[PedroAgua]

Gang,

I'm retro-fitting a Airflow Performance system into my RV-4. Due to the tight spaces of the -4, my mechanic and I have decided to put the Airflow fuel pump and filter into the battery case, and, since I've also got an Odyssey PC-680 battery that I'll be using instead of the old Concorde, put the battery in the baggage compartment. (Since the airplane was built in 1988, there's too much stuff on the firewall to mount it there... we'd be doing surgery and metalwork for months.)
I realize that I'm moving the CG aft, but the -4 has always been nose heavy. I've got an 0-360 with a Catto 3-bladed prop; it'll soon be an IO-360, of course, and once I'm satisfied that the fuel-injection system is wrung out, I plan to swap the Catto prop out with a two-bladed Prince P-Tip to get better cruise speed.
Obviously I'll be re-computing W&B, but my question is: does anybody have experience putting an Odyssey battery in the baggage compartment of a -4? I realize that that location, with the cable run and all, is not ideal, but it seems to be the best option. With the weight of the O-360, I tend to run out of Gross Weight before I run out of CG.

Thanks,
Pete

 

[N999BT]

I wouldn't

I put my odyssey in the right cowl cheek. Works great, short wiring runs, etc. I mounted it with adel clamps on the engine mount. I have an O-360, Catto 3 blade. This configuration does make the stick force in pitch a little higher than it used to be pre battery move, but much better CG range. YMMV.

 

[F1Boss]

Keep it fwd somehow

Hey Pete:

I don't think you'll be happy with the batt aft - your luggage cap will drop dramatically. One the plus side, the ship will be more spirited when flown solo. The 680 is mounted on its side under floorboard (pilots rt knee) on the F1 Evo - maybe you could squeeze it in there on your plane also?

Carry on!
Mark

 

[Jaknjoan]

I have my Odyssey in the baggage compartment

Gang,

I'm retro-fitting a Airflow Performance system into my RV-4. Due to the tight spaces of the -4, my mechanic and I have decided to put the Airflow fuel pump and filter into the battery case, and, since I've also got an Odyssey PC-680 battery that I'll be using instead of the old Concorde, put the battery in the baggage compartment. (Since the airplane was built in 1988, there's too much stuff on the firewall to mount it there... we'd be doing surgery and metalwork for months.)
I realize that I'm moving the CG aft, but the -4 has always been nose heavy. I've got an 0-360 with a Catto 3-bladed prop; it'll soon be an IO-360, of course, and once I'm satisfied that the fuel-injection system is wrung out, I plan to swap the Catto prop out with a two-bladed Prince P-Tip to get better cruise speed.
Obviously I'll be re-computing W&B, but my question is: does anybody have experience putting an Odyssey battery in the baggage compartment of a -4? I realize that that location, with the cable run and all, is not ideal, but it seems to be the best option. With the weight of the O-360, I tend to run out of Gross Weight before I run out of CG.

Thanks,
Pete

I mounted my Odyssey battery in the baggage compartment of my RV-4 equipped with an 0-360 and Hartzell C/S. I also increased the baggage area volume by removing the step over the bellcrank, extending the floor aft slightly and then building a sturdy little "dog house" just over the bellcrank. The idea was not to put more weight back there, but have more cubic area. The "dog house" is removable, to inspect the bellcrank and pitch servo, by removing 4 #8 flush screws that are secured by nut plates.

I did the baggage area modifications at the same time I changed my turtle deck skin to fastback skin. I used Harmon Rocket aft bulkheads, slightly modified, and a Todd's Harmon Rocket canopy bubble.

My empty CG is 70.29 inches aft of datum.

JT, Independence, OR