forged pistons/rods on 2002

[forensicsteve]

Wanting to upgrade HP...was thinking heads/cam package...now leaning towards a Paxton or Roe. My local performance shop advises that whichever way we go, need to go to forged pistons and rods. Better handle the stress of increased HP etc.
That's adds significantly to the cost of the project.

Anybody changed to forged pistons/rods? Anybody have any negative experiences by NOT changing?

Thanks

 

[BigCarrot]

You can safely put a blower on a cast car, but you limit yourself on the amount of boost that you can safely run. The rods are strong, but I'd at least do the pistons. If you decide not to replace them, make sure you have the car tuned properly, and don't get greedy.

 

[IEATVETS]

I am having a car built for me, motor included, and I am having them install forged pistons for that very reason. They can handle a lot more boost than cast pistons. I would spend the money to have it done depending on what you want to achieve.

 

[2002_Viper_GTS_ACR]

lol.... FORGED PISTONS CAN HANDLE NOOOOOOOOOO MORE BOOST THEN HYPERUTETIC... Jesus.. will you guys ever learn..


Forged pistons handle DETONATION a lot better, they dont crack as easily. IF you have no detonation, a hyperutetic (what you girls are calling cast) piston will handle just as much pressure as a forged.

Lesson over.

Jon

 

[RedGTS]

lol.... FORGED PISTONS CAN HANDLE NOOOOOOOOOO MORE BOOST THEN HYPERUTETIC... Jesus.. will you guys ever learn..


Forged pistons handle DETONATION a lot better, they dont crack as easily. IF you have no detonation, a hyperutetic (what you girls are calling cast) piston will handle just as much pressure as a forged.

Lesson over.

Jon

Dear school ma'rm: Anyone but a girl would know that Viper cast pistons are eutectic, not hypereutectic. For that matter anyone but a girl probably could spell hypereutectic.

P.S. While your statement about boost and cast pistons might have some truth in theory, in practice it is largely false because as a practical matter, as boost rises, so do the odds of detonation.

 

[IEATVETS]

You better tell that to all of these engine builders then. Because EVERY engine builder I have ever talked to says forged are better. They can handle the increased cylinder pressure far better than cast. You should also contact all of these Viper owners that have a Roe blower and have cast pistons and let them know that yes indeedy, you can run a bigger pulley and not worry about a thing, contrary to what they have been told for all of these years.

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[1TONY1]

Wanting to upgrade HP...was thinking heads/cam package...now leaning towards a Paxton or Roe. My local performance shop advises that whichever way we go, need to go to forged pistons and rods. Better handle the stress of increased HP etc.
That's adds significantly to the cost of the project.

Anybody changed to forged pistons/rods? Anybody have any negative experiences by NOT changing?

Thanks

The rods you have are pretty darn stout. They even have ARP rod bolts from the factory. Many 700/800+ rwhp Vipers with stock rods.

 

[RedGTS]

The rods you have are pretty darn stout. They even have ARP rod bolts from the factory. Many 700/800+ rwhp Vipers with stock rods.

Or more.

 

[1TONY1]

That is why I said


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[Camfab]

As far as I've understood it 2000+ pistons are in fact hypereutectic. The Mopar Performance parts catalog has the factory .1mm oversize pistons and clearly states that they are in fact hypereutectic. 75 grams lighter than 92-99 pistons as well as a tighter higher ring package. The higher ring package makes these pistons more susceptible to damage from detonation. Less mass = higher / quicker rev potential for a unblown engine. Actually for a blown engine as well, but at the expense of reliability.

 

[RedGTS]

As far as I've understood it 2000+ pistons are in fact hypereutectic. The Mopar Performance parts catalog has the factory .1mm oversize pistons and clearly states that they are in fact hypereutectic. 75 grams lighter than 92-99 pistons as well as a tighter higher ring package. The higher ring package makes these pistons more susceptible to damage from detonation. Less mass = higher / quicker rev potential for a unblown engine. Actually for a blown engine as well, but at the expense of reliability.

Don't know what's in the Mopar catalogue but when Sean Roe was developing his supercharger system he consulted with an engineer at Mahle, which manufactures the pistons in question, and the guy told Sean the pistons are in fact eutectic, not the stronger hypereutectic.

