1s than KLR do. There's a lot of armchair engineers plugging data into formulas and coming up with impressive numbers, but the real world isn't so simple.

To be honest, I think your mate (Damien) couldn't interpret the results his dyno gave him. Incredibly common even amongst people who operate them unfortunately.

But hey, I could be wrong. I suspect we'll never know.

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