[Normy]

That's not good~

I've not had any blocks bored or stroked, or even refinished, which is what the 928 block [M28 is the engine term] needs.

I've read that this block needs to be "lapped" when it is done being bored out. They put a special felt pad on a hone and it causes the aluminum to be worn away, while the silicon crystals [sand] resists and stays in place. The result is that the worn sand particles in the Aluminum block remain and this is what your iron rings ride against...with nearly NO resistance since the oil film will NOT soak into silicon. If they don't do this special procedure, then you will be burning more oil than fuel within a few thousand miles!

-chevrolet foisted a GREAT car with a WEAK engine on us in the early 1970's, and it was a recall-nightmare because they didn't get the honing and silicon content correct. Porsche learned DIRECTLY from this fiasco, and every 944, 924S, and 928 are a testament to this.

This is a SPECIAL engine. It is litterally bulletproof in use! You can't break this motor, as long as you keep it below 6200 rpm.. But it has to be handled carefully when rebuild time comes.

Best of luck!

N!