hypereutectic pistons
#1
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hypereutectic pistons
whats the diffrence between forged and hyperetectic pistons?are they the same as a cast piston?i was told to stay away from them in a marine applaction.
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Hypers are cast pistons with a hardened coating for a slight increase in strength over cast. I believe they can be brittle and crack under heavy stress. They are lighter than forged but now nearly as strong.
They are no substitute for forged pistons in a motor over 450hp
They are no substitute for forged pistons in a motor over 450hp
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Hypers are cast pistons with a hardened coating for a slight increase in strength over cast. I believe they can be brittle and crack under heavy stress. They are lighter than forged but now nearly as strong.
They are no substitute for forged pistons in a motor over 450hp
They are no substitute for forged pistons in a motor over 450hp
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Yes, more silicone in the alloy. Makes them swell less under heat. I ran them for many years in perf marine engines, the last few in blower motors. They performed extremely well. The trick is to not get into detonation with them as they are more brittle than forged. They will break apart destroying an engine where a forged piston under detonation will blow a hole in the piston with often little damage to the rest of the engine. That is why they are often not recommended in perf marine engines. You really need to know what you are doing to make them work well in hipo marine applications.
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I have a 454 Mag efi motor that was rated at 385hp. I had my engine rebuilt 2 yrs ago and know the engine builder used the hypereutectic pistons in the rebuild (we called 5+ places and NO ONE had the forged pistons in stock). I have no interest in ever putting a blower on my motor and was told that these would work perfectly and be much better than cast. I hope what I was told is true. I really wanted to stay with forged but didnt want to wait a month to get the motor put back together.
So far Ive put about 80 hours on and she runs strong...
So far Ive put about 80 hours on and she runs strong...
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People like to blame hypereutectic pistons for failures on 496ho engines that were supercharged. The source problem is rarely with the piston and usually with the lack of ability to properly tune the fuel curve with the fuel injection.
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Yes, more silicone in the alloy. Makes them swell less under heat. I ran them for many years in perf marine engines, the last few in blower motors. They performed extremely well. The trick is to not get into detonation with them as they are more brittle than forged. They will break apart destroying an engine where a forged piston under detonation will blow a hole in the piston with often little damage to the rest of the engine. That is why they are often not recommended in perf marine engines. You really need to know what you are doing to make them work well in hipo marine applications.