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German HEMI....?

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Old 09-12-2010, 10:52 PM
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ALKada
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Default German HEMI....?

Hmmm, I didn't know that Porsche released a Hemi. Learn something new every day.

http://cgi.ebay.com/ebaymotors/Porsc...fCarsQ5fTrucks
Old 09-12-2010, 11:07 PM
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jeff spahn
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Of course it is a hemi. Just look at the shape of the end of the screwdriver handle. That little rounded part there, that's a hemi.
Old 09-12-2010, 11:07 PM
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dprantl
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The 928 engine has hemispherical combustion chambers, so it is accurate to call it a "Hemi". These days, certain US auto manufacturers are using the term for their bogus marketing campaigns.

Dan
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Old 09-12-2010, 11:18 PM
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ALKada
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Old 09-13-2010, 12:51 AM
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Ethre
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Saw that one too. Same thing as people selling their "powerstroke cummins".
Old 09-13-2010, 01:02 AM
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Erik N
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Originally Posted by Ethre
"powerstroke cummins".
Say what?
Old 09-13-2010, 01:19 AM
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Diesel engines for pickups. Ford's brand name for their recent engines has been "Powerstroke Diesel - PSD". Dodge uses a motor built by Cummins.
Technically though, every engine has a power stroke - so its not entirely inaccurate to call a Cummins motor a Powerstroke. Very deceptive though.

On the otherhand, if they advertise it as that, it must be the best of both worlds, right?
Old 09-13-2010, 01:27 AM
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Erik N
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Originally Posted by Ethre
"powerstroke cummins".
I will positively NOT say, "that's what she said"!
Old 09-13-2010, 03:56 AM
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928mac
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Originally Posted by Erik N
I will positively NOT say, "that's what she said"!
ROTFLMAO
Old 09-13-2010, 04:09 AM
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Speedtoys
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Originally Posted by Ethre
Saw that one too. Same thing as people selling their "powerstroke cummins".

Never said in a truckstop successfully, twice.

1) What's that Peterworth?
Old 09-13-2010, 09:53 AM
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hacker-pschorr
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I suppose we are about due for another thread on this topic, Greg must not be up yet

The 4-valve 928 head has a Pentroof with the spark plug in the middle. This is NOT a HEMI.

Very common area of confusion.


This is what a true HEMI head looks like, a true "half circle" which is where the name comes from.


Old 09-13-2010, 10:12 AM
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dr bob
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I think the original patent on the hemispherical combustion chamber belonged to an engineer named Maybach, at the time doing work for a Mr Daimler. Needless to say, that patent protection has long since expired. The "Hemi" name is trademarked and protected property of Chrysler. They can continue the trademark protection for as long as it has value.

Meanwhile, a true hemi is not quite the perfect chamber shape. The slightly pent-roofed chamber is better for several reasons related to gas flow and flame propogation, making it easier to manage spot tema and therefore NOx generation. Think Semi-Hemi and you'll be on the mark. It's what Chrysler really sells these days anyway.
Old 09-13-2010, 10:51 AM
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blown 87
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The 928 is a lot of things, but a Hemi is not one of them.
Old 09-13-2010, 12:32 PM
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Hmm, I have heard people refer to the Penta-roof design as a "Hemi" design as well, since that is what I think Chrysler is referring to when they say "Hemi" anyway... regardless, the 928 is like a Hemi++, since its design is better. Does anyone have an internal pic of the Dodge truck engine?

Dan
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Old 09-13-2010, 02:25 PM
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Originally Posted by dr bob
The slightly pent-roofed chamber is better for several reasons ... Think Semi-Hemi and you'll be on the mark.
When I first got my 928S4, I had more than a few remarks about my engine being a HEMI from JDM Ricers and American Muscle-heads alike... so I put a 'HEMI' badge on the back for grins (and to keep them guessing). Needless to say, I got razzed for it -with Erik & Greg being the main instigators (we're all friends now )

Take a look at these pics & you will see the "Real HEMI" is actually a pent-roof 'Semi-Hemi', and how a novice could call the 928S4 engine a hemi...

In order:
1.) Chrysler 426c.i. Hemi outward appearance (MOPAR ENGINES: Speed Secrets & Racing Modifications; c.1989; pg.387)
2.) Chrysler 426c.i. Hemi cylinder head cross-section (MOPAR ENGINES; pg.405)
3.) Chrysler 426c.i. Hemi valve gear layout (MOPAR ENGINES; pg.419)
4.) Porsche 5.0L (302c.i.) 32V outward appearance
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