Re:<E36 M3> Over-rev... have I done it?

["Greg Koenig" <gregk@xxxxxxxxxxx>]

I have a bit of experience with this little problem.

I over reved my 325is on the same shift (3rd to 2nd instead of 4th).
Everything seemed just right fine.  No strange noises, no power loss, no
tapping sounds no problem starting.

2 Weeks later, downshifted to second at about 50mph to take an offramp and
as I apexed and got on the gas, KA BOOM!  I mean, this thing done blown up.
some fun facts: 4 inch hole in the block at piston 6, big enough you could
reach in and grab what was left of the connecting rod.  Where was piston 6?
well, we found most of the parts of the piston in the exhaust.  Looking up
with a mirrior towards the head, we found the intake valves still there,
however, the only remaining part of the exhaust valves were two stems.
Metal shavings were found in the air filter... basically a very bad day. I
still have a ziplock bag filled with parts of good old piston 6.

My shop thought it was oil starvation to #6 (I didn't think the over rev had
anything to do with it, remember, there were no problems after the over rev,
I had pretty much forgotten about it).  Calling around for a new engine
(after a but of a mess about putting in a Euro M3 engine) I got to talking
with the likes of Kermit Upton, Will Turner and TC Kline, all of whom told
me exactly what happened.  To sum it all up, after the over rev, I was
living on barrowed time.

So, Mike, not to take an alarmest view on this one, but if you want some
cheep insurance, get the car over to a good shop, and have they tear apart
the head.  You are going to spend about $1700-2000, but it is the only way
to be sure that something very bad didn't happen.  Let me put it this way,
you get to spend $2k now and you will be OK, or you have a VERY HIGH
likleyhood of having to spend $6-7k in the next couple of months.  Hell,
while you have the head off, you could even do some performance stuff to it
(porting and polishing, valve job, titanium retainers, new piston rings,
better head bolts).  With the help of someone like Jim C or Turner, you
could get a good 280bhp out of a well built head.  You will probably pay $4k
to get all this fun stuff done, or you can spend $6k (or more) later on just
to get your car running again... your decision...

Greg Koenig
BMW CCA GGC
Dinanstein Pilot
San Francisco Street Terror

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