Thanks for the update, Rino.  You are definitely doing ground-breaking
work in our arena.

snips....

BTW, did you fabricate your own intake manifold or sub it out?  I'll be
building one for my Renesis -- haven't decided on using aluminum vs.
molded CF for the upper manifold yet.  My engine is still at Bruce's
getting the final touches.

Scott Gettings

Scott what all are you doing to your Renesis? What are your manifold plans?

Ken

Ken,

I bought a Renesis with 2K miles on it from a Rx-8 getting a 3-rotor
conversion.  It is currently in Bruce Turrentine's shop.  He is doing
all the standard internal modifications, such as replacing the side
seals, doing some porting, adding silicone to dampen the tension bolts,
as well as lightening, etc.  The internal variable intake tubes will be
ported, then set-screwed in place to optimize about 7K rpm.  They can
be adjusted if needed.  Redrive and ECU will be Tracy's.

I plan on cutting off the  lower intake manifold (exact position not
yet determined), and weld on 4 elbows to keep the profile much closer
to the engine than stock.  From the elbows, I'll have 4 runners flow
across the block, with injector, a plenum and throttle body on the cool
side (similar to many existing installations).  This upper manifold
will most likely all be carbon fiber and high-temp epoxy, but I haven't
completely ruled out welded aluminum yet.

Having had considerable composite experience, I'm pretty confident I
can build plugs, molds and produce a manifold with smooth internal and
external surfaces from carbon fiber.  The plugs will be built from foam
or paraffin wax, 1/2 at a time (upper and lower surfaces.  The bonding
between the upper and lower runner products will be a flat flange that
runs between the tubes.  So the upper side looks (roughly) like:
_/\_/\_/\_/\_     The flanges also allow mounting surfaces.

Blending in bell-mouths and the plenum chamber will be a little tricky,
but is not beyond reason.  I might build the plenum chamber so that one
could attach a throttle body on either end, making it useful for
pushers or tractors.  Positioning the injectors on the side  of the
plenum chamber (pointing at the bellmouths) would allow a much easier
installation than fitting them against the curved edges of the runners.
The latter case is easier in aluminum, but can be done with a
composite version.

The downsides of epoxy/CF are that it needs to be strong enough to
withstand a backfire (anyone want to estimate a psi from a backfire?),
it is a little difficult to integrate metal components, and it is
eventually capable of burning (but so is the cowling).  I'll have
multiple temperature sensors and a fire-suppression system to mitigate
the latter.  Regarding a backfire, the weakest area of the manifold
would be the bonding flanges, which could 'peel' apart long before the
tension of the carbon fiber was exceeded.  If I have a optional
position for the throttle body, this (unused) end of the plenum could
be capped with blow-off capability at a certain pressure.  Some
secondary CF tapes placed at the bond line inside the runners might
also be possible (at least in some areas), or a secondary internal
flange that spans the bond line also seems possible.

Pending issues:
1. Exhaust:  probably three, 321 pipes to a tangential muffler,
exhausting at the prop hub area.

2. Thermostat:  Bruce wasn't certain if I should use a restrictor
plate, keep the thermostat, or modify it to accept no restrictions at
all.  I haven't seen the internals on the RX-8 pump yet

3. Cooling: using Paul's concepts, with internal ducting.  Large, thin
main radiator up front and the oil cooler below the engine.  There
should be more than enough frontal intake area to handle the main
radiator, oil cooler, intake, and exhaust tube.  This will have to
follow the engine installation.  I'll probably be able to shrink the
original cowling once everything is optimized.

This will keep me busy for a long time!

Scott Gettings