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Yes sir the blocks are lost foam castings .... I believe he meant to say the stock rods are powdered metal forgings .....
The LE5 is built on the older Gen-II block, with changes made over time. For instance, the connecting rods were forged steel, now they're melted powder (sintered metal)--despite what the book says, the LE5 does not have forged internals. The crank is cast, connecting rods are actually really good for being sintered, and the pistons are hyperteutectic (awesome technology). With the foamy appearance of the engine block and porosity (voids), I made the conclusion they went to sintered metal for the engine block also--I was wrong and the casting is lost-foam--my bad, and thank you @Batshot for the correction:
The block is cast from aluminum using a lost foam process. For applications ranging from 400 to 800 hp, a production block that has been screened for cracks, high porosity, or other imperfections and re-sleeved with a high-quality aftermarket iron sleeve is acceptable. This block can be flat-decked for use with the production head gasket up to 600 hp or an after-market mutli-layer head gasket up to 800 hp. For applications above 800 hp, the GM Racing modified block XGH679 is used. While some of the features of this block are not necessary at horsepower levels between 800 hp and 1200 hp, the features increase block longevity at any power level.
Real engine builders (who are not me) have said the foam casting process has known shortcomings in the LE5's production history, mainly resulting in thin walls on occasion which blow out under normal use, resulting in coolant leakage. Putting a forced-induction system on an engine that hasn't been checked for defects (see the above quote) can result in rapid decompression of one or more engine cylinders (your engine blows up).

It seems we got to the same result, but the correct way, which is important to understanding why things go wrong and how to minimize that from happening. Thank you again @Batshot for the correct information.

boom.jpg
 

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Was at Coleman Powersports today for a laser alignment and they are installing an Alpha turbo they just got in. Said they had to rewire the map sensor as Alpha shipped it differently this time. He showed me the MAP sensor. When I flipped it over I was surprised that they are still shipping them with the rubber hose add-on to the seal. All it is is a poorly cut rubber hose that they stack on top of the OEM orange ribbed seal. I immediately showed them the adapter DDM is making. The tech told me a story about the last Alpha turbo kit they did and how the customer brought it back multiple times for running rough. Each time the sensor was popping out. Keep a close eye one those sensors guys.
 

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It didn't even look that nice. Looked like they used side cutters and cut it at an angle. It had a "v" cut in to it. You could see the orange seal under it.
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That is a picture of a DDM 2-bar sensor ...... looks like they just cut a vacuum cap and stick it on ..


EDIT: however I believe you may have been talking about the "safety clip" DDM is making.
But it does put in perspective how all three major players deal with the different size seal needed for the 2-bar sensor installation differently. The most elegant is how Hahn mills the sensor to accept an aluminum sleeve that captures an o-ring. But then you are beholden to them for replacements and as I understand it the wait for parts is long. But then again its just a seal .... installed with care and lubricated first as instructed they all seat and all should be checked to make sure they have locked in to the clip that actually holds it in place. However the "safety clip" or other secondary positive retention is a great idea.
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Was at Coleman Powersports today for a laser alignment and they are installing an Alpha turbo they just got in. Said they had to rewire the map sensor as Alpha shipped it differently this time. He showed me the MAP sensor. When I flipped it over I was surprised that they are still shipping them with the rubber hose add-on to the seal. All it is is a poorly cut rubber hose that they stack on top of the OEM orange ribbed seal. I immediately showed them the adapter DDM is making. The tech told me a story about the last Alpha turbo kit they did and how the customer brought it back multiple times for running rough. Each time the sensor was popping out. Keep a close eye one those sensors guys.
I never checkt anything on my alpha turbo with 40.000 miles on it and still running strong
 

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Hold my beer and watch this!
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That is a picture of a DDM 2-bar sensor ...... looks like they just cut a vacuum cap and stick it on ..


EDIT: however I believe you may have been talking about the "safety clip" DDM is making.
But it does put in perspective how all three major players deal with the different size seal needed for the 2-bar sensor installation differently. The most elegant is how Hahn mills the sensor to accept an aluminum sleeve that captures an o-ring. But then you are beholden to them for replacements and as I understand it the wait for parts is long. But then again its just a seal .... installed with care and lubricated first as instructed they all seat and all should be checked to make sure they have locked in to the clip that actually holds it in place. However the "safety clip" or other secondary positive retention is a great idea.
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I'll try to explain better. The OEM MAP sensor has a orange ribbed seal on it. The Alpha modified sensor literally has a thin rubber hose that they cut poorly with side cutters and slipped it over the orange seal. I've attached a picture to show what the sensor looks like without any modification.
2017-04-24-19-45-45-.jpg
 

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Hold my beer and watch this!
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The supplied Alpha sensor has been shown several times in this thread .....

View attachment 121673
Ok, but the one I saw today had a "v" cut in it that went about mid way down. Just trying to explain what I saw so that others look out for it. That was the way Alpha supplied it to a Slingshot dealer. I would have taken a picture, but left my phone in the truck. I'll try and get shot when I pick up my slingshot.
 
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