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iceminion
05-21-2008, 02:14 PM
Ok, last night I spun a rod bearing.

This was Bills engine, he works at MAP, he does not build engines for customers, I in no way believe that his craftsmanship was in any way responsible for the failure. 2.3L eagle/mahle (9.5:1) ~500 miles on engine.

I am 1/2 qt overfilled with oil, been that way for a couple weeks. I have no oil leaks.

Did a high revving launch (first time on this engine)

The engine makes a terrible noise, and there are small golden flakes in the oil.

The car is running on keydiver chip (for the 780cc's)

I have been running the car at 11-12psi because of the high compression ratio.

Shell 92 octane.

I think I have listed all the important factors here. what do you think? if it is just a rod bearing, can I just replace it?

what are the odds that I dont have to pull the crank?

Thanks

Shane@DBPerformance
05-21-2008, 02:31 PM
How much timing did Keydiver remove from your chip, did he know it was a 9.5:1 motor? Factory 1G timing is way too much for even a 8.5:1 compression engine. Running 11-12psi wouldn't make it safe either, at lower load often runs even more timing depending on where you land in the timing map. A 9.5:1 compression pump gas DSM wouldn't be able to take barely any timing/boost without knocking. Did you pull the spark plugs and check for detonation the plugs and piston tops? Did you set the base ignition timing? Did you have a wideband on it?

Shane@DBPerformance
05-21-2008, 02:33 PM
You shouldn't have been running it with too much oil either, that isn't good. Have you changed the oil/filter a few time in the ~500 miles? Did you have non-synthetic and thick enough oil in it?

Speedfreak
05-21-2008, 03:16 PM
What Shane said^^^.

But no chance of leaving the engine in place. You now have shavings floating around everywhere, and the crank will probably/possibly be damaged(as could be the rod). Complete rebuild is in order.

v8klla
05-21-2008, 03:20 PM
Alex,

I'm sorry to hear about your difficulties. I think you are referring to the motor you purchased from Bill correct? I'm pretty certain that Bill assembled that with Kyle's guidance, but in any case we would love to take a look at it as we have yet to spin a bearing or have a failure of any sort in our shortblocks.

Also, can I ask what you were revving the engine to? I recall you saying it was somewhere in the 9k range when you were last in?

Chris Carey

blageo23
05-21-2008, 03:31 PM
Im not an expert but I do have some experience with blowing up engines. Both times I had metal flakes in the oil my crankshaft needed to be replaced as well as all the bearings.

DSM_421
05-21-2008, 03:51 PM
You shouldn't have been running it with too much oil either, that isn't good.

I always knew this, but never why. Is it because you will have too much oil pressure?

Kracka
05-21-2008, 03:53 PM
Overfilling too much can cause the crank to drag in the oil creating extra resistance and also causing the oil to foam. I'd say a 1/2 quart is not a big deal though as it shouldn't be enough to interfere with the crank.

scheides
05-21-2008, 03:56 PM
Also, can I ask what you were revving the engine to? I recall you saying it was somewhere in the 9k range when you were last in?


Wow, 9k and only 12psi? what on earth for? RPMs could be your cause of death here, my friend.

iceminion
05-21-2008, 04:03 PM
I mentioned that Modern built my engine....so that you would all know that the workmanship was perfect and you could RULE OUT my in-experience.

I revised my first post

-------------

8k max.

will take a look at the crank later tonight.

didnt know that the stock timing tables were too much.

Kyle did recommend that I run wastegate pressure (which I am doing, lightest spring) I guess I should have also said that I was not running any kind of professional engine management. Chipped/SAFC, was planning on using 'squirt or link before I made any more boost.

I assmed my new knock sensor would have retarded the timing enough.

Guess I was wrong.

Sooooooo, now what? assuming that the crank cannot be re-used.

Can I turn the crank? re-apply the nitride coating?

I do plan on going megasquirt, so I will have full control of the fuel AND timing.

what do you think?