 

[2002_Viper_GTS_ACR]

You better tell that to all of these engine builders then. Because EVERY engine builder I have ever talked to says forged are better. They can handle the increased cylinder pressure far better than cast. You should also contact all of these Viper owners that have a Roe blower and have cast pistons and let them know that yes indeedy, you can run a bigger pulley and not worry about a thing, contrary to what they have been told for all of these years.

You must be registered for see images attach

Ok, now I need you to take a reading comprehension class (as I do a spelling class), no where did I say it was SAFER or just AS SAFE to run hypercrap over forged. But ideally both pistons can handle the same amount of pressure, what they cant handle is the same amount of detonation. This is JUST like forged and cast crank shafts. Believe it or not a cast crank shaft is stronger then a forged one, however, once you reach that "breaking point" on cast, it actually cracks, where as forged will just flex/bend slightly. Therefore you can make no more power with a forged crank over a cast crank, just a margin of safety. Pistons being equal are the same thing, same ring land package, etc will yield comperable power and work load, but detonation would be the discerning factor.

Now all you girls who are talking from NO experience in building motors, please ****, if you have actually ever put your hands on some pistons and installed them in a block.. maybe its worth listening to you. Probably not, becasue all you guys do is regugitate what you have heard from others, instead of investigating it yourself.

Piss off.

Love Jon

 

[ERDOC]

You better tell that to all of these engine builders then. Because EVERY engine builder I have ever talked to says forged are better. They can handle the increased cylinder pressure far better than cast. You should also contact all of these Viper owners that have a Roe blower and have cast pistons and let them know that yes indeedy, you can run a bigger pulley and not worry about a thing, contrary to what they have been told for all of these years.

You must be registered for see images attach

Ok, now I need you to take a reading comprehension class (as I do a spelling class), no where did I say it was SAFER or just AS SAFE to run hypercrap over forged. But ideally both pistons can handle the same amount of pressure, what they cant handle is the same amount of detonation. This is JUST like forged and cast crank shafts. Believe it or not a cast crank shaft is stronger then a forged one, however, once you reach that "breaking point" on cast, it actually cracks, where as forged will just flex/bend slightly. Therefore you can make no more power with a forged crank over a cast crank, just a margin of safety. Pistons being equal are the same thing, same ring land package, etc will yield comperable power and work load, but detonation would be the discerning factor.

Now all you girls who are talking from NO experience in building motors, please ****, if you have actually ever put your hands on some pistons and installed them in a block.. maybe its worth listening to you. Probably not, becasue all you guys do is regugitate what you have heard from others, instead of investigating it yourself.

Piss off.

Love Jon

A little too much caffeine this morning?

 

[GTS-R 001]

Call Todd at Arrow, new pistons and or rods are a week away if you so desire. Outside of the materials the 2000+ pistons are made of the design is also the limiting factor, the top edge of the stock 2000+ piston is thin and can break off and destroy your engine if subjected to detonation, the diamond pistons that Arrow will sell you are forged and also have mucho improved ring ( whatever you call its, ie I am not a piston head but have already been there and done that on this one, call Todd and he will telll you all about it. )

 

[IEATVETS]

Naw, forget it Steve. Jon is right and every thing that all of us have ever heard about pistons is wrong, including Sean Roe. So all of you guys with a blower and nitrous that have cast pistons, turn up juice a little more, or a lot for that matter, Jon says it is OK.

You must be registered for see images attach

 

[2002_Viper_GTS_ACR]

Naw, forget it Steve. Jon is right and every thing that all of us have ever heard about pistons is wrong, including Sean Roe. So all of you guys with a blower and nitrous that have cast pistons, turn up juice a little more, or a lot for that matter, Jon says it is OK.

You must be registered for see images attach

Wow, do you need me to read my post back to you? Maybe you have been eating too much crack and not enough vettes.

And steve is far more correct then you were, becasue he had a rational thought/logic behind it, if the ring lands are higher up, and thinner they will have the potential to crack more, regardless of wether they are forged or hypercrap. Also, since you like to just read stuff and not research, maybe you can read that the higher ring packages are actually more efficient in the combustion process, so just because they are higher, doesnt make them bad.

