| Author | Topic |
|---|
Location:
NSW
Registered:
July 2005
|
|
turbo piston choice
|
Tue, 06 September 2005 02:23
|
 |
I'm trying to find out what would be the best pistons to use for my up coming turbo set-up.
Whould i be better going for some Forged pistons or would it be better to go for a set of Hypereutectic pistons ?
Hypereutectic pistons are supposed to be 70% as strong as forged pistons and alot cheaper, than forged.
|
|
|
Location:
Canberra
Registered:
July 2005
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 03:47
|
|
What boost do you intend on running? If it's not high, then you won't need forgies if you are careful with your ignition and cooling. Hypereutectic just means there is more carbon in the alloy.
The advantage of not going forged will be the lack of piston knocking on a cold engine (and price), but as said above, it depends on your goals.
|
|
|
Location:
NSW
Registered:
July 2005
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 05:00
|
|
|
I want it to be able to handle high boost, but won't be running on full boost often. But i just want to get a good set of pistons that will stand up to the challenge
|
|
|
Location:
Brisbane
Registered:
May 2002
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 05:43
|
|
| tricky wrote on Tue, 06 September 2005 13:47 |
What boost do you intend on running? If it's not high, then you won't need forgies if you are careful with your ignition and cooling. Hypereutectic just means there is more carbon in the alloy.
|
Silicon actually.
| Quote: |
Hypereutectic 390 refers to a unique aluminum piston alloy that contains dissolved and free silicon. The material can be T6 heat treated to high strength and stiffness.
|
|
|
|
Location:
Parramatta
Registered:
July 2002
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 06:54
|
|
this is the way i look at it. admitidty they may be 70% as strong as a forged piston, but 1 year down the track do you really wanna be pulling the bottom end down again because you need to change a melted piston??? ask yourself that and how much money will that set you back also??? spend the money now not later.
the saying goes you get what you pay for, in this case that is very true.
|
|
|
Banned by his request
Location:
moved to tamworth
Registered:
July 2002
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 07:15
|
|
think i have answered this one a few times!the 4agze comes with forgies as standard.this gives you a clue to keeping things alive.i would never,and i mean never use cast even hypers{more silicon}pistons in a turbo rebuild.forgies give you extra insurance if something fuel wise,goes wrong.forgies are cheap as chips nowdays.the best CP customs will set you back $1100 or so,at the cheaper end you arias ones.my advice put forgies in,the extra is offset if you break the cast pistons.
mick
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 07:28
|
|
| Rob.C wrote on Tue, 06 September 2005 12:23 |
I'm trying to find out what would be the best pistons to use for my up coming turbo set-up.
Whould i be better going for some Forged pistons or would it be better to go for a set of Hypereutectic pistons ?
Hypereutectic pistons are supposed to be 70% as strong as forged pistons and alot cheaper, than forged.
|
as Norbie said, hyper-eutectic means More(hyper) silicon than the eutectic amount. hypo-eutectic means less silicon.
casting alloys have higher silicon to improve the fluidity and castability of the molten alloy.
in regards to forged or not, forged pistons basically just have work hardening in them so the metal itself is stronger by a bit, but more important is the increase in TOUGHNESS. it is this toughness that decreases the chances of breaking ringlands during detonation events which can easily occur.
as for which is stronger, i very much doubt that you will reach a point where the STRENGTH of the alloy is challenged... it is the toughness that compromises cast pistons, so if you tune it properly (ie no detonation/pre-ignition events) then a cast piston should be also quite good....
anyway.. thats the theory.. in practice you will always have some tuning fuckup and it can just take a single ping to break the righ lands....
|
|
|
Location:
Canberra
Registered:
July 2005
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 07:43
|
|
Oh, ooops... Spoke out of context there. But hypereutectic also defines certain Fe C alloys, 'cos ya find a eutectic point on just about any phase diagram for an alloy. Just depends on the constituent you define it by.
Sorry, off topic 
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 08:04
|
|
| tricky wrote on Tue, 06 September 2005 17:43 |
Oh, ooops... Spoke out of context there. But hypereutectic also defines certain Fe C alloys, 'cos ya find a eutectic point on just about any phase diagram for an alloy. Just depends on the constituent you define it by.
Sorry, off topic
|
to be entirely pedantic, for Fe-C it's often the eutectoid and not the eutectic  but i know what ya mean 
i think more car kiddies should show an interest in metallurgy dammit... too useful not to
|
|
|
Location:
NSW
Registered:
July 2005
|
|
Re: turbo piston choice
|
Tue, 06 September 2005 09:42
|
|
Yeah but where's the fun in learning all of that, when we all can come on here and ask you 
Seriously, thanks for the help. Made the choice easy 'FORGIES'
|
|
|
