Hypereutectic vs. Forged

[Hotrod]

Can someone explain what each of these are and when is the best time to use them.

[Italian LX]

The hypereutectic pistons are a cast piece and usually lighter (for the same amount of money spent); however, they are also weaker and not good in high horsepower application especially when boost is involved.

[coupe]

"Hypereutectic" is a term used in metallurgical engineering to describe a "phase" of one of the elements in an alloy metal. It has to do with the actual molecular structure of the material being in a certain "orientation," if you will.

Hypereutectic Aluminum is a lighter, stronger castable aluminum. It is machined to much tighter tolerances than forged and doesn't expand as much, so you can set up tight from factory and it will last long but yet be very cost-effective. That's why OE is all hypereutectic now (including LS1).

Alot of people are afraid of hypereutectic pistons (ie: hypereuplastic, hypereucraptic, etc.), but it's all a bunch of heresay...like alot of the internet. I would not hesitate to put 500 hp through them on a 5.0L mustang in the least. :nice:

[joker]

:jester:

[Dale McPeters]

Alot of people are afraid of hypereutectic pistons (ie: hypereuplastic, hypereucraptic, etc.), but it's all a bunch of heresay...like alot of the internet. I would not hesitate to put 500 hp through them on a 5.0L mustang in the least. :nice:

Yes, hyper pistons are just as good as forged pistons.

So if you want to build a good engine, do it right, and do it cheaply. There is no sense in spending money on forged stuff when you could put it towards something more worthwhile, like trips to Chucky Cheese.

:unsure:

[QWKSNKE]

I'll agree that hyper pathetics can handle similar power that forged can but one slip of detonation in a power adder car will cause them to go.

I made 525rwhp on my oem hyper pistons 2 years ago. One bad batch of gas killed #8 piston though. In my opinion they cannot handle the pressures in a forced induction car like forged can

[1sicklx]

In my opinion they cannot handle the pressures in a forced induction car like forged can

:agree:

[coupe]

...when is the best time to use them.

For a budget street/strip motor, you will be fine with hypers (like the keith-blacks). For something serious, that you intend on hard-use with a power-adder, Go ahead & put some forged in there. Forged pistons have come a long way themselves lately too. ;)

And regarding why the performance aftermarket offers Forged (ie: DSS), it's mostly because of the bad reputation that hypereutectic gets. :yup: Hypereutectic would do just fine for the average street-strip car. Find out what kind of numbers LS1's can make with hypereutectic pistons. I believe BarryD (turbomustangs.com) has run multiple 10's with twin-turbos...on hypers. :P And at Steele too (the fox hatchback from GA).

[Italian LX]

Comparing things to what other people do can only go so far. Sure, anything can be done and some people can get away with stuff like that, but that doesn't mean you should recommend other people to go that route.

It's similar to the IRS at the drag strip senario -- there are guys out there that run 10's and lower with slicks in an IRS Cobra, but I wouldn't recommend everyone to get some track tires and beat on their suspension.

Hell, I wouldn't recommend anyone put nitrous on a 300,000 mile short block, but I'm having pretty good luck with it. :P

[joker]

:jester:

[QWKSNKE]

. Therefore the hyper pistons are not recomended in high powered applications. Turbo and supercharged applications in paticular because the higher compression tends to better facilitate detonation. Now while some may say that detonation or lack there of is all a result of tuning, detonation cannot be completely eliminated in most street driven applications.

.

All of the above is very true.


I am confused now though. Earlier in the thread you and coupe both said one was as good as the other and now both of you are saying not :think:

[coupe]

:nono: You guys have at it. I'm through.

I answered the original question. We all know when to use forged. :nice:

[joker]

:jester:

[Dale McPeters]

:unsure:................:think:


:D

[Disney Lincoln]

For most of your mild NA street engines, a hyper piston will be a good pioece. Their low cost, increased strength (over standard cast), and stability make them good pistons. I wouldn't recommend them for anything that may go higher than 450hp though. If you are planning to boost it, rev it over 6500, or hit it with nitrous, then go ahead and step up to forged.

