any one played with MR2 superchargers?

[Steve N.]

> specifically, anyone ever taken one of these off the MR@ and used it
> somewhere else, like say a rotory.  From what I've read about them they
> aren't to big, and have a very nice blowoff valve/SC bypass system built
> in. Plus they have the electronic cultch built in the pully.  Any experts
> on these guys? 

Well, not really an expert, but mr2 mailing list veteran of 3 years,
owner of the AW11 (body name for MKI Mr2) Archive, and own an 87.  First
off, you can go to my page at the bottom and get some more info on the
SC.  There is also and SC dedicated web page. www.mr2sc.com  Both pages
have a tech article written up about the SC.  The SC itself cannot flow
much over 210-220 HP.  The stock boost is around 7-8 psi and the HKS
pulley will get you around 10 or so.  There are also two other pulleys
that are made for the SC, one by Blitz that will give around 12 and one
by Cusco that gives around 13-14.  The Cusco pulley requires
modification to the Mr2 engine for the pulley to fit right.  Obviously
the psi is all dependent on the engine it goes into, as modifications to
the Mr2 head to increase flow will bring the psi down, as the SC simply
flows a certain amount at a certain rpm based on the pulley ratio. 
Either way, the air coming out of the thing at these temps are VERY VERY
high.  It has been said that for the stock boost they run, the SC is
pretty good, and a good inter cooler will help some, but above the Blitz
pulley you are going kinda on the ragged edge.  At this point, many Mr2
owners are running around 170 Hp on an unmodded engine.  With flow
improvements you can get to the 195-210HP range.

> try asking this on the mr2 list (thnk its at mr2.com)

Yes, there are some knowledgeable people there, but most don't know
actual specifics about the SC.  Most people just swap entire SC engines
into their car and don't worry about the SC itself.  Actually, there was
an FSAE team a few years ago that ran one of these things on a Honda 600
if I remember correct...

> they probably do not flow enough air for a rotary

This is where a twin charging system comes in.  A notorious kit for the
Mr2 that was once made by HKS was the twin charger kit.  It was
basically a turbo kit that went onto the SC engine.  There were
something like 5 kits sold in the Us and they ran around $6k.  HKS is
often refered to as HK$.  Their stuff is often good but usually VERY
expensive. There are only 3-4 twin charged cars known to exist.  There
are two in highly modded states that run around 300-350HP.  Woners of
the kit often had problems with trying to get both the SC and the turbo
to spool up at the right times.  The SC would come up quick to kill lag,
and then the turbo would hit.  You had to get the SC to hit just right
by using the clutch system on it, then have a good turbo curve to keep
the power band at least somewhat smooth.  One of the guys I know that
has one, is currently trying to find a way to let the SC kick in when
you first hit the throttle, but then bypass the SC once the turbo gets
spooled up.  If you want to use this on your rotary, this would probably
work.  I have some more info on the twin charged cars on my page.  I
also have some more stuff, but have not had a chance to update the page
in a while....


Steve N.
AW11 Archive: http://www2.msstate.edu/~sgn1/MR2/mkimr2.htm