Ford Focus ST Forum banner
201 - 217 of 217 Posts

· Registered
Joined
·
113 Posts
Do you have any idea if there's difference between European and USA version of pistons? I've not heard of low compression cylinders with 2013 ST even while our Euro PCM is calibrated to give constant overboost with european "regular" gasoline (about 90-91 AKI, 95RON) and run very lean in many situations. The base calibration think that it's ok to run over 1,2 bar boost @2500-4000rpm with 14.8 - 15:1 AFR for couple of seconds with AKI 93 gasoline and about 30 degC CAC temperature while flooring at highway on 6rd gear. Just does enrichment after a while and rise boost to over 1,3 bar. And does not blow pistons...
Nope, there is no difference :)

I know it because blew up cyl 4.

And AFR don't kill the pistons..... I had 11.4-11.6 AFR unter WOT when i killed it :D
The heat kills the pistons because of a very SMALL ring gap....
 

· Registered
Joined
·
19 Posts
Nope, there is no difference :)

I know it because blew up cyl 4.

And AFR don't kill the pistons..... I had 11.4-11.6 AFR unter WOT when i killed it :D
The heat kills the pistons because of a very SMALL ring gap....
Are you sure about that is the cause of failure?
Maybe the reason is not the amount of ring gap, but some of pistons are just made of a slightly too weak material? I would not excpect 100% quality control... smaller gap would be just more sensitive to material problems?

Mine has now 37000 kilometers (about 23000 miles). No program tune yet (just upgraded Ford PCM strategy CM5A-14C204-AMP). Going to do Mountune MP275 later. Around 32000 km there was more visible exhaust gases and maybe little oil blown while cold start at winter time. Still no unusual amount of oil consume or any sign of failure.

After reading all these pages of stories about piston failures I've become a little nervous. Would there be risk of failure just behind next door, that easy without even modifying but more risk with mods? Or maybe not after all...?
 

· Registered
Joined
·
531 Posts

· Registered
Joined
·
1,900 Posts

· Registered
Joined
·
178 Posts
Pablo, I just want to let everyone know the mahle pistons and molnar rods have been installed. The car runs very smooth with no issues. I'm just breaking in the new rings and I'm wondering how many miles before I can push the motor to red line?
 

· Registered
Joined
·
178 Posts
any updates?
 

· Premium Member
Joined
·
1,294 Posts
Just got caught up on this entire thread, very interesting read. Anxious to see the final results! Im close enough to NJ that if Im ever unlucky enough to have a failure I know where I will be taking my engine, you guys do impressive work!
 

· Registered
Joined
·
8 Posts

· Registered
Joined
·
122 Posts
Um.... Anything?
 
201 - 217 of 217 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top