I typically put forged in everything I build. It's low cost piece of mind.

[joker]

:jester:

[TheJeanyus]

Yes, hyper pistons are just as good as forged pistons.
I wouldn't go quite that far. :think:

They are decent pistons up to around 500 rwhp IMO. Beyond that, you're gonna need forged pistons. If I were looking for a Fox for a build up, I'd look for one with forged pistons just for insurance. Of course, if you're looking for much over 500 rwhp you're going to need a block and be building an engine anyway, so it doesn't really matter.

[slvrbullit]

I jut dont see why anyone would put hyper pistons in a motor that is being built.

budget.

They really dont cost that much, and like Disney said, it is a low cost piece of mind.

A good set of forged pistons from a well know company cost 2 to 3 times as much as a hyper piston.

[slvrbullit]

And please from take the "who's smarter than who penile contest to PM's or email"

Thank you.

[joker]

:jester:

[slvrbullit]

A set of Keith black hyper pistons will run $250 to $300. A set off dss forged pistons run $550. I just dont see where a couple of hundered bucks is worth taking the risk.


I am not saying that it is worth the risk, just some people are tight budgeted and simply cant afford to go forged.


Ex. say you were in college and was having to work part time to get your car running and it was your only transportation, you would want to get it running ASAP and cheaply as possible.

[Italian LX]

A set of Keith black hyper pistons will run $250 to $300. A set off dss forged pistons run $550. I just dont see where a couple of hundered bucks is worth taking the risk.
Yeah, cause we all know that the only thing you need to buy to build a motor is the pistons, right? :rolleyes:

People that build budget motors don't just chose lesser pistons; they also chose things like cast cranks and I-beam rods. They also don't use ARP bolts and will chose other items that cost a lot less. Sure, you may only save $250 on pistons, but when you compare the whole project, you can easily shave well over $1000 off of a motor build by going with less expensive stuff.

These savings typically won't have any consequences on a motor that will be seeing only low power levels and RPMs.

[slvrbullit]

OK enough of the engineering talk in a tech thread. All post that do not pertain to this are being moved.

[Craig K.]

My first motor in the '85 had hyper pistons, this was when I was in college and working full time and was pretty much all I could afford.
The motor would have been about 300 RWHP (almost identical set up of what I have now).

I out around 30k miles on this engine, about 50 1/4 runs (fastest was a 12.5 on cheater slicks) and about 500+ miles of road racing on it (usually running between 4-6000 RPM).

The only reason I broke a piston is because I over rev'd it (no rev limitor) and dropped a valve at 7500 RPM.

I think for a budget and for a street mild strip (with no power adder) they are fine.

[QWKSNKE]

Lee, I was being sarcastic in my earlier post. We all know that hyper pistons are not as good as forged pistons. .

my bad

[Sendero]

Combustion pressure doesn't cause Hypereutectic pistons to fail; detonation and lean conditions do. On the same note, you can drive around without insurance but at some point you will most likely need it. If you are going to boost it, or give it a ton of juice then you need forged pistons.

[1Quik85GT]

It all boils down to what your future endeavors with your motor. "Racers" are always yearning for more HP!!!

[93Cobra#2771]

Wow, coming in late to this thread.

I've always heard that hyper's are more brittle than forged, which is why they tend to let loose when detonation rears it's ugly head. Is that true?

[Dale McPeters]

Wow, coming in late to this thread.

I've always heard that hyper's are more brittle than forged, which is why they tend to let loose when detonation rears it's ugly head. Is that true?

Richard,

I would not know as my car only has 2 1/2rwhp now........:jester:

[QWKSNKE]

Wow, coming in late to this thread.

I've always heard that hyper's are more brittle than forged, which is why they tend to let loose when detonation rears it's ugly head. Is that true?


I have a cracked #8 oem piston that says they are :D

[Dale McPeters]

I have a cracked #8 oem piston that says they are :D

Was Brian driving it when this happened? :jester:

[Italian LX]

Was Brian driving it when this happened? :jester:
Not sure if I was driving it when it happened... but I was driving it while the piston was cracked. :huh:

[Dale McPeters]

Not sure if I was driving it when it happened... but I was driving it while the piston was cracked. :huh:

:lol:
By the way since he has forged ones now how is the datalogging
coming along?

