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Re: S4 20v vs S2 10v

   > (I suspect it also means you can charge five times as much for a tune-up
   > since you have five times as many coils to tune, right?)

   for sure, but do coils get routinely replaced?  labor to replace
   spark plugs will probably be more..

So what's actual work performed got to do with how much the dealer can
get away with charging poor dump customers for a "standard tuneup"?
I mean "you have the high-performance engine with a much more complicated
engine management system, it's much more expensive to 'tune up'", even if
in fact there is *nothing* to do other than replace the air filter every
30,000 miles, and maybe the spark plugs and O2 sensor! (In case it's not
obvious, I don't have a very high opinion of most "dealer" shops -- al-
though I must admit that both Mitsubishi dealers I've dealt with seemed
competent enough...)

   > At 20:1 you can dispense with ignition altogether (you have a
   > diesel engine). 

   hmm the S4 has a 9.3 compression and 2.15 bars would make it

   i wonder how they keep this baby from blowing its brains?

Probably very very carefully . . . (knock sensors help a lot! One guy I
meet once a coupla years back had fitted a Saab APC unit to his UrQ. It
was kinda fun to watch the APC unit modulating the boost in the 15-17
psi range . . .)

   how about the 1987 formula 1 cars that ran 4 bars of boost..  i think
   they had compression ratios of 6.5 or thereabouts.. which means 26:1

Not to mention "zillion-octane" racing fuel . . .

   > Now if you had direct injection . . .

   how about sequential injection that the S4 uses?  how does that
   affect things vs. simple CIS?

Probably not a whole lot; it allows a slightly better overall metering
of the fuel than CIS (and in particular, flows fuel only when the air
is also known to be flowing in the desired direction!). Mostly it al-
lows one to dump that horrendous CIS fuel distributor and all its awful
plumbing and other Rube Goldburg accouterments, giving the computer di-
rect (and instantaneous) fuel mixture control over the engine.

MOA. [In this particular case: My Opinion, Anyways]