Motor-vation

G'day Everyone,

For the last few years I have been lurking around and reading the plethora of great threads as I build my RV-8. Well I finally have something neat to share. Last weekend I picked up my new motor. It started out as a Superior IO-360 kit that I had Lycon assemble for me. It came with dual P-mags, cold air induction and fuel injection. Lycon added 10:1 pistons, port and polished the heads, 380 CID stroker crankshaft, o-ring case seal, a lightened flywheel and a slightly re-profiled camshaft. The stroke was lengthened by 0.200" so by my math it is actually 377.5 CID but 380 is easier to say fast. There was a bit of a wait for pistons as they needed to have the ring location changed from the standard location. Anyway I am happy to have it and it worked out to be within $1,000 of a stock Lycoming from Vans. Lycon did the initial break in and a dyno run and the net result was 236 hp and 454 ft.lbs at 2700 rpm corrected to standard sea level conditions. So it should get up and go just fine. I fly helicopters in my day job so anything faster than 90 knots and higher than 500 feet is going to seem blisteringly fast to me. Hopefully attached below are a goofy photo of me and the motor and a graph showing a time history of the dyno run. The engine was run up to 2700 rpm at full rich then leaned 100F for the last part. Not sure how 100F lean of full rich is compared to peak but it made an extra 10hp in doing so.

http://i1272.photobucket.com/albums...0-3d1d-4bd6-838c-304ea0d05c34_zps8aac6a74.jpg

http://i1272.photobucket.com/albums...8-252f-4ea5-8628-932ae30d0dbf_zps1f5604a1.jpg

I'd like to think I will get it flying by the end of the year.
Cheers
Nigel

The images

Sorry for not attaching the images directly, seems I have some progress to make in reading instructions.





Cheers

Very cool!

10:1 is some pretty high compression for one of these engines. I thought I was going high at 9:1

With that much compression and P mags, you should do some research on the propeller you choose. Both compression and ignition can alter vibration issues.

John Clark ATP, CFI
FAAST Team Representative
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA

Nigel,

If you ever need a hand with anything, let me know. I'm in town about 5 minutes from the airport.

Flywheel

Where did you get that flywheel?

How much lighter is it than stock?

Is there machine drawings for modifying a stock flywheel to this set up?

I am assuming it would change the harmonic vibrations some.

Lightweight flywheel

Lycon did the machine work to lighten the flywheel. It started out as a stock Superior part.

I think a stock one weighs approx. 7 lbs. and this one is 2.5 lbs. lighter. Mine still has the alternator pulley. They make them for aerobatic aircraft with rear drive alternators and for this application they machine the pulley off as well for even lighter weight.

I don't have the drawings but Lycon charged me $150 for this mod as part of the complete engine build.

Changing the mass of the rotating assembly will most probably affect any harmonics/vibrations. But assuming the prop and flywheel are rigidly bolted to the crank flange there should be no more affect than changing the prop weight and folks fly with a wide range of prop weights on these engines. My plan is to have the prop dynamically balanced prior to first flight.

Regards

Nigel

230 hp! That graph made me drool....

Lots of HP

Looks like it will be a thirsty machine.

Speedy, good to see you on VAF. I am one of Gouda's bud. Nice engine.

G'day Axel

Hi Axel,

Sorry for the tardy reply. Nice hat sighting pic by the way. Next job at hand is the baffling. Luckily the Vans plans and parts are pretty good so going together nicely so far.

Cheers

Nigel