[Italian LX]

:lol:
By the way since he has forged ones now how is the datalogging
coming along?
Maybe if he had a forged TOB, we could datalog some more. :D

[TheJeanyus]

:rofl:

[QWKSNKE]

asses :slap:

[nxcoupe]

Hypers have a higher silicone content in them as well. KB's site has a really good article on how they are made. The higher silicone content is brought to the surface of the piston, making the pistons reflect heat back into the combustion process. This is good and bad, as that is why they are known to be brittle. The extra silicone in the aluminum makes them easier to break. Also, since they reflect so much heat, the top ring needs a really wide gap. They neglected to mention this when they first hit the market, and that is what gave them such a bad reputation. A lot of guys lifted the top ring land because the gap would close.
I always use forged pistons, don't even give it a second thought. Probe's forged pistons are so economically priced, it just doesn't make sense to go with KB's. There just isn't that much price difference.

[coupe]

Hypers have a higher silicone content...
You're thinking of breast implants...

The metal is silicon.

:smartass:

[Italian LX]

You're thinking of breast implants...
Mmmmmm. . . . implants. http://myweb.cableone.net/blombardi/homer.gif

[Dale McPeters]

Maybe if he had a forged TOB, we could datalog some more. :D

I thought he was looking for a Forged TOB a while back....:D

asses :slap:

:lol:

[LeeH]

Not all Hypereutectic pistons are the same, The KBs have a higher silicon content than most the others. If your going to build a mild N/A or keep the boost under 10psi then there is nothing wrong with Hypereutectic pistons, If your planning on lots of HP then go forged. The reason for the hypereutectic piston popularity is because with low thermal expansion characteristics it can run in a tighter bore which promotes stability and strength. The problem is that hypereutectic pistons are soo hard they are brittle and forged are more ductile, Forged pistons are more forgivable where hypereutectics will fail in a catastropic manner with little to no warning. A forged piston will fail though too, Its more of a tuning failure than overpowering the piston material.

[Dale McPeters]

Not all Hypereutectic pistons are the same, The KBs have a higher silicon content than most the others. If your going to build a mild N/A or keep the boost under 10psi then there is nothing wrong with Hypereutectic pistons, If your planning on lots of HP then go forged. The reason for the hypereutectic piston popularity is because with low thermal expansion characteristics it can run in a tighter bore which promotes stability and strength. The problem is that hypereutectic pistons are soo hard they are brittle and forged are more ductile, Forged pistons are more forgivable where hypereutectics will fail in a catastropic manner with little to no warning. A forged piston will fail though too, Its more of a tuning failure than overpowering the piston material.

Hey we need to talk about this....:jester:

[OnYx Gt]

I did not know there was even a debate possible on this subject... Hypathetic Pistons vs a Forged Pistons... Hmmmm, not really a hard descision for me at all... I dont car if I got a motor to build with 100 hp and 1 to build with 500 hp... it is gonna have a forged piston in it.... but... you can't fix stupid either... that is all I got to say.

[coupe]

:think: Well okay then. At least now though, maybe you can understand the difference in the two and maybe contribute something next time it is discussed.

[One_live95]

lmao........



jason

[joker]

.... but... you can't fix stupid either... . :lol: :lol: :lol:

[fireguy50]

Ex. say you were in college and was having to work part time to get your car running and it was your only transportation, you would want to get it running ASAP and cheaply as possible.
Why do stupid people do this?
if ya can't aford to pay, don't play so hard
:popcorn:

[OnYx Gt]

Why do stupid people do this?
if ya can't aford to pay, don't play so hard
:popcorn:
:chug: right on dude... building a motor with hypathetic pistons is like wiping your butt before you take a dump...it just does not make any sense... it is like they wany to make chicken salad out of chicken sh*t... then they are like..."it was a 100 shot... why did my piston turn to dust...?"

[coupe]

wiping your butt before you take a dump...make chicken salad out of chicken sh*t :think: Does that make any sense?