 

[Ulysses]

Don't know what's in the Mopar catalogue but when Sean Roe was developing his supercharger system he consulted with an engineer at Mahle, which manufactures the pistons in question, and the guy told Sean the pistons are in fact eutectic, not the stronger hypereutectic.

I'ld probably talk to that engineer again, or some other engineer at Mahle, since conventional cast pistions ("eutectic") were used on early model cars. Car manufacturers who use cast pistons on late model cars use hypereutectic pistons. Plus it would make no sense to go from a forged piston to a eutectic piston which has inferior properties (beyond weight and tighter dimensions) than forged.

 

[2002_Viper_GTS_ACR]

Don't know what's in the Mopar catalogue but when Sean Roe was developing his supercharger system he consulted with an engineer at Mahle, which manufactures the pistons in question, and the guy told Sean the pistons are in fact eutectic, not the stronger hypereutectic.

I'ld probably talk to that engineer again, or some other engineer at Mahle, since conventional cast pistions ("eutectic") were used on early model cars. Car manufacturers who use cast pistons on late model cars use hypereutectic pistons. Plus it would make no sense to go from a forged piston to a eutectic piston which has inferior properties (beyond weight and tighter dimensions) than forged.

You are correct, RedGTS is wrong or he has his facts wrong. Dodge only moved to hypercrap, because they wanted to reduce emissions, which was best accomplished by running tighter tolerances on the piston to wall clearances, which the hypercrap allow you to do, due to their lower thermal expansion rate. Forged pistons expand more when they are hot, so they have to be put in "looser" bores, to accomodate that expansion, which gives worse emissions when cold.

Jon

 

[RedGTS]

Found the post with Sean's comment in it:

http://vca2.viperclub.org/forums/showflat.php?Cat=&Board=UBB14&Number=284316&Forum=UBB14&Words=eutectic&Match=Entire%20Phrase&Searchpage=0&Limit=25&Old=allposts&Main=283972&Search=true#Post284316

And I'm willing to bet Sean didn't get his facts wrong. Now as for whether the Mahle guy knows what he's talking about, that would seem an awfully elementary mistake for an engineer who works for a piston manufacturer, but hey, he may not be as smart as someone who thinks boost and detonation aren't related to each other.

 

[BigCarrot]

Now all you girls who are talking from NO experience in building motors, please ****, if you have actually ever put your hands on some pistons and installed them in a block.. maybe its worth listening to you. Probably not, becasue all you guys do is regugitate what you have heard from others, instead of investigating it yourself.

Piss off.

Love Jon

This was where my cast piston motor was before I ruined NINE pistons.

This is me working away on it. I'll keep talking....

 

[RedGTS]

Re: forged pistons/rods on 2002

BC, I could have used you last year.

Ulysses, I don't know what the current split is between eutectic and hypereutectic, but unless the factory's specs are wrong several new engines use eutectic rather than hyper, including the 5.7L Hemi and the LS7 in the new Z06. Not to mention this quote from a two year old article on piston design:

"Machining hypereutectic pistons is also more difficult because of the harder alloy. Consequently, hypereutectic pistons typically cost several dollars more than standard alloy pistons. That’s why most OEMs (except Ford) have gone back to eutectic alloy pistons in their late model engines. High copper eutectic alloys offer most of the advantages of hypereutectic alloys without as much cost."

 

[2002_Viper_GTS_ACR]

Re: forged pistons/rods on 2002

Big Carrot... he's my hero... yeah.. yeah...

Ok, not really...


But at least he has experience in actually doing something with them, not just talking about it.



So Red, let me get this straight: "boost and detonation aren't related to each other"

So in order to have boost, I have to have detonation? Yeah, go back to reading.. Or.. let me get this, in order to have detonation, I must have boost (forced induction)?

Yeah, please let Sean go back to talking, he is obviously the educated one amongst the two of you.

Jon

 

[Ulysses]

Re: forged pistons/rods on 2002

Consequently, hypereutectic pistons typically cost several dollars more than standard alloy pistons. That’s why most OEMs (except Ford) have gone back to eutectic alloy pistons in their late model engines. High copper eutectic alloys offer most of the advantages of hypereutectic alloys without as much cost."

