6.5L Rumors...

[More Power]

For as long as there's been a 6.5, there have been rumors about what first GM and and now AMG was/is doing in their 6.5L engine development. Back in the mid 1990s we heard about a factory intercooler scheduled for introduction in the C/K pickups, we also heard about direct injection, aluminum cylinder heads as well as a range of smaller improvements. In one case, a TDP member's wife was on GM's Romulus Engineering team that was developing the DI heads. He was a gearhead, and told me all about what (he thought) was coming. There were running examples. Some years ago, I saw pictures of aluminum cylinder heads.

Earlier this year, I heard from a reliable source that AMG was developing electronic high-pressure common rail for the 6.5 that used DI heads and a variable vane turbocharger. I suspect this is based on the Bosch/Garrett system currently used on the Duramax. Combined with AMG's already great P400, the new fuel and turbo system would change a lot.

Jim

[Robyn]

My big question now is, what is it going to be used in.

It would seejm that the HMMWV is finished as the US Military is phasing it out as the universal people mover.

To redesign an engine for common sale to the public for use in 15-20 year old rigs can't be profitable.

Where will these engine find a nitch. Boats and retro fit applications ???

Currious

Missy

[KrisL]

While it would be really sweet to have that setup. I'm kinda wondering the same as Robyn, Why now? Would be really cool though

[trbankii]

Add another vote for "drool-worthy yet confused as to application" here as well.

[Robyn]

The info at the AMG site speaks of gen sets, construction equipment and other applications.

Overall though this engine can be used for a lot of stuff.

Construction.
Gen sets.
Marine use
Hmmmm maybe stuff one in a crop duster plane
Snow groomer???, should work fine.
The fact that the engine will marry to a buttload of different GM bolt pattern trannies is not at all a bad thing either.

Loads of retrofit applications.

Jeeps and other small 4x4's

Just still seems off the wall to redo this engine design NOW after sooooo many years.

Missy

[6.5 Detroit Diesel]

please please please please please make this!!!! i would love to get my hands on a DI set of heads. new turbo and fueling system.

[HH]

Jeeps and other small 4x4's


Missy

Have a 6.2 in my Jeep Grand Cherokee.

[JohnC]

Hmmmm maybe stuff one in a crop duster plane

WAY too heavy...

You can get almost 700 shp from a PT6 that only weighs about 315 lbs.

If you want to go to about 500 lbs you can get as high as 1650 shp.

[Stratosurfer]

WAY too heavy...

You can get almost 700 shp from a PT6 that only weighs about 315 lbs.

If you want to go to about 500 lbs you can get as high as 1650 shp.

Yes but that turbine will move some fuel: at 700 SHP I'm thinking about 100+ gallons per hour. Diesels are coming to the General Aviation market, they're just too heavy as you say, currently. I don't ever see a 6.5 in an airplane, nor a Cummins 5.9 either, even with maximum move to aluminum they remain too heavy. I know you were kidding Missy, however being a General Aviation pilot I follow the trends, and diesel is probably the future as 100LL fuel is being phased out.

[JohnC]

Bottom line: A cast iron engine won't fly...

[Stratosurfer]

Bottom line: A cast iron engine won't fly...

Well said!

[Robyn]

John C

Here is a link to a very interesting item. http://www.alternate-airpower.com/

I have seen one of these conversions on a crop duster. A local guy has a 502 Chevy in a really cool duster using one of these adapters.

Damned thing is awesome to say the least.

Big O'll 4 blade prop on the sucker and he can almost hang the plane on the prop.

The GM Iron engines may be heavy, but someone is making it work.

The 460 ford is also used.

Anyway, to see DI heads with a common rail system on the 6.5 would be way cool.


Missy

[Stratosurfer]

John C

Here is a link to a very interesting item. http://www.alternate-airpower.com/

I have seen one of these conversions on a crop duster. A local guy has a 502 Chevy in a really cool duster using one of these adapters.