Like stated before.


I think for a budget and for a street mild strip (with no power adder) they are fine.
If your going to build a mild N/A or keep the boost under 10psi then there is nothing wrong with Hypereutectic pistons
For a budget street/strip motor, you will be fine with hypers. For something serious, that you intend on hard-use with a power-adder, go ahead & put some forged in there...Hypereutectic would do just fine for the average street-strip car.

:deadhrse:

[OnYx Gt]

:think: Does that make any sense?

Like stated before.





:deadhrse:

I am sorry, you are right, I am wrong... I am sorry for voicing my opinion, I will never do it again my lord... you have put me in my place, thank you.

[Italian LX]

... I dont car if I got a motor to build with 100 hp and 1 to build with 500 hp... it is gonna have a forged piston in it.... but... you can't fix stupid either... that is all I got to say.
Was the "fix stupid" comment refering to yourself? :think:

[OnYx Gt]

yes... like I said I am sorry boss... I should have known better to post what I thought about a hypathetic piston.. sorry

[LeeH]

I did not know there was even a debate possible on this subject... Hypathetic Pistons vs a Forged Pistons... Hmmmm, not really a hard descision for me at all... I dont car if I got a motor to build with 100 hp and 1 to build with 500 hp... it is gonna have a forged piston in it.... but... you can't fix stupid either... that is all I got to say.


I have seen a 347 and a 372 spin to 7500 on a regular basis with KB hypereutectics, Both cars run mid to low 10s here where the air sux. The 372 has not been apart since 98 or 99 and has never suffered any kind of a failure, The 347 was built in 2000 and has split 1 block but has used the same rotating assembly in both engines including the current one.(this car was sold a few months ago and is now in the San Antonio area)

I love these debates about pistons, It never fails though these same few that call hypereutectics pistons garbage are building stock block based engines. Dont get me wrong overkill is something we all particpate in but hypereutectics most often are killed by a bad tune instead of failing for no reason as presumed by some. Now if you were considering putting anything other than forged in a Dart block then thats stupid.

[Italian LX]

I have seen a 347 and a 372 spin to 7500 on a regular basis with KB hypereutectics, Both cars run mid to low 10s here where the air sux. The 372 has not been apart since 98 or 99 and has never suffered any kind of a failure, The 347 was built in 2000 and has split 1 block but has used the same rotating assembly in both engines including the current one.(this car was sold a few months ago and is now in the San Antonio area)

I love these debates about pistons, It never fails though these same few that call hypereutectics pistons garbage are building stock block based engines. Dont get me wrong overkill is something we all particpate in but hypereutectics most often are killed by a bad tune instead of failing for no reason as presumed by some. Now if you were considering putting anything other than forged in a Dart block then thats stupid.
Well said, Lee. :nice:

. . . however, the Kid already admitted that he was stupid. :D


:jester:

[One_live95]

hell i woud post up the pistons i am going with, but i am putting mine together cheap, shouldn't ever be sprayed.... and i want it to have longevity....lotsa miles....

so for the sake of getting bashed i won't say what i am going with, NOR would i LIKE to be called stupid for it.

[One_live95]

Why do stupid people do this?
if ya can't aford to pay, don't play so hard
:popcorn:


:shake:

[Italian LX]

so for the sake of getting bashed i won't say what i am going with, NOR would i LIKE to be called stupid for it.
Yeah, there's already too many other things that we call you stupid for. :poke:









. . . just kidding, Jason. :jester:

[One_live95]

LMAO.... this coming from the guy telling me to help rowdy up the peeps at MMP that time........lol


jason

[Italian LX]

LMAO.... this coming from the guy telling me to help rowdy up the peeps at MMP that time........lol


jason
:rofl: :rofl:

I forgot all about that.... now that was some funny shit. :yup:

[One_live95]

damn kids..... prolly been playing too many vidya games.....lol


jason

[nxcoupe]

You're thinking of breast implants...

The metal is silicon.

:smartass:
Damn, I am usually the one pointing out spelling errors. Jeesh. SILICON, Si on the periodic table! Not RTV!