RV-6 Engine change - Page 2

Mike S · #11 12-14-2015, 08:27 AM

Quote:

Originally Posted by N710B

Hi all,

I'm new to the group and just purchased an RV-6

Dave

Dave, welcome aboard the good ship VAF

Congrats on the new 6.

Mel · #12 12-14-2015, 08:34 AM

Like Sam says, the -E2D has a hollow crank but won't allow for C/S because of the front bearing configuration. High compression pistons are the simplest way to increase hp.

grubbat · #13 12-14-2015, 10:44 AM

All things considered, I agree with Mel and Sam. I had a 150hp and changed the Pistons to 9:1 along with heavy wall pins. It really brought the engine to life and turned a good cruise prop into an great all around climber.
No changes to structure and didn't have to change carb either.
Cj

WA85 · #14 12-14-2015, 12:26 PM

The potential 20-30 hp performance gain may be marginalized by the high cost of swapping out a perfectly good O-320, the minimal performance gain, the added 25 lbs fwd of the firewall, increased fuel usage, time spent re-engineering the swap and time spent in Phase 1.

Keep it light and simple.

Possibly put a Catto prop on your current configuration, it may provide additional performance for minimal effort and cost.

PCHunt · #15 12-14-2015, 02:46 PM

Quote:

Originally Posted by Sam Buchanan

My E2D has a hollow crank but the case isn't machined for a governor..................

Sam, if you have a hollow crank, wouldn't that change the engine designation? I thought that by definition, an -E2D has a solid crank...

Mel · #16 12-14-2015, 02:54 PM

Quote:

Originally Posted by PCHunt

Sam, if you have a hollow crank, wouldn't that change the engine designation? I thought that by definition, an -E2D has a solid crank...

Where did you see this? I've never seen an -E2D with a solid crank.

PCHunt · #17 12-14-2015, 06:11 PM

Hi Mel, I bought an RV-6A with an O-320-E2D installed, and was told it had a solid crank. I have been trying to find something online that would state which crank it has, unsuccessful so far.

I do see that it has an O-235 front bearing on that crank, and I assumed that meant solid crank?

Waiting to be properly educated!!

DaleB · #18 12-14-2015, 06:29 PM

Quote:

Originally Posted by PCHunt

Hi Mel, I bought an RV-6A with an O-320-E2D installed, and was told it had a solid crank. I have been trying to find something online that would state which crank it has, unsuccessful so far.

https://en.wikipedia.org/wiki/Lycoming_O-320

Might not be perfect, but might help.

scsmith · #19 12-15-2015, 11:01 AM

Along with what others have mentioned here,
The motor mount is different for the 360....it is a bit shorter, to keep the c.g. in the right place.
Whether that moves the crank flange back, I don't know for sure. But I suspect the cowl would have to be changed (either because of this, or because of the width increase and carb location, as mentioned by others).

So, engine mount, baffles, cowl....its pretty much a complete re-do of the FWF.

On the flip side, if that O-320 is not making metal, and has good compression and not burning too much oil, just keep running it. I'm not convinced they ever truly "time out". I've owned a Citabria with a 320 that we decided we should overhaul after 3200 hrs. It was pretty much like new inside.

On the other side though, I've known of an O-320 that went downhill very fast at 1400 hrs with dramatic loss of power, high oil consumption and metal in the oil screen.
The difference was it was left to sit unused for a prolonged period and then returned to hard service. I think it was a camshaft rust problem.

And when it does come time to overhaul, some of the options suggested here will get you a nice boost in power.

az_gila · #20 12-15-2015, 12:01 PM

Quote:

Originally Posted by scsmith

Along with what others have mentioned here,
The motor mount is different for the 360....it is a bit shorter, to keep the c.g. in the right place.
Whether that moves the crank flange back, I don't know for sure. But I suspect the cowl would have to be changed (either because of this, or because of the width increase and carb location, as mentioned by others).

So, engine mount, baffles, cowl....its pretty much a complete re-do of the FWF.

.....

I think your motor mount comment is for the RV-7 series only.

The RV-6 motor mounts are the same for O-320 and O-360 engines. I changed in mid-build with no mount problems.

There are two cowl lengths though depending on the length of the prop spacer, and the depth of the "carb scoop" between the two models changes, but a replacement scoop is available that can be spliced onto the existing cowl.