I have followed these gas V8 conversions for years and they do have some success. I believe most of them are aluminum blocks and maybe even aluminum heads.
Diesels are coming to general aviation quickly. The blocks are going to be interesting: composite/metal mixtures. Very exciting, seeing as I make my own Biodiesel.

[ThePIGSmith]

It would seem that the HMMWV is finished as the US Military is phasing it out as the universal people mover.

While the gum-mint maybe phasing out the HMMWV, they are way to many of them in all branches of the service to shove them out overnight.

My guess there will always be HMMWV for other duties, just like there are CUCV still in limited service.

Which means, there maybe a market for upgraded HMMWV

Maybe if there were a more powerful and fuel efficient 6.5, maybe the gum-mint might wanna hang onto a few HMMWV?

Okay, this is a stretch and we need to keep in mind this only a rumor.

[rustyk]

Bottom line: A cast iron engine won't fly...

In WW II, the Soviet Union had the Petlyakov Pe-8 heavy bomber which had diesels (unreliable) and later gas engines.

[X15F]

I have a couple of ideas about direct injecting the 6.5, spray welding would be a part of it. The first step is to use spray welding powder with oxy-acetylene to fill in the pre-cup pocket completely. Then just outside the valve cover lip bore a hole down thru the head at an angle to be as close to the center of the cylinder as possible. I'm pretty sure this will go through the water jacketand will involve more spray welding powder. A piece of black iron pipe could be cut to fit into the newly bored hole and spray filled/welded in place. The new injector area could then be machined to accept either new Dmax type injectors or Stanadyne pencil type mechanical injectors. The Stanadynes now have soft start ramps in the pumps and rate shaping available. The soft ramp is similar to the pre ignition fuel pulse in the Dmax system. Using a Stanadyne system may not be as efficient but would probably be easier to come by and more cost effective. The glow plugs would be put in close proximity. Now there is the issue of Pistons for direct injection. The Dmax has the same bore but there is a difference in the pin to piston top aka compression height. 6.5 pistons have a 2.115 CH and the Dmax has a 1.961 CH. For efficient combustion the pistons have to be close to the deck. Having TDC below deck height costs efficiency and power. This would involve stroking the crank an additional .144" or 3.6576mm new displacement would be 410CI or 6711cc. Dmax injection system or Stanadyne mechanical injection are the question and the spray welding of the heads.
What are your thoughts on this? I think it could be done for a reasonable amount if most of the work including the welding was done by the owner. As far as the crank goes I know they can be built up, offset ground and re-nitrided. Not sure what this would cost. Is it possible, feasible?

[phantom309]

Bottom line: A cast iron engine won't fly...

Not entirely true,. i know of a large v12 engine that powered a few planes that flew,.
The liberty V8 seemed to do ok,.

[phantom309]

Bottom line: A cast iron engine won't fly...

Not entirely true,.V12 merlins and griffons were all cast watercooled motors,.


The liberty V8 seemed to do ok,.


they are still flying today,.

nick

[DmaxMaverick]

I have a couple of ideas about direct injecting the 6.5, spray welding would be a part of it. The first step is to use spray welding powder with oxy-acetylene to fill in the pre-cup pocket completely. Then just outside the valve cover lip bore a hole down thru the head at an angle to be as close to the center of the cylinder as possible. I'm pretty sure this will go through the water jacketand will involve more spray welding powder. A piece of black iron pipe could be cut to fit into the newly bored hole and spray filled/welded in place. The new injector area could then be machined to accept either new Dmax type injectors or Stanadyne pencil type mechanical injectors. The Stanadynes now have soft start ramps in the pumps and rate shaping available. The soft ramp is similar to the pre ignition fuel pulse in the Dmax system. Using a Stanadyne system may not be as efficient but would probably be easier to come by and more cost effective. The glow plugs would be put in close proximity. Now there is the issue of Pistons for direct injection. The Dmax has the same bore but there is a difference in the pin to piston top aka compression height. 6.5 pistons have a 2.115 CH and the Dmax has a 1.961 CH. For efficient combustion the pistons have to be close to the deck. Having TDC below deck height costs efficiency and power. This would involve stroking the crank an additional .144" or 3.6576mm new displacement would be 410CI or 6711cc. Dmax injection system or Stanadyne mechanical injection are the question and the spray welding of the heads.
What are your thoughts on this? I think it could be done for a reasonable amount if most of the work including the welding was done by the owner. As far as the crank goes I know they can be built up, offset ground and re-nitrided. Not sure what this would cost. Is it possible, feasible?

