I am about to install a Precision Airmotive Silverhawk vertical draft FI on a 0360 Lycoming on an RV7. My project came with MA 4-5 carburetor and I have already prepared the firewall penetrations for that carburetor. I would like to be able to use the penetration points if possible. I have read post about the standard clockwise mixture control (control arm points down) requiring modification to FAB. I cannot find any post relating to the alternate Counter clockwise version ( arm points up). Any help with info on the alternate (up arm) would be appreciated. Actually I would love to hear about either installation. If down arm, how you solved the interference with FAB, and how you like the Silverhawk system, any problems with the Silverhawk. Thanks.
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help with Precision Airmotive Silverhawk vertical draft Fuel Injection
- Thread starter Flyyak
- Start date
FlyYak,
I have the SilverHawk with the standard arm down config. I received it with a straight arm but had FAB interfernce. I traded for a bent arm and it works fine. Still a little FAB adjusting but it works fine. Still very close to the cowl. If you prefer the up arm it requires a complete servo re-configuration from Precision.
Precision has a good website with info on the different arms and configurations available.
Been working great.
I have the SilverHawk with the standard arm down config. I received it with a straight arm but had FAB interfernce. I traded for a bent arm and it works fine. Still a little FAB adjusting but it works fine. Still very close to the cowl. If you prefer the up arm it requires a complete servo re-configuration from Precision.
Precision has a good website with info on the different arms and configurations available.
Been working great.
jthocker
Well Known Member
I recently swapped a carb for an Avstar injection system ( functionally the same as the Siverhawk).
Your firewall penetrations should work fine (although mine is an RV8).
Alternate Mixture control(arm up) will also need an offset arm, otherwise the rod end bearing will contact the full rich stop ahead of the mixture arm, precluding full travel of the arm.
I used a 7/8 inch spacer to align the shorter height fuel servo with the existing cowl scoop. With that spacer I would have been able to use the standard mixture control(arm down), but didn't know it at the time.
Good luck.
Thanks. I have read that the fuel servo is shorter than the MA 4-5 carburetor and others have used a spacer. The standard configuration (down arm) is less expensive. If I use the spacer, will I need to request a bent arm or the straight arm. Any chance that you are anyone may have photos. Thanks again.
Aerosport Power IO-320 w/ Silverhawk
My IO-320 came from Aerosport with the "up" mixture arm. I was not able to route the mixture cable via the Vans-indicated firewall location, i.e. even the longest Vans mixture cable wouldn't reach. I relocated the FW penetration to the center inset on the firewall ... that worked like a charm.
I find the Silverhawk a joy to fly. Starts easily hot or cold (once you learn the right protocols),and is delightfully precise in terms of adjustments and response. Cold starts fire on the 2nd blade EVERY time.
My IO-320 came from Aerosport with the "up" mixture arm. I was not able to route the mixture cable via the Vans-indicated firewall location, i.e. even the longest Vans mixture cable wouldn't reach. I relocated the FW penetration to the center inset on the firewall ... that worked like a charm.
I find the Silverhawk a joy to fly. Starts easily hot or cold (once you learn the right protocols),and is delightfully precise in terms of adjustments and response. Cold starts fire on the 2nd blade EVERY time.
