Edkiefer
Well-Known Member
I think its going to be hard to tell , under a controlled tests, yes you could tell but for us I feel its tough call because of how these piston explode.I started a thread here
http://www.mustang6g.com/forums/showthread.php?t=49520
Lets get a database set up.
I'd like to know if it was the Piston or the rod that let go.
I'm guessing it's mostly the pistons letting go first allowing the small end of the rod to go wild. Cast hypereutectic pistons are extremely sensitive to knock and any small manufacturing defect will cause them to be even more brittle.
Rods snapping is on stock motors seems more a function of LSPI (aka as Super Knock).
Since it seems it is always Cyl 2 and Cyl 3 letting go it supports the theory that this is an oil related issue as on most ecoboost engines those are the ones with the most oil coating due to pcv.
I'm not an engineer, I started studying engineering but switched to IT after a year so I do know more than the average person and alot of theory, but real world experience is lacking. For that I am in contact with my old professor who was an engineer at Opel (GM I know but I don't hold it against him.)
He has given me a few charts that are enlightening as related to Early Ecotec failures.
I'll put them in the other thread and would like the tuners who have loads of real world experience to chime in.
Was it the rod bending a bit causing side thrust on piston, was it the piston itself first .
I don't know for sure, but there are things that raise % of maybe problems. Most are already been posted but just thinking out loud here a few things.
1) as posted before piston material is very important with turbo engines lasting .
2) the low tension piston rings many manufacturers are using can have higher blow-by under load conditions.
3) With bad blow-by and having IC low mounted, there might be a issue of oil building up in IC, then under high rpm/loads it goes into intake at higher % rate and raises knock possibility .On this note to, if true better IC would hurt this more as blow-by gases cool more and separate oil.
4)Might be cooling problem in the block/head making some cylinders more prone to knock.
5)Timing issues with clamping force only for cam, crank sensors could affect ignition and cam timings.
My guess is these motors are being pushed right from factory so anything that not right or any combination can add up quick to a failure, but that is a guess.
I would definitely add CC on these engines even if not moded.
Be interesting to see what focus RS has changed on engine, parts wise.
Sponsored
Last edited: