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MetricMechanic motor thoughts

Michael Stenman wrote:
> Subject: 325e modifications

>article did not say was how much it cost to have MM get 200 hp and 200 t*lb
>of torque. I would rather rebuild what I have if I can for a reasonable
>amount. Basically if it costs $10 K then I might as well look at a 325i.
>I welcome any wisdom or insight anyone has. Is it worth it to try and cnvert
>the eta to M3 level performance?
>                       Michael Stenman

	Back to the MM motor: they use the good old hotrod trick:
Nothing beats cubic inches...  except cubic dollars...

	They show some flow mods which are at best dubious, but hey, 
they warrantee the damned things.  
	MM usedta just sell hot heads and trannies.  Then they went
to higher-displacement motors to tame the cams.  They use long rods
and lightweight reciprocating and rotating parts (rods, pistons, and
flywheel) to get usable high-rpm power with decent midrange torque
	The big thing now is their "Surface Turbulence" [tm] work:
the intakes are cut with circular grooves on the back and face of the
head to create better flow and some combustion chamber work to make
the head swirl/swish/sashe' better. I gotta wonder how the longevity
of an intake valve is affected when you cut grooves in it: the word
is "stress raiser" for any place that invites and concentrates stress
and strain: sharp edges, grooves, corners, etc.  That's why you have a
smooth edge on the dome of your 10.0:1 piston and you smooth machining
marks on your rocker arms and connecting rods. Less can be more, if it 
is smooth.  
	They claim (in their ads, of course) that flow is improved like
3-5% over their already good-flowing heads (they claimed 13% on their 
head over stock, 22% with a 278* cam they were selling) and improved
burn for better emissions and economy!!!
	Now, I'm wary of any company that claims their 2002 E12 head
with hot cam outflows an M3 head.  But the numbers they put up vs. a
stock head was incredible---nearly 25% more airflow.  One reason I
don't like Korman so much is that their catalog had a snotty comment
about MM's tech tips back in about '89 regarding budget rebuilding a
race 2002/320i motor.  

				thi v., running off at the mouth again