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Newest hmmwv- NXT 360

Discussion in 'GM 6.5 Diesel Engines' started by Will L., Jun 13, 2018 at 11:46 AM.

  1. JayTheCPA

    JayTheCPA Well-Known Member

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    Interesting. It was introduced in Paris. Am surprised that AMG did not have it climb a mound of fromage or put a bottle of wine on the bonnet :)
     
    MrMarty51, Will L., KrisML and 2 others like this.
  2. schiker

    schiker Well-Known Member

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    Pretty impressive. Especially the upwards of ~100 mph top speed. Hope they get lots of customers to keep pumping out engines and improvements.
     
    MrMarty51, Will L., KrisML and 2 others like this.
  3. Will L.

    Will L. Well-Known Member

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    Boulder City Nv
    So -p400, electronic ip, hvlp turbo, 6L85E trans. And some 20” wheels I actually like.

    Wondering how they did the ctis because you can’t see air lines from center going out like old style. The only problem with the old ctis system was crappy fittings they used.

    Now about the price tag...
     
    MrMarty51 likes this.
  4. JayTheCPA

    JayTheCPA Well-Known Member

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    Jun 13, 2011
    Annapolis, MD
    This one looks like it is for the non-US market, so your money is probably no-good ;)

    And with that, perhaps Leroy will get the go-ahead for overseas sales :)
     
    WarWagon, MrMarty51 and Will L. like this.
  5. Will L.

    Will L. Well-Known Member

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    Between his and the “Humvee C series” being sold in China, I just hope they sell more parts here in the US for citizens.
     
    MrMarty51 likes this.
  6. ak diesel driver

    ak diesel driver 6.5 driver

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    alaska
  7. Will L.

    Will L. Well-Known Member

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    Boulder City Nv
    Hmmwvs never had an electronic ip before. I read something about emp proofed electronic injection.

    But this also wouldn’t be the first bit of misinformation out on updated hmmwvs.

    Last I knew was a db4 going onto p400’s, but if them boneheads would learn from long term users that know it instead of asking military mechanics that got their training from the people that later ask what is best causing cyclic theories- they would have stuck to the db2s that are proven most reliable, longest life, and most power available. SMH. Sometimes wish I had stayed in the loop with the 6.5 decision makers.

    Imagine if they were to have p400 heads done in a cnc with Chris’s flow capability and coatings. Then spent some time on a VVT like the dmax like the 2 brothers did. Then imagine the db2 being built to performance specs like some of the real pump builders could do like ol Scott from J&S.
    Nay sayers that stuff would never happen, but I remember when coated crankshafts were never gonna happen. It isn’t like they are tryin to produce the golume GM did. Add a couple machines and few more people in production line and add maybe 3 days to each build for another 100 hp and 200 torque, and get more engine cooling and longer, more reliable life to boot.
     
    Jaryd and MrMarty51 like this.
  8. JayTheCPA

    JayTheCPA Well-Known Member

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    Jun 13, 2011
    Annapolis, MD
    Without seeing the torque numbers, it is tough to tell seeing as I got about the quoted hp number with a stock ULSD DS4.
     
    MrMarty51 likes this.
  9. Dullahan

    Dullahan New Member

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    Jun 6, 2018
    USA
    I know you've done a lot of work with hood scoops on these trucks, what are your thoughts on the one they're using here?
     
  10. Will L.

    Will L. Well-Known Member

    7,546
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    Jan 25, 2013
    Boulder City Nv
    222DF607-E819-4EAD-BC51-EAEB5E688DDF.jpeg

    They made changes to the front end- original was newr flat at the blue arrow. The extended front grille, which has since been changed to this version is slanted enough that maybe it changed the aerodynamics of it that this is a good set up. Really hope they were smart enough to have the coolant heated up like we did and run the fan like we did all inside a wind tunnel.

    The best design that worked on the old hood had the front edge just past flush with the front end, not back or tapered like the green arrow points now.

    Also the height of it is much lower, maybe why they tried opening up the front and tapering the sides so it could pull air in easier at the 30-50 mph range. The best height was roughly 1.5” high measuring vertical from the rear of the top grille (closest part open newrest the wind shield). Then the top piece was parallel to the ground, not tapered to match body at all, so it would catch 100% of the air to the top of the scoop and create a higher pressure at the back of the scoop on he inside. It also allowed plent of air to be drawn in when zero head wind is present.

    Side walls were vertical. It looks like the rear wall is the same angle as ours.

    The red arrow shows the basic airflow that occurs. Up the hood, up the windshield (yes in rain at higher speeds the water drops goes straight up in many places on the windshield). The air going over the roof creates a pocket and forces the air bouncing upward off the windshield foreward towards the upper radiator grille. (Just like riding in the bed of a pickup close to the cab- how the wind goes exactly backwards of what most people think it would do). When the headwinds speed gets up to modern freeway speeds (above 55) there is a literal wall of wind blocking air from coming into the top grille. The faster you go, the bigger the air blockage gets. So the top plate of the hood scoop stops the air pocket from getting to the opening. That allows the incoming air to be drawn into the stack.

    An interesting thing is most of the air coming in keeping it alive is from the front grille. But with the top grille wide open, a lot of the incoming air that goes through the front grille goes over the radiator and up out the top of the top grille. It just skips over the radiator like you imagine it does over a sloped hood.

    That is also part of how the scoop top coming all the way foreward helped. By creating no exit point, all the incoming air from the front grille is forced through the lower (front) half of the stack. Then the air that got trapped by the scoop gets shoved to the back of the scoop, and by having the top flat (we tried angles of corse) that air curled downward of the back angled plate through the top (rear) of the radiator. That part was actually key, because getting the most cooling air tk go through the hottest part of the radiator made the best temperature differential.

    I know when Bill Heath designed his scoop for Hummers He told me it was later redesigned by the hummer parts sales parter he was working with for better aesthetics. He said the testing showed his original worked about twice as good. When he described it to me dimensionally, it made sense. This scoop is similar to the redesigned one that He worked on, and since He said it was about half the performance... well... I am not convinced they actually put this hmmwv in a wind tunnel, compensating for engine fan, front tire air disturbance, etc.

    I hope they did. I am guessing this new one is also using a gfd with the larger radiator and 24” (ish) fan against the radiator like it should be. Also hope they corrected the radiator core pattern away from the 1920 design of inline cores for the staggerd and dimpled ones.

    It would be nice to see this in person and even talk with one or some of the folks that designed this. For interest in learning and incase there is anything I can share. Then also to put a bug in their ear about selling parts to us average folk, and congrats to the individuals that took what imo is a good platform and stepping up its game.
    Anytime a super capable off road, upArmoured rig can weigh over 15,000 lbs, and do 100 mph- oh yeah!
     
  11. Dullahan

    Dullahan New Member

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    Jun 6, 2018
    USA
    Great info, thanks! This part caught me by surprise:
    It makes me wonder, if the upper grille could be closed off at speed, with a Venetian blind type of setup rather than fixed grille bars, would it make a noticeable difference?

    It also seems most scoops, unless the back end were horribly designed, would block the high pressure air at the base of the windshield (red arrow), and provide at least a little improvement. The remaining performance would be from a combination of good flow through the scoop into the stack, and ram air effect - the latter working at it's best like you had it, with the front of the scoop even with the front of the hood (no real boundary layer issues). Am I on the right track or barking up the wrong tree?
     

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