Hello group,
Just thought I would give a little update on the New Mexico "desert
rats" running the SVX Ivo prop combination. Last you heard from me we were
running the standard pitch (30*-90*) 76" dia. magnum prop. We initally
thought this may be a little too much prop and that we may have to send it back
to Ivo to have an inch or two trimmed off. NOT, we set the prop in neutral
position (60*) and ran the engine up expecting to get 2200-2300 rpm at full
throttle. It went to 2800 RPM without even reaching full throttle! I talked to
Ivo the next day and he suggested I go to the high pitch blades (45*-105*),
which he exchanged for me and did an upgrade on my gear motor at no charge. The
new blades and motor came in less than a week and we were ready to test them
again.This time the run-up numbers looked great, at the flatest pitch I was able
to get 2475 RPM at the prop, full throttle and it still runs smooth as
silk. I added the spacers as per instructions to give me a max. static RPM of
2400.
We had a minor cooling problem because of air being trapped in the system
right at the water pump. Taking one of the small water lines loose near the top
of the system seemed to work well to vent most of the air out along with coolant
being sucked back into the system from the overflow as the engine cooled. With
that resolved we were able to run the engine at various RPMs from idle to full
throttle for about 20 min. before getting high coolant temps.(225*).We're
running a Griffen all aluminum racing radiator 15"x 19"x 2.5" and
an aluminum heater core 7"x 7"x 1" with a couple of bilge fans
plumbed to it to give cabin heat as necessary and additional cooling, especially
during taxi. Any of you other builders using a Subaru SVX be advised it needs
alot of prop, especially if you want to keep your prop RPM at or below 2800 RPM.
Well, now that I've had my fun with the engine and prop it's back to
sanding and filling (re-countouring the cowling to fit this engine, PSRU and
prop a few "speed bumps" had to be added)
Regards Lino