I like the idea of a DI 6.5L. In fact, it's an old subject, and has been discussed at length here before. The problem is practicality. There are other DI platforms already in service and readily available.

Your proposal does have merit, IMO, but is well outside the realm of practical. It would be more practical to have heads cast w/o the pre-chambers, resulting in a more reliable base for heads. Or, much more simple than welding/filling the head, a solid pre-cup could be made, and fixed permanently into an original head. All that welding on 6.5 heads would certainly lead to metallurgical and thermal issues, which are an existing concern, under the best of conditions. You'd be better off using J-B weld.

There are methods to adjusting the deck height of piston crowns currently being used. Wrist pin repositioning, redesigned pistons (off the shelf items), deck milling, shimmed gaskets, etc. The 6.5L is already a zero-clearance engine, so decreasing the deck height beyond recommended would certainly require a redesigned piston crown, in any case. 6.5L piston crowns are currently designed for use with the precombustion chamber, with a corresponding combustion chamber (Ricardo Bowl), again requiring a new piston design.

Using an HPCR fuel injection system would also be well outside the realm of practicality. This is already the most common weakness among the engines using it. The existing 6.5L distributor-type injection system would be much more practical, and wouldn't require the design of a new HP pump, and the plethora of electronics involved (the second most common weakness among the engines using HPCR).

[Robyn]

AM General/GEP has been fiddling with a set of direct injection heads for the 6.2/6.5

Last time I spoke to one of the guys with GEP, he spoke of the ongoing work and the likelyhood that a set of common rail heads would be worked with.

The plan of spray welding up a set of existing heads is IMHO workable "maybe" but these castings are shakey anyway.

Better to start with a fresh hunk of iron and build in some good reliability while your at it.

The Plan at GEP was to use the P400 with all its new goody yum yums (Block with girdle and forged crank) then add some common rail direct injection heads.

This would really bring the 6.5 into the 21st Century.
The statement was made that once completed, the resulting engine would be ONLY simlilar to its infamous ancesters as we know them.

The cranks would still be the same and probably interchangable as would the block.
Buttttt there was also the mention of changing the block deck bolt pattern some as well as other changes to improve clamping ability of the head bolts.

If this comes to fruition, the resultant engine will probably share little with its ancestry other than the Cubic displacement.

My real question is WHY????

hd this stuff been done back when the 6.5 was still on the cad cam machine, life might have been far better.

The 6.5 was a cheap way to get slightly more power and still keep with a cheap to build platform.

To reinvent to the wheel so to speak is all that a common rail 6.5 P400 would be doing.

The Duramax is by far a better engine and Proven, and available right now.

AMG/GEP may simply be trying to add some life to a dying product line.
IMHO these venerable old beast have just about reached their place in the history books, right along with the Old ford Y blocks and others that served us and faded into the swirling mists of time.

I hate to toss cold water and the 6.5 campfire, but still, why go there.

The mainstream manufactures are not going to use this engine again, and the numbers of vehicles that currently have a 6.5 are fading fast due to normal attrition, leaving a fast dwindling market place.

The HMMWV as mentioned will be around for a while longer but the huge number of new stuff being built is gone, at least for the US Military it is.

As an "OFF THE SHELF" crate engine to power various things from boats to gen sets, its fine, but the market "Bandwidth" is very narrow as compared to the use it once saw with GM and AMG.

Ahhhh Well such is life.

Missy