hyper. vs . forged
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hyper. vs . forged
anyone even had bad or good luck with hyperteknic piston's. i am just courious they seem ok so far and i have ran them for 2 sesons and i also hit 7200 rpm a few tims so do i just have good luck or are thease pistons not so bad? i am kinda weiry about them i havent head much good about them?
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Hyperutes are, at best, an okay solution for those needing something slightly stronger than cast but cheaper than forged. Unfortunately, though, the hyperutes also have a bad habit of self-destructing if you have pre-ignition problems. They also will not stand up to repeated punishment much better than stock cast pistons will.
Forged is always better. If you are building a competition engine, or even a hot street motor, I don't think that you should use anything but.
Brad
Forged is always better. If you are building a competition engine, or even a hot street motor, I don't think that you should use anything but.
Brad
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Hypereutectic Pistons
I to used to think that forged pistons of the correct alloy were the strongest.
However think about this:
Hypereutectic pistons are cast and can run tighter piston to wall clearances. Also the ring package can be tighter. The pistons rock in the bore less than any other design. Thus they are more effecient.
Hypereutectic pistons can be made lighter than even forged pistons.
The hypereutectic piston casting process is changing and if not right now than real soon will produce a stronger piston that will survive 9000 RPM.
Most race engine builders are already looking at them.
Things do change.
However think about this:
Hypereutectic pistons are cast and can run tighter piston to wall clearances. Also the ring package can be tighter. The pistons rock in the bore less than any other design. Thus they are more effecient.
Hypereutectic pistons can be made lighter than even forged pistons.
The hypereutectic piston casting process is changing and if not right now than real soon will produce a stronger piston that will survive 9000 RPM.
Most race engine builders are already looking at them.
Things do change.
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thanks guys i was kinda curious cause i never hear much good about them but my speed pro falts hypers are going on there 3rd seson and liek i said 550 if not a bit more hp and 7200 rpms and still look like new i figured i am just lucky? or there not all that bad plus my motor is a quick revving motor beeing it is all roller but i am still kinda worried but i think i might run them again this seson stick money into the heads. like the old saying gose why fix if it aint broke but i am still up for advice
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From: New Jersey
LorenR is correct - Hyperteutectic pistons expand less in the bore, which means you can run closer tolerances, have a better seal, and have significantly less blow-by especially with forced induction applications where the extra heat and pressure often works their way past the rings if one isn't too careful.
This is because they are stronger.
The drawback to hypereutectics is they are more brittle than other forged pistons, therefore less tolerant of shock loads. Detonation is a shock load. The whole charge goes "poof". Normally, the spark plug sparks, and the flame flows quickly across the air/fuel mixture generating heat and expansion gasses to push the piston down. This happens very slowly, as compared to detonation. Also, detonation often occurs while the piston is moving up, rather than closer to top dead center, so there is a mechanical pressure behind the piston which increases the shock load "feel" during detonation.
Anyway, all that aside, against many people's advice I've run hypers in forced induction engines, one of them with some pretty wild boost figures.
This is because they are stronger.
The drawback to hypereutectics is they are more brittle than other forged pistons, therefore less tolerant of shock loads. Detonation is a shock load. The whole charge goes "poof". Normally, the spark plug sparks, and the flame flows quickly across the air/fuel mixture generating heat and expansion gasses to push the piston down. This happens very slowly, as compared to detonation. Also, detonation often occurs while the piston is moving up, rather than closer to top dead center, so there is a mechanical pressure behind the piston which increases the shock load "feel" during detonation.
Anyway, all that aside, against many people's advice I've run hypers in forced induction engines, one of them with some pretty wild boost figures.
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well guys i think you all just helped me make a very wise decision i decided to not touch my bottom end since i have a molly top ring and only about 10-15 passes on the motor passes i mean 300ft truck pulling and i had some issues getting the engine tuned so it only hit 5500 most of the time so buy not spending the exra cash on forged and hbeams since my ibeam sir egals seem to be working fine i will be able to stick more money into the heads. and possible replace the headers they r gettin kinda bad i had to patch the heck outta them due to a flywheel explosion 2 yrs ago thanxs again for all the advice and i am still up for more adive on any issue in cause no one has read my input ideas for a 460 i am trying to get alot of powed on a small limted budget have a good one and merry xs to all
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From: Folsom, Louisiana
Originally Posted by frederic
LorenR is correct - Hyperteutectic pistons expand less in the bore, which means you can run closer tolerances, have a better seal, and have significantly less blow-by especially with forced induction applications where the extra heat and pressure often works their way past the rings if one isn't too careful.
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