German HEMI....?
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German HEMI....?
Hmmm, I didn't know that Porsche released a Hemi. Learn something new every day. 
http://cgi.ebay.com/ebaymotors/Porsc...fCarsQ5fTrucks
http://cgi.ebay.com/ebaymotors/Porsc...fCarsQ5fTrucks
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From: Atlanta, GA
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
'91 928GT S/C
475hp/460lb.ft
Dan
'91 928GT S/C
475hp/460lb.ft
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From: 3rd Rock From The Sun
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?
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?
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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.
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.
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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.
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.
Race Car
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From: Atlanta, GA
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
'91 928GT S/C 475hp/460lb.ft
Dan
'91 928GT S/C
475hp/460lb.ft
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From: Somewhere, NC
)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