changing engines

[dan carley]

i'm thinking of changing the engine in my rv-4 from a 0-320 to a io-360. are the same engine mounts used? will you need to change the cowling to fit a 360? what else would be involved? has any one done this? is it worth it?

thanks
dan carley
RV4
N14FT

[Steve Barnes]

Depends,if its an angle valve engine, big changes are ahead.

[N941WR]

Dan,

Doug changed the engine on his RV-6 a few years back. You might want to do a search on his name and see what comes up.

[rv7charlie]

Some 320s (including mine) are conical mount; others are dynafocal. I *think* that just about all the 360s are dynafocal. If you have a dynafocal 320, a 360 dynafocal should bolt up to the mount.

Can't swear to it for the -4s, but on the -7s the 360 mount is shorter (firewall to back of engine) than the 320 mount to keep cg in the right spot with the different weight engine.

Charlie

[Bob Axsom]

Rusty Hall had a 360 in his RV-4 that he flew in the Rocket 100 but I do not know if it was the 200 hp 360 cu. in. version. If you go to that engine I think you have to consider it a major project. I also am thinking of such a change at overhaul time. I expect a lot of custom work like a new cowl. I am preparing myself to construct a full male mold with with imbedded precision fuselage station templates from the rear end to the forward end to get the mold lines and internal clearances just right. The systems installations will present the same kind of choices that were involved in the original build with development, integration and test. I plan on sticking with the LASAR ignition system that has worked well for me and a new Hartzell C/S prop with the older F7496 blended airfoil blades. After all is done the weight and balance and flight test will have to be redone to characterize the airplane's performance. A big price to pay but I've got to catch John Huft.

Bob Axsom