This is the second M42 build for E30 MotorWerks. Like the first one it sounds great and runs like a champ!
The following basically outlines how I build all my engines.
The customer declined any paint so the engine is 100% natural. You guys may have seen the yellow and black bumble bee M42 that was the first one we built.
The engine had expired due to a failed chain rail. The pieces fell down into the crank gear slipping the chain and bending all the intake valves. The front cover had been seeping and damaged the front face of the block. The crank was starting to get a damaged thrust surface and was caught just in time.
The rebuild is mostly stock. The head was given new intake valves, surfaced and standard valve job. The block required mill machining to save the front face of the block. The rods where completely reconditioned including polishing the side beams and shot-peening. The front cover was replaced including new oil pump rotors, cover plate, and updated oil relief valve components. The main caps where custom machined by Metric Mechanic to accept 360* thrust bearing, and 360* oiling grooves for improved rod bearing oiling. The rod bearings are custom NASCAR performance shells that can handle a whole shit load of abuse as used in a NASCAR Cup motor. Of course all new timing components, and I mean all new as in every single peice, chain, guides, tensioner, gears, idler, etc..
Almost all critical internal components are from the dealer as alot of them are superseded in design.
And on to the pictures. I have a whole bunch of them but I think these will tell the story well enough.
Damage pictures first:
Blown original style chain guide. This peice has been superseded to a better design to prevent such failures. Notice the piece with the teeth marks in it? Thats the one that rolled through the chain taking it out of time.
Wasted front cover with rust and chain damage.
All 8 bent intake valves. I used the box in the background so you can compare the straight printed text to the bent valves.
Now for some of the build shots:
Machined front face of the block. Notice there is still rust damage but it doesn't interfere with proper sealing. Before it was really bad. This block was barely savable. We took .010" off the front, max as stated by Metric Mechanic is .015", after that you get into trouble with the crank and oil pump interference.
All new front cover and oil pump components, all dealer parts.
Reconditioned, polished, shot peened rods, balanced, etc..
Crankshaft after being magnafluxed, polished and oil holes chamfered for improved oiling.
Clean and rebuilt cylinder head.
In the end it looks just like a standard M42. You would never know it was completely rebuilt by looking at it.
And finally, it runs smooth and crisp. Once it breaks in it will run even harder!
Topic: Another M42 rolls out. (Read 6678 times)