Armored Humvees Powertrain

[Hummer Guy]

This question is mostly for the guys who driven the armored humvees a bit, how good does the 6500 Optimizer and 4l80e holds up and is it enough for a somewhat comfortable city and highway driving? I have a BRDM 2 which is not much heavier than an armored humvee, I think its about 8 tons while a completely armored humvee is around 5-7 tons from what I hear. I'm thinking of using this powertrain for it since it should fit in the relatively small engine bay plus it already has more power than the gasser that's already in it which makes about 140hp and less than 300ft Ibs of torque. Also, it would make getting parts far more easier

 

[MarkM]

The fully armored Humvees with the 6.5 turbo can't get out of their own way. Look into the 6BT 12 valve as it is capable of far more power and much more longevity. The Duramax would also be a great choice. They are much better power options for a heavier vechicle. Just my 02 cents but I'm sure many more will step in with the same conclusion.

Mark

 

[Hummer Guy]

The fully armored Humvees with the 6.5 turbo can't get out of their own way. Look into the 6BT 12 valve as it is capable of far more power and much more longevity. The Duramax would also be a great choice. They are much better power options for a heavier vechicle. Just my 02 cents but I'm sure many more will step in with the same conclusion.

Mark

That's what I thought but was hoping different, my only issue with the duramax is that I hear its a complex engine to work on and has quite a bit of electronics, and the 6BT issue is the length of the engine would be a problem, another engine I've looked at is a 4BT which seems to be capable of making decent power reliably

 

[Mogman]

I want one!

 

[Mogman]

If you are really cramped for space take a look at the little baby Duramax L6/3L makes

277 / 206.6 @ 3750 (HP/KW)

460 / 623.7 @ 1500

and no doubt that it can be turned up over 300 stock, dang thing can wind up to 5000RPM

 

[NDT]

4BT was going to be my suggestion. The turbocharged versions put out good power. The only thing the 6.5 engine belongs in is the HMMWV and that is debatable.

 

[87cr250r]

The 6.5 may be a better direct swap for a gas engine because it makes power like a gas engine. The Duramax and Cummins engines both run at lower speeds than the 6.5. Running the other diesels may require gear ratio changes to get the most out of the engine.

 

[Hummer Guy]

The 6.5 may be a better direct swap for a gas engine because it makes power like a gas engine. The Duramax and Cummins engines both run at lower speeds than the 6.5. Running the other diesels may require gear ratio changes to get the most out of the engine.

Great point

 

[Mogman]

The 6.5 may be a better direct swap for a gas engine because it makes power like a gas engine. The Duramax and Cummins engines both run at lower speeds than the 6.5. Running the other diesels may require gear ratio changes to get the most out of the engine.

Actually not true, at least as far as the baby Dmax, the 6.5L makes its max power at 3400 RPM, the baby Dmax 3750 RPM and it can twist 5K try that with a 6.5L, if you can adapt the 10L80 it has a top ratio of .64:1, the 4L80 .75:1 on top of being really cool to have it shift 9 times. other options would be the 6L80 at .67:1 and the same basic size as the 4L80 ( a little narrower actually)
My 6.6L Dmax/Allison replaced the 6.2L and 3L80 in my HMMWV and I am running about 1850 RPM at 60 MPH whereas I was running 2900 RPM with the 6.2L at 60 MPH so do not take the transmission out of the equation.

 

[MarkM]

The 4BT is a great motor capable of good power for its size. One thing on the 4BT is it is NOT a smooth engine at all
This can be rectified with a fluid damper harmonic balancer. Can put out more power easily over the 6.5.

Mark

 

[NDT]

The 4BT is a great motor capable of good power for its size. One thing on the 4BT is it is NOT a smooth engine at all
This can be rectified with a fluid damper harmonic balancer. Can put out more power easily over the 6.5.

Mark

Ha it’s going in a Russian vehicle, smoothness was not a priority for them in any way.

 

[87cr250r]

If you want a 4-cyl diesel that doesn't buzz, the John Deere 4045 engines have a counterbalance shaft and are smooth.

 

[Mogman]

If you want a 4-cyl diesel that doesn't buzz, the John Deere 4045 engines have a counterbalance shaft and are smooth.

A little low on all the boxes, RPM, HP, Torque and at 1000lb the perfect tractor motor.

 

[87cr250r]

The current emissions spec John Deere units are quite the little hot rods. We spin generators with them but they're cranking 150 horsepower at 1800 rpm.

The older engines use a Stanadyne DB4 pump. It shouldn't be much trouble to turn one up to 200 horsepower.

 

[Retiredwarhorses]

The 6.2-6.5 is so terrible they decided to use it for 39 years and continue to make it today…
Comparing 40yr old diesel technology to modern day is a lesson in futility.

 

[Mogman]

The 6.5L is a good fit for the military, one advantage is its pretty much immune to an EMP attack and it is simple enough for the average military mechanic to work on, it also has reasonable dependability in military service because most do not get many miles put on them.
You also have to figure in parts logistics within the military.
They also perform well in the military, the only competition are other slow vehicles unlike what the civilian owner faces out on the public streets.

When GM had the Detroit in production they had less than 5% of the light diesel market share.
To say the Detroit was under powered and undependable compared to the offerings from Ford and Dodge would be an extreme understatement, they were put out to pasture by the thousands, there were many shops that specialized in doing gas engine swaps into the Detroit powered trucks.
The year GM came out with the Duramax market share jumped to 30%.
While GEP has made some great improvements to the 6.5L it is more or less just putting lipstick on a pig.

 

[Hummer Guy]

What is the main issues with the GEP 6.5 and 6500 Optimizers? I know of the older 6.5s issues but it seems like all of it was fixed from GEP. The main thing I'm looking for is decent MPG and a slight power increase which it should do. It should be a 50HP increase and around 200 Ft Ibs of torque increase, I don't want to go insane on pwoer because of other issues it can cause, if I had to assume, the top speed shouldn't be much of an issue either since I believe the humvees are geared lower than what a BRDM 2 is, but I can be wrong about that

 

[87cr250r]

I bought a used 6.5 Optimizer with unknown miles. The truck was a 2001 and supposedly had 135k miles. The bearing inserts in the engine were 2004 so I'm certain the engine was replaced. It had some valve recession and the fire ring in the head gasket wore into the block. I had to strip the engine to get the top deck resurfaced.

 

[MarkM]

One motor I really like is the old 4-53T two cycle Detroit. A little noisy but a great motor and unfortunately the rpm band is no good for the HMMWV.

Mark

 

[Mogman]

One motor I really like is the old 4-53T two cycle Detroit. A little noisy but a great motor and unfortunately the rpm band is no good for the HMMWV.

Mark

I love the two cycles, I have two tractors with 4-53s in them and an old crane with a 4-71 (was running when parked LOL), I also have a rather rare 8V53 sitting in my shop, if I live long enough I would like to stuff it in something like maybe a T-bucket
That little V8 is awesome!
Not mine.