This could be true since alloys are improved all the time and the adaption of new technology is very rapid. It also voids this statement in bold:

when Sean Roe was developing his supercharger system he consulted with an engineer at Mahle, which manufactures the pistons in question, and the guy told Sean the pistons are in fact eutectic, not the stronger hypereutectic.

 

[RedGTS]

Re: forged pistons/rods on 2002

Consequently, hypereutectic pistons typically cost several dollars more than standard alloy pistons. That’s why most OEMs (except Ford) have gone back to eutectic alloy pistons in their late model engines. High copper eutectic alloys offer most of the advantages of hypereutectic alloys without as much cost."

This could be true since alloys are improved all the time and the adaption of new technology is very rapid. It also voids this statement in bold:

when Sean Roe was developing his supercharger system he consulted with an engineer at Mahle, which manufactures the pistons in question, and the guy told Sean the pistons are in fact eutectic, not the stronger hypereutectic.

Neither statement is mine so I don't really care one way or the other, but how so? The first statement doesn't say eutectic is as strong as hyper, it just says the copper alloys offer "most of the advantages" of hyper. Admittedly overall "strength" is somewhat meaningless without additional context, but I don't read it as saying they're just as strong. And of course the Mahle guy may just have been stating his opinion anyway, and others may disagree.

 

[RedGTS]

Re: forged pistons/rods on 2002

So Red, let me get this straight: "boost and detonation aren't related to each other"

So in order to have boost, I have to have detonation? Yeah, go back to reading.. Or.. let me get this, in order to have detonation, I must have boost (forced induction)?

Yeah, please let Sean go back to talking, he is obviously the educated one amongst the two of you.

Jon

Jon, you can't possibly be dumb enough not to understand what I've been saying, but just in case. . . . Of course you don't have to have detonation to have boost, nor do you have to have FI to have detonation. I didn't say detonation was always present with boost, or vice versa--I said they are RELATED (in a way very important to this discussion). Your original misguided effort to paint yourself as smarter than the "class" was to insist that detonation was what killed cast pistons, not boost. My original response was to note that, while that may be literally largely true, as a practical matter it is meaningless. In other words, you were trying to be a smart ass based purely on semantics. Why? Because as boost goes up so does the LIKELIHOOD of detonation, for reasons I'm sure you're well aware of (increased heat being the place to start). Is it POSSIBLE to avoid detonation as you continue to increase boost? Sure, up to a point. You can cool the air charge, use higher octane fuel, etc. But the more boost rises the more difficult it gets. That is why Sean won't advise anyone to run more than 5 psi of BOOST on a cast piston car, or 6.5 psi with his water/**** setup. I don't think he or anyone else would say it's impossible to run more boost with cast pistons without a failure; the point is it's not worth the risk of detonation over a certain level. There may be people reading this (although God knows I don't know why at this point) who are using the information to make signficant decisions about FI and whether to replace their pistons, and you aren't doing them any favors by putting form over substance.

BTW, since you're so interested, I pulled my tranny yesterday, but I don't have any pictures of me in the act (come to think of it, BC could have just been posing in that picture).

 

[Ulysses]

Re: forged pistons/rods on 2002

Consequently, hypereutectic pistons typically cost several dollars more than standard alloy pistons. That’s why most OEMs (except Ford) have gone back to eutectic alloy pistons in their late model engines. High copper eutectic alloys offer most of the advantages of hypereutectic alloys without as much cost."

This could be true since alloys are improved all the time and the adaption of new technology is very rapid. It also voids this statement in bold:

when Sean Roe was developing his supercharger system he consulted with an engineer at Mahle, which manufactures the pistons in question, and the guy told Sean the pistons are in fact eutectic, not the stronger hypereutectic.

Neither statement is mine so I don't really care one way or the other, but how so? The first statement doesn't say eutectic is as strong as hyper, it just says the copper alloys offer "most of the advantages" of hyper. Admittedly overall "strength" is somewhat meaningless without additional context, but I don't read it as saying they're just as strong. And of course the Mahle guy may just have been stating his opinion anyway, and others may disagree.

