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<02> No Power = Dead engine :(

     Here's my tale of woe.

     Over the last three point five years I rebuilt just about everything
     on my '75 2002.  This included the engine and transmission, with the
     help of a freind who has done numerous engine / tranny rebuilds since
     he owns 5 2002's.

     The tranny is a stock four speed.  The engine has 9.5:1 pistons, 294
     cam, dual valve springs, 40 DCOEs, MSD coil and 6A, Pertronix magnetic
     pickup (in lieu of points), ti mechanical distirbutor, header.  When I
     rebuilt the engine, everything was new except for the valves, crank,
     block, rockers, rocker shafts, head and the associated cover plates
     whinc all were in spec.  The block was bored to first over size,
     bringing displacement to 2020.  The oil pump, chains, gears, gaskets,
     pistons, rings, seals, crank pulley, water pump etc. were all
     replaced.  I guessed that all this was worth around 140-150 HP.

     The car has never pulled as strong as I think it should, especially
     since the AC, front bumper and interior are removed (except door
     panels and the drivers seat).  I figured the engine was still breaking
     in it would get better.  Two weekends ago, with the odometer reading
     700 miles since rebuild, I finished my last of three autocross runs
     with a strange knocking noise.  I checked the gages, saw nothing and
     drove home carefully.  I adjusted the valves that night and checked
     the head assembly.  Valaves looked OK and #4 spark plug was black.  A
     quick check of the mixture screw revealed that it was one turn out
     from the other three.  I also discovered I had the classic #3 header
     pipe broken.  I thought that was the source of my noise.  BTW, I beat
     all kinds of Pee cars and an E30 M3 that day.

     This weekend I went to another autocross, the engine noise was worse,
     I figured the header was really breaking more.  After the first run I
     had the fastest time of all the BMW's and was near the top of the
     field.  Again, the car did not pull and sounded really bad (loud
     knocking) as I pulled off the course.

     I was going to stop for the day but a fellow 'cca member in a Dodge
     Neon beat my time, as did one of the E30 M3's in CSP.  I went out
     again, this time blue smoke coming from my tail pipe.  My time was
     slightly better, but the car was definitely bad off.  I limped home
     and pulled the oil pan.

     Inside I discovered lots of bad things in the form of bearing shards.
     A quick glance at the crank revealed the #4 rod bearing was extruded
     all over the place and there was all kinds of slop in the rod (my real
     source of noise).  The other rods looked ok.  I pulled the #4 bearing
     cap and found pretty severe scoring of the crank surface as a result
     of a spun bearing.

     I pulled the engine and tranny yesterday (tranny had since gone for a
     profressional rebuild since I botched that also and can't keep second
     from crunching).  I pulled the head off today. Cylinders 1-3 look ok
     in the camber, slightly brown in color.  #4 is definitely black.  I'm
     hoping the rings are ok and the oil got past them as a result of the
     slop at the rod.

     Here are my questions:

     I think the jetting is close on the carbs, what else would cause a
     lack of power?  Will a 'tight' engine feel like it has no power?

     I'm now sending the engine to a pro for rebuild.  It will more than
     likely need a new crank and possibly rod(s).  I'm hoping everything
     else (except bearings and seals) can be reused.  Does anyone have a
     used 2 liter crank with no scoring on the bearing surfaces for sale (I
     don't want to pay more than $100)?  I took a look at one yesterday but
     found ever so slight scoring on one surface, no deal.  I still have
     one more resource for a crank, but it will take some doing to get it.
     I'm just a little paranoid now about this, since I have no idea what
     happened as a root cause of this mishap.

     If I locate a E30 M3 crank, was else needs to be changed to make this
     thing work in a 2002.  Fly cut pistons, custom rods?

     Well at least the M3 is running for O'fest.

     matt brumwell
     '75 2002 autocrosser sans engine and tranny
     '87 535is sans tranny
     '88 M3 basement queen
     '87 mustang lx, 2.3A.  At least I don't have to do anything but add
         gas and change fluids