Welcome to the North American Subaru Impreza Owners Club Friday March 29, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Built Motor Discussion

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 02-26-2009, 08:58 PM   #1
CHEWY911
Scooby Newbie
 
Member#: 179450
Join Date: May 2008
Location: Minnesota
Vehicle:
2004 WRX
Silver

Default Mahle Stroker Piston?

Has anyone used the Mahle stroker pistons in an EJ205 with the STi crank? I was going to to go this route and see if anyone had any opinions or experience with these. The only hesitation I had was that these were 4032 alloy. At my powere levels probably not a big deal, just wanted a little safety margin for any unexpected detonation.
* Registered users of the site do not see these ads.
CHEWY911 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 02-27-2009, 06:19 AM   #2
And70
Scooby Newbie
 
Member#: 171055
Join Date: Feb 2008
Location: Sydney Australia
Vehicle:
2001 STI Wagon
2nd Top Scoob #22

Default

I'm also about to head down this path with 2.0l closed deck block and 2.5 sti crank and I'm interested in any reports on the Mahle's as well.
And70 is offline   Reply With Quote
Old 02-27-2009, 07:34 AM   #3
seanathanq83
Scooby Guru
 
Member#: 173241
Join Date: Feb 2008
Chapter/Region: TXIC
Location: Houston, Tx
Vehicle:
2002 s256 twinscroll
now with one more gear

Default

they make that piston in both alloys, i have talked to them. the actually gave me both part numbers just dont know where it is
seanathanq83 is offline   Reply With Quote
Old 02-28-2009, 12:40 AM   #4
CHEWY911
Scooby Newbie
 
Member#: 179450
Join Date: May 2008
Location: Minnesota
Vehicle:
2004 WRX
Silver

Default

Quote:
Originally Posted by seanathanq83 View Post
they make that piston in both alloys, i have talked to them. the actually gave me both part numbers just dont know where it is
Great, thanks for the info! Are there any other manufacturers that make these pistons off the shelf?
CHEWY911 is offline   Reply With Quote
Old 02-28-2009, 12:47 AM   #5
reddevil
Scooby Guru
 
Member#: 64673
Join Date: Jun 2004
Chapter/Region: NWIC
Location: portland
Vehicle:
1990 Legacy wagon
goes 12.387 @ 116.5

Default

I built a stroked speC ej20 with these pistons. I never heard back from the buyer, so all I know is that it must have worked. Everything went together as it should have. I took the pistons and block to my mahine shop and had the block bored to fit the pistons.
reddevil is offline   Reply With Quote
Old 02-28-2009, 12:50 AM   #6
reddevil
Scooby Guru
 
Member#: 64673
Join Date: Jun 2004
Chapter/Region: NWIC
Location: portland
Vehicle:
1990 Legacy wagon
goes 12.387 @ 116.5

Default

The EASIEST way to tell if you have the correct pistons is to get a used STI 2.5 piston. Then lay the STI piston on its face and lay the stroker piston on its face next to the STI piston. Simply visually compare the pistons. The wrist pin locations should be spot on comparable. Unless you have serious vision problems you will be able to detect the 2mm difference between wrist pin location (stock 75mm pistons are 2mm higher than 79mm pistons).
reddevil is offline   Reply With Quote
Old 02-28-2009, 01:18 AM   #7
CHEWY911
Scooby Newbie
 
Member#: 179450
Join Date: May 2008
Location: Minnesota
Vehicle:
2004 WRX
Silver

Default

Quote:
Originally Posted by reddevil View Post
The EASIEST way to tell if you have the correct pistons is to get a used STI 2.5 piston. Then lay the STI piston on its face and lay the stroker piston on its face next to the STI piston. Simply visually compare the pistons. The wrist pin locations should be spot on comparable. Unless you have serious vision problems you will be able to detect the 2mm difference between wrist pin location (stock 75mm pistons are 2mm higher than 79mm pistons).
Is it worth going with this set up over a 2.0 with a standard crank? Because I'd prefer to go with Manley or Ross pistons, but they don't make any for a stroker.
CHEWY911 is offline   Reply With Quote
Old 03-26-2009, 10:43 AM   #8
UA_WRX
Scooby Newbie
 
Member#: 88986
Join Date: Jun 2005
Location: Carrollton, Ga
Vehicle:
2002 WRX
Aspen White