Well.. I read that as strength and less thermal expansion, since those are the two properties that auto makers are always talking about striving for when you read one of these piston alloy articles. The other advantage of silicon in an alloy is lubricity, which is something that copper would not add to the alloy properties.

 

[2002_Viper_GTS_ACR]

Re: forged pistons/rods on 2002

So Red, let me get this straight: "boost and detonation aren't related to each other"

So in order to have boost, I have to have detonation? Yeah, go back to reading.. Or.. let me get this, in order to have detonation, I must have boost (forced induction)?

Yeah, please let Sean go back to talking, he is obviously the educated one amongst the two of you.

Jon

Jon, you can't possibly be dumb enough not to understand what I've been saying, but just in case. . . . Of course you don't have to have detonation to have boost, nor do you have to have FI to have detonation. I didn't say detonation was always present with boost, or vice versa--I said they are RELATED (in a way very important to this discussion). Your original misguided effort to paint yourself as smarter than the "class" was to insist that detonation was what killed cast pistons, not boost. My original response was to note that, while that may be literally largely true, as a practical matter it is meaningless. In other words, you were trying to be a smart ass based purely on semantics. Why? Because as boost goes up so does the LIKELIHOOD of detonation, for reasons I'm sure you're well aware of (increased heat being the place to start). Is it POSSIBLE to avoid detonation as you continue to increase boost? Sure, up to a point. You can cool the air charge, use higher octane fuel, etc. But the more boost rises the more difficult it gets. That is why Sean won't advise anyone to run more than 5 psi of BOOST on a cast piston car, or 6.5 psi with his water/**** setup. I don't think he or anyone else would say it's impossible to run more boost with cast pistons without a failure; the point is it's not worth the risk of detonation over a certain level. There may be people reading this (although God knows I don't know why at this point) who are using the information to make signficant decisions about FI and whether to replace their pistons, and you aren't doing them any favors by putting form over substance.

BTW, since you're so interested, I pulled my tranny yesterday, but I don't have any pictures of me in the act (come to think of it, BC could have just been posing in that picture).

God, please don't tell me you actually re-read that when you were done and thought "oh this is going to show him just how smart I am." That was such dribble, which can be gotten off the introductory page of "Supercharged!" ( http://www.bentleypublishers.com/product.htm?code=gsup ) Of course, only AFTER you had to recant your prior BS about boost and detonation being related. Just to make sure we are using the same English language, this is the same "related" you speak of: http://dictionary.reference.com/search?q=related "Being connected; associated. " I don't believe they are connected, or associated, and can completely occur independent of each other, which you admitted after I corrected you.

Thanks for playing, at least its mildly amusing.

So the value in all of this is the link above, if you are serious about understanding supercharging, it would do you well to at least buy and read "SuperCharged!"

Jon

 

[RedGTS]

Re: forged pistons/rods on 2002

Dearest Jon, I'm quite content to leave the record as it is, as I am confident the literate among us can make up their own mind as to who is doing the squirming here (claiming that increases in boost are not "associated" with detonation because the two conditions can occur independently of each other displays a rather rudimentary grasp of language and logic, as smoking cigarettes and lung cancer can occur independently of each other as well, yet no one but a fool would claim they aren't associated with each other--neither associated nor related means "you never see one without the other").

P.S.--the word you're looking for is "drivel," not dribble.

 

[2002_Viper_GTS_ACR]

Re: forged pistons/rods on 2002

Dearest Jon, I'm quite content to leave the record as it is, as I am confident the literate among us can make up their own mind as to who is doing the squirming here (claiming that increases in boost are not "associated" with detonation because the two conditions can occur independently of each other displays a rather rudimentary grasp of language and logic, as smoking cigarettes and lung cancer can occur independently of each other as well, yet no one but a fool would claim they aren't associated with each other--neither associated nor related means "you never see one without the other").

P.S.--the word you're looking for is "drivel," not dribble.

Dearest Ronnie,

Thank you for the kind words. I too will stick to the record being as it is. I was right, and you corrected yourself. Thanks for playing.

Jon