I have an 06 Evo 9 RS and the motor let go back in February. What I can't figure out is why. Only had 123K on the motor and was my daily. It was an awesome car and I've never had any problems with it; just performed constant maintenance. I bought the car in 2010 with 6700 (not a typo) and I'm OCD when maintaining my car ie oil changes with Amsoil every 3k, all drivetrain fluids every 10k, etc. When I first got my car I did A LOT of canyon runs since I lived 5 min away and did a few track days soon after. Other than that, I drive around like grandma. Could the countless canyon runs and 4-5 track days reduce the life of the engine THAT much? It let go as I was passing someone at 60mph, I had no codes, and the engine was normal temp. Threw a rod in cylinder 2 and left a nice sized hole; just smaller than a baseball. Sorry for being longwinded, just wanted to be detailed in my post. I'd appreciate any thoughts you may have. Thanks

Mods:
TBE
intake
IC piping
Tune

 

Post a picture of broken rod and we can get a better idea of how it broke. Pictures of spark plugs would help too. And once your head is off, pictures of valves and piston. Your head should be salvageable, but won't know for certain until head is off.

 

The head was fine and passed a pressure test. I had a machine shop do a valve job and get it ready to go back on. I'll try to post pics of the plugs and other items.

 

May as well get your injectors tested and cleaned. Also, does your valve job include replacement of all your valve stems? At this time, you may want to consider S2 cams and upgraded beehive springs and titanium retainers.
What block are you going to replace with?

 

Likely spun the rod bearing, which then failed the rod. They can be silent killers sometimes. Car doesn't have the mods to make enough torque to just fail the rod.

 

Cut oil filter and look for metal bits. If you find any, oil cooler will be contaminated too and needs to be replaced since you can't really flush it. Could the turbo oil be flushed?

 

more than likely what letsgetthisdone said is correct.

 

Rod bearing failure. I had the same thing happen to me and in my case I had full bolt ons, stock turbo, stock cams. I had spun the #3 rod bearing at some point, but my motor never developed rod knock. It just blew up one day, also while I was trying to pass someone who was going too slow....which is embarrassing as hell lol.

 

what? You lost to a Prius?
Why would oem bottom end spin a rod bearing? Even Mitsubishi screws up?

 

How did you know it was a prius?! LOL. Unless....XD


After 94,000 miles of abuse, even the stock bottom end will spin a rod bearing if not carefully maintained haha. Also at the time, I was waiting the full 5000 miles between oil changes, ran E85, and made 430hp/ 414 ftlbs. I beat the **** outa that oem longblock, but boy did it perform like a dream.

 

I'm planning to have my torque detuned when I get my engine back together. You guys scare me since I'm in the same torque range on the same dyno.

 

Wait, was it really a Prius?

 

Nah, if I remember correctly it was some kind of crossover....maybe a Chrysler. Anyway i'm sure their butt holes puckered with excitement when they saw that the dumb ricer who just passed them blew up in front of them It was just me and my mobile fog machine after that.

 

A video is probably floating around YouTube. Lol
But back to thread, it is suprising that a spun bearing can occur at stock power levels. Maybe it was just worn out where there were excessive play and eventually the bottom of rod slid out enough to catch the crank corner?
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Yeah, i'm thinking the OP's rod bolts failed. Rev it high enough and the stock rod bolts will stretch, leading to a spun bearing.