Default

I've got the motor reddevil is built with the mahles and they seem to be working really well. A little bit of noise and smoke at startup in real cold weather but other than that very quiet for a forged piston. Motor is running good and soon to be tuned.
UA_WRX is offline   Reply With Quote
Old 03-26-2009, 11:43 AM   #9
reddevil
Scooby Guru
 
Member#: 64673
Join Date: Jun 2004
Chapter/Region: NWIC
Location: portland
Vehicle:
1990 Legacy wagon
goes 12.387 @ 116.5

Default

Great to hear that!
reddevil is offline   Reply With Quote
Old 03-27-2009, 03:44 AM   #10
ejpowerguy
*** Banned ***
 
Member#: 175944
Join Date: Mar 2008
Chapter/Region: MWSOC
Location: NASC Garage
Default

I am also thinking of going this route. I am interested to get details from any users of this combo.
ejpowerguy is offline   Reply With Quote
Old 03-27-2009, 03:48 AM   #11
reddevil
Scooby Guru
 
Member#: 64673
Join Date: Jun 2004
Chapter/Region: NWIC
Location: portland
Vehicle:
1990 Legacy wagon
goes 12.387 @ 116.5

Default

Assembly wise, its as easy as pie.

Take block and pistons to machine shop. Have block bored to fit pistons.

Assemble.

Drive.


Really that simple. You are just swapping the crank and rods, the machine shop does teh "hard part" of boring. Make sure the bearings are good to go, and thats it.
reddevil is offline   Reply With Quote
Old 03-27-2009, 01:00 PM   #12
Ostrowrx
Scooby Specialist
 
Member#: 141342
Join Date: Feb 2007
Chapter/Region: NESIC
Location: Hamden CT
Vehicle:
2010 WRX STI
Black

Default

Quote:
Originally Posted by seanathanq83 View Post
they make that piston in both alloys, i have talked to them. the actually gave me both part numbers just dont know where it is

sub193642I16, just got off the phone with them.
Ostrowrx is offline   Reply With Quote
Old 09-14-2009, 06:15 PM   #13
soobaviator
Scooby Specialist
 
Member#: 115070
Join Date: May 2006
Chapter/Region: MAIC
Location: Northern VA
Vehicle:
2009 DGM LGT Spec.B
08 Audi Q7 4.2 PRM

Default

Im using these pistons in my build as well...

soobaviator is offline   Reply With Quote
Old 01-27-2010, 06:38 PM   #14
DSM Nexus
Scooby Specialist
 
Member#: 196985
Join Date: Dec 2008
Chapter/Region: TXIC
Vehicle:
2004 EVO VIII
Black

Default

Where is a good place to get the mahle ots pistons and how much are you guys spending. Also do they come with the rings/pins/clips and so on?
DSM Nexus is offline   Reply With Quote
Old 01-27-2010, 07:28 PM   #15
RealStreet
Former Vendor
 
Member#: 205916
Join Date: Mar 2009
Chapter/Region: South East
Location: I SELL ENGINE PARTS!
Vehicle:
2003 Subaru WRX
in the 10's and the bends

Default

We can do Mahle ots pistons for $555 shipped.

Give me a call and let me know.

www.RealStreetPerformance.com
407-695-0699
RealStreet is offline   Reply With Quote
Old 01-28-2010, 07:54 AM   #16
Zackbo
Scooby Specialist
 
Member#: 43151
Join Date: Sep 2003
Chapter/Region: South East
Location: Charlotte, NC
Vehicle:
04 STI
Kinda Silver-ish

Default

You can also use the stock pistons and really thick (2mm) head gaskets, FYI.
Zackbo is offline   Reply With Quote
Old 01-28-2010, 10:43 AM   #17
DSM Nexus
Scooby Specialist
 
Member#: 196985
Join Date: Dec 2008
Chapter/Region: TXIC
Vehicle:
2004 EVO VIII
Black

Default

Quote:
Originally Posted by Zackbo View Post
You can also use the stock pistons and really thick (2mm) head gaskets, FYI.
Isnt stroke how far the piston moves up? If so then if its going from a 75mm to a 79mm stroke, wouldnt you in fact need a 4mm one without any decking to the block/heads.
DSM Nexus is offline   Reply With Quote
Old 01-28-2010, 11:46 AM   #18
reddevil
Scooby Guru
 
Member#: 64673
Join Date: Jun 2004
Chapter/Region: NWIC
Location: portland
Vehicle:
1990 Legacy wagon
goes 12.387 @ 116.5

Default

No, the stroke goes IN 2mm, and OUT 2mm, adding to 4mm overall.
reddevil is offline   Reply With Quote
Old 01-28-2010, 12:06 PM   #19
DSM Nexus
Scooby Specialist
 
Member#: 196985
Join Date: Dec 2008
Chapter/Region: TXIC
Vehicle:
2004 EVO VIII
Black

Default

Quote:
Originally Posted by reddevil View Post
No, the stroke goes IN 2mm, and OUT 2mm, adding to 4mm overall.
Ah ok, thanks for the clarification on that.
DSM Nexus is offline   Reply With Quote
Old 01-05-2011, 05:25 PM   #20
Club_Sport
Scooby Newbie
 
Member#: 254845
Join Date: Aug 2010
Chapter/Region: MAIC
Default

What kind of clearance are people running with these? I was recommended .0025-.0033 but that is a little too much for me. These are the 4032 alloy and this is going to be 300-350hp maximum.
Club_Sport is offline   Reply With Quote
Old 01-05-2011, 08:45 PM   #21
soobaviator
Scooby Specialist
 
Member#: 115070
Join Date: May 2006
Chapter/Region: MAIC
Location: Northern VA
Vehicle:
2009 DGM LGT Spec.B
08 Audi Q7 4.2 PRM

Default

mine are at .0024; quiet on start up and oil consumption is about a cup every 2k with Syntec 30wt/40wt blend and hard driving. Cars at ~300WHP now plan is 350-400WHP...

Mahle now makes these in a Power Pak Plus out of 2618 alloy (P/N SUB193642P16). Price is $506.42 shipped from autopartsdealer.com. That's an amazingfreakin price!
soobaviator is offline   Reply With Quote
Old 01-05-2011, 08:47 PM   #22
KpT KiM
Scooby Specialist
 
Member#: 242422
Join Date: Mar 2010
Default

I wish they made these with a higher compression ratio.
KpT KiM is offline   Reply With Quote
Old 01-16-2011, 10:11 PM   #23
soobaviator
Scooby Specialist
 
Member#: 115070
Join Date: May 2006
Chapter/Region: MAIC
Location: Northern VA
Vehicle:
2009 DGM LGT Spec.B
08 Audi Q7 4.2 PRM

Default

Mahle can do custom pistons for you. You have to call them. Base price is around $650 for custom EJ Power Pak pistons.
soobaviator is offline   Reply With Quote
Old 01-17-2011, 05:59 AM   #24
WReXd
Scooby Specialist
 
Member#: 114101
Join Date: May 2006
Chapter/Region: SCIC
Location: Buena Park, CA
Vehicle:
93 Impreza L Swap

Default

I was quoted much higher than that for custom Mahles (~$1k... no idea why). Ended up going with CP instead for $550 shipped. I did exactly what you're asking, kim. Stroker 4032 pistons with 9.5:1 CR. What's interesting is that the recommended p/w clearance on those were 0.0015"...
WReXd is offline   Reply With Quote
Old 01-17-2011, 10:25 AM   #25
MartinSTi05
Scooby Specialist
 
Member#: 145145
Join Date: Apr 2007
Chapter/Region: MWSOC
Location: Rockford, Il
Vehicle:
2006 wrx STi

Default

Quote:
Originally Posted by WReXd View Post
I was quoted much higher than that for custom Mahles (~$1k... no idea why). Ended up going with CP instead for $550 shipped. I did exactly what you're asking, kim. Stroker 4032 pistons with 9.5:1 CR. What's interesting is that the recommended p/w clearance on those were 0.0015"...
I'm thinking the tight PTW clearance has to do with the 4032 alloy.
MartinSTi05 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
EJ20 wrx block, mahle forged pistons, stock exh manifold 69subaru360 Engine/Power/Exhaust 21 10-30-2008 08:23 PM
EJ20 block, mahle forged pistons. 69subaru360 Tri-State Area Private Classifieds 12 10-29-2008 02:51 PM
New STi short block + Mahle Coated Pistons + Manley Rods = Good to max out the 35R? boostinscooby Built Motor Discussion 9 12-19-2006 03:49 AM
FS Mahle Forged Pistons 99.5 kurion Engine/Power/Exhaust 2 12-14-2006 11:25 AM
Anyone use Mahle Powerpack Pistons?? BigJ04STi Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) 19 06-03-2005 11:28 PM

All times are GMT -4. The time now is 07:25 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.