Converting a 150hp to 160hp or is it 10:1?

[md11freighter]

Speaking of performance exhaust systems…..I have a leading edge exhaust sitting around if anyone is still wants one. I took mine off chasing high temperatures. My CHT actually went down without it….so it’s not going back on

 

[AZinAK]

Did lycoming make an a2b that was a wide deck?

Yes they did, I have one that is a wide deck and converted to 160 hp making it more or less a B2B.

 

[cubdrvr]

So does the data plate show as an O-320-A2B? O-320-A2B-C? or a -B2B?

 

[farm_boy252]

Can you guys tell me what it takes for a professional to extend the crankcase studs on a narrow deck...does the engine need to come out of the plane, and be completely torn down? Can most aircraft machine shops do it? Thanks for the help

Did you ever go ahead with this?

 

[Cub Builder]

I recently swapped the 8.5:1 pistons in my Wide Deck O-320 for 10:1 pistons from Combustion Technologies. It makes more HP (picked up ~100 RPM), but also appeared to get into detonation on a hot summer day with runaway oil temps. For now, I've dialed the timing back from 25° BTDC to 20° until I have more time to mess with it. Would I make the same decision again? Not sure, but I'm not as enthusiastic as I was before I installed them.

 

[RaisedByWolves]

I recently swapped the 8.5:1 pistons in my Wide Deck O-320 for 10:1 pistons from Combustion Technologies. It makes more HP (picked up ~100 RPM), but also appeared to get into detonation on a hot summer day with runaway oil temps. For now, I've dialed the timing back from 25° BTDC to 20° until I have more time to mess with it. Would I make the same decision again? Not sure, but I'm not as enthusiastic as I was before I installed them.

Makes you wonder, retarding the timing, how much more of that power do you have, you forgot to mention the more fuel flow at cruise too, almost 2gph, oh and wait until you have 200 hrs on the engine, you get to do valves and guides. Im happy going back to 8.5, and hopefully having that reliability back. Sure is nice seeing cht’s below 400 and a lower oil temp.

 

[cubdrvr]

An O-360 has the same bore diameter but has a different case, camshaft, crankshaft, sump, and carb. The 320-360 conversion is called an engine swap

If you want an 180hp 0-340 like the carbon cubs have with the electronic ignition you need the ECI stroker 0-340 crankshaft kit which is for the 0-320 series engines.

Jason

My experience is that the O-320 and O-360 cases are identical. Only the idler shafts/bolts are different.

 

[KevinJ]

I recently swapped the 8.5:1 pistons in my Wide Deck O-320 for 10:1 pistons from Combustion Technologies. It makes more HP (picked up ~100 RPM), but also appeared to get into detonation on a hot summer day with runaway oil temps. For now, I've dialed the timing back from 25° BTDC to 20° until I have more time to mess with it. Would I make the same decision again? Not sure, but I'm not as enthusiastic as I was before I installed them.

What elevation are you based at out of curiosity?

 

[Dog]

I recently swapped the 8.5:1 pistons in my Wide Deck O-320 for 10:1 pistons from Combustion Technologies. It makes more HP (picked up ~100 RPM), but also appeared to get into detonation on a hot summer day with runaway oil temps. For now, I've dialed the timing back from 25° BTDC to 20° until I have more time to mess with it. Would I make the same decision again? Not sure, but I'm not as enthusiastic as I was before I installed them.

Yes definitely need bigger main jets if you bump compression especially at low level. That is to be expected.

The greatest benefit are seen at high elevation I would not mess with it if you mostly fly down sea level stuff.

Pulling timing helps against detonation but hurts performance — what you need is more fuel.

 

[gntw]

I work on a smith cub with a 10to1 comp lycon built 0320 done 20 years ago was not put in service until 10 years ago had lazer ignition came with no carb.put a 5217 carb on a universal airbox built by Larry bower .engine ran ok was real easy on fuel. 2 years ago install a areosport 340 carb recommended by them made no difference.we both have 180 with pponk 520 had carb issues . Got that fixed had a new ex 10 -5284 carb done for 520 . Changed throttle arm installed that carb on the universal airbox and put it on the 320 .took about 2 hrs ran it same day.pickup up75 rpm static 100 rpm level flight . In cruise leaned almost the same .better fuel burn then my stock 180 cub .he is running a 82-44 prop. Now has duel p mags

 

[Cub Builder]

What elevation are you based at out of curiosity?

700'.

 

[RaisedByWolves]

Yes definitely need bigger main jets if you bump compression especially at low level. That is to be expected.

The greatest benefit are seen at high elevation I would not mess with it if you mostly fly down sea level stuff.

Pulling timing helps against detonation but hurts performance — what you need is more fuel.

16gph on takeoff on a 320. Could keep temps reasonable in cruise but it was 10.5Gph

 

[gntw]

Based at 2000 some time density altitude near sea level in winter. Definitely makes more power