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iTrader: (1)

I picked up a set of Mahle -9CC (PN LS1314903I09) pistons awhile back and been wondering about what effects having the dome coated would have on the overall strength of the 4032 alloy?

I know a few on here have had issues with this alloy piston on an FI application, which is exactly the situation I am trying to avoid. That said I hear that coated pistons retain their rated strenth even at extremely high temperatures whereas uncoated pistons do lose strength value aka rockwell hardness.

So the question is, has anyone coated and used Mahle's in an FI application 15-20 PSI? Results?

If it has not been done, I would certainly like to hear from all the chemists and scientists on here as to the why's or why not's to this concept.

Given this is my 3rd engine going into my GTO, I will most likely be going with an iron block 403, but since I had this stuff laying around thought the discussion might be interesting in any case.

JPH

iTrader: (2)

The Mahles already have a coating on them, but the crown area could be redone in another coarting if you wanted. I have used these in some FI applications, but only up to 10lbs. of boost so far with no issues. I would rather you use a #2618 material piston imo.

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iTrader: (1)

I was thinking it was just the skirts that were coated??

I agree with your assesment, the pistons would probably be best suited for a maggie installation. Just seems a bit strange to me that a forged piston is not any more reliable than the OEM casts have proven over time. There are many high 500's even a few low 600's HP motors running the cheapie OEM castings. Granted there are also more than a few OEM's that broke ring lands well before hitting those numbers.