So lets challenge some you guys knowledge and see who can figure out what caused this to happen.
I broke the so called proven 1k hp crower rod last night driving normal. I purchased these brand new in January.

1. piston and rings in perfect condition
2. all cylinders perfect condition
3. bearings and journals look perfect
4. no frozen wrist pin, no frozen crank, rod cap or piston

 

You might want to send ALL of your rods back to crower. You may have gotten a defective one. Were the rods weighed before install? If so, what were the weights of each?

 

pretty sure everything was balanced & shit to spec...


Sucks Richard hopefully they Give you some money back or a new set of rods...even though theres a whole in your block now.

 

Shitty situation. How many miles have you put on them since install? Who did the work on the motor?

 

I do all the work and assembly it has just over 8k miles on the entire engine. The rods were all weighed to exact weight from crower they came with a spec sheet but I dont have it anymore tho. all the rods go in a certain 1-4 order and they were all correct cause it says #4 right on the rod and it was #4 cylinder. I also had the entire rotating assemble balanced by the machine shop before my assembly. The motor was making just over 600 ish maybe closer to 650 if i had to guess but maybe only 550. only theory that was thrown out is too much cylinder pressure but if that was the case wouldnt the head lift first or break the stock size wrist pin before the rod?

 

Wow

 

It looks like the rod bent and then fractured. Was the car detonating at all?

 

This is exactly what I was trying to warn you about when you were on your campaign on how much more timing you were able to add on E100 injection over methanol. Looks like the rod bent then snapped. Classic case of too much cylinder pressure. Let's face facts here, this is the second motor that you built in the 6 months that has blown in the exact same manner with two completely different rods from two completely different companies. Do you honestly think you just have such bad luck that you got two batches of defective rods that are completely unrelated? Let's be realistic here....

 

did you have any misfires during tuning? I experienced two bent rods last year. In my case I believe misfires are the culprit. wasted spark ignition is designed to fire the unburned fuel left over from combustion. in case of misfire there would be tons of leftover fuel. my theory is ethanol burns slow enough that there is still a burn happening when the fresh air/fuel charge comes in. this leads to a serious burn when piston is on its way up bore. perfect scenario to bend a rod.

the theory rods bend from passing MBT doesnt work for me. preignition makes far more sense. I shared my theories in this thread. while not generally accepted it may offer insite for you.
http://forums.evolutionm.net/alterna...-bad-news.html

I dont know if I ever shared my timing. it was approximately 3 at peak torque raising to 14. when there were no misfires it ran for months. after misfires it ran for days befor rods bent.

 

Tune was a fail...........what do your logs look like when you were running