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Lycon engine work

M5fly

Well Known Member
I'm looking into getting Lycon to port and polish the heads on my O-320 and possibly upgrade to higher compression pistons. The engine is the 150hp E2A, which IIRC there was a thread on here that mentioned higher compression pistons not being a good option on the E series engines, any truth to this? Lycon's two main options are 8.5:1 factory pistons or their own 10:1 NFS pistons, which is their recommendation. Will doing a nitride lining make this a viable option? My main reason for wanting to do these upgrades is in search of better climb performance at high DA at a relatively cheap cost.
 
Engine

The 160 hp pistons are not an issue on any E series. Some of the E series have 0 235 front main bearing.
the 0 235 front main bearing will not support a constant speed prop.
I have 10-1 pitons in my 0 320, balanced but otherwise stock. Something to keep in mind is the future of 100LL fuel. Stock 160 hp pistons will work fine on mid grade auto fuel.
 
I have been overhauling air cooled engines for over 40 years. Mostly Porsche.
I have found that better performance at a cheap cost does not exist. Also upping performance of a stock engine leads to much less engine life. Since you are dealing with Lycon I would listen to what Kenny and his crew recommend. 10-1 is high

Moving J3 to another hangar tomorrow to put 3B in our hangar for final assembly
At KCVH
 
I agree, the 10:1 pistons do seem a little high and I'm not sure it's worth the risk. It seems going with 8.5:1 and flowing the heads would be a significant power upgrade without decreasing reliability. Even 10hp would make a huge difference in climb performance at the high DA's we get in the summer.
 
engine work

My primary source of information was the late great Monty Barrett. With 10-1 pistons if you run the engine the way the serious aerobatic people do you will start to see a decrease in oil pressure at around 7-800 hours. This is due to wear on the connecting rod bearings. Total failures of the hot rod engines is extremely rare unless you are talking Reno race engines which are an entirely different situation. I know of Reno engines that have used compression as high as 13-1.
I am very skeptical about ANY power increase from port work. One of the issues with the Lycon port work is that they MAY weaken the cylinder by removing too much metal.
10-1 pistons are widely used and airplanes are not falling out of the sky because of this.
I treat the 10-1 pistons in my 0 320 as a "poor mans supercharger". At 500' agl I reduce power to 24" and maintain that in the climb. For cruise the pistons will allow 75% power at a significantly higher altitude than stock 160 hp pistons. I expect my engine to last well beyond my personal "use by date"
 
I have wondered about higher compression ratios at higher altitude. The altitude is reducing the amount of air available to compress.

For example, a fictitious engine's cylinder might take in 3 oz of air at sea-level. By 10,000', that cylinder is only taking 2oz of air. The amount of air being compressed is lower, the forces inside the cylinder and on the remaining engine components (rods, bearings, crank). My wild uneducated hypothesis is that a 10:1 engine WOT at 10,000' is under similar stress to a 7:1 engine operating WOT at a lower altitude, arbitrary picking 7000'.

The aerobatic engines with 10:1 pistons are also seeing dramatically increased gyroscopic loads and spend much more of their lives at high power as compared to an RV engine that typically lives 75% power and below.

I suppose the point of my whole post and theory is that an engine that spends its life at 6000' field elevation with 10:1 pistons is stressing and wearing the engine in a similar manner to a 7:1 engine living at 3500' field elevation.

Now we wait for an engine guru to tell me I'm wrong. :D
 
There are the pistons from the H2AD 320 that are 9:1 and combustech.com has all flavors and 9.5:1. If you don't want to go to 10:1 you have options.
 
I have wondered about higher compression ratios at higher altitude. The altitude is reducing the amount of air available to compress.

For example, a fictitious engine's cylinder might take in 3 oz of air at sea-level. By 10,000', that cylinder is only taking 2oz of air. The amount of air being compressed is lower, the forces inside the cylinder and on the remaining engine components (rods, bearings, crank). My wild uneducated hypothesis is that a 10:1 engine WOT at 10,000' is under similar stress to a 7:1 engine operating WOT at a lower altitude, arbitrary picking 7000'.

The aerobatic engines with 10:1 pistons are also seeing dramatically increased gyroscopic loads and spend much more of their lives at high power as compared to an RV engine that typically lives 75% power and below.

I suppose the point of my whole post and theory is that an engine that spends its life at 6000' field elevation with 10:1 pistons is stressing and wearing the engine in a similar manner to a 7:1 engine living at 3500' field elevation.

Now we wait for an engine guru to tell me I'm wrong. :D

I like the idea behind that! Lol I'd also be interested in hearing what the gurus have to say about it.

I've begun to hear the horror stories of Lycon having your engine for 8+ months while completing the work, that might also make me pump the brakes or look for alternatives. I can't be grounded that long!
 
Engine

I failed to notice you are based at Reno. If 90% of your flying is in the high country or the hot desert you will benefit from the 10-1 pistons and any extra wear will simple be caused by the occasional sea level operation.
Sea level for me in the hot months is typically 4-6000' density altitude.
I personally would not bother with the port work. The port work is best for engines that operate at much higher r/p.
Pacific Continental at Whiteman Airport is reported to do good work. Harrison in IN also has a good reputation. Your E series cylinders are probably plain steel unless the cylinders have been changed. Have the cylinders ground .010 over for a bit more performance
 
LyCon turned my 540 around in 3 months - including the porting and case O ring mod. And more than half of that time was simply waiting for it to make its way to the head of the line. Once wrenches started turning, it was a matter of weeks before it was running on the dyno.
 
LyCon turned my 540 around in 3 months - including the porting and case O ring mod. And more than half of that time was simply waiting for it to make its way to the head of the line. Once wrenches started turning, it was a matter of weeks before it was running on the dyno.

That's great to hear, I would hope what I'm looking for would follow a similar timeline. I can probably deal with 3 months, just not 6+.
 
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