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Old 09-21-2018, 04:44 PM
NewbRVator NewbRVator is offline
Join Date: Jul 2018
Location: CA
Posts: 79
Default Top rebuild 0-360

When I do a top end on a carburated 0-360 Lycoming w/ 8.5:1 pistons is there any benefit to changing the pistons to higher compression like 9:1 if I want marginally more power especially above 10k feet.

Why are is the O-360 Lycoming redline set at 2700? What could I do to safely increase the redline to 2800? Would that entail a complete rebuild and not just a top end?

I would imagine balancing and blueing would achieve a higher redline?

The reason I ask is the engine hp curve reveals a lot of hp at 2700 and I imagine there are 20hp more at 2800 with higher compression 9:1 pistons.

Then of course I would need a different prop.

Lots of questions any one got an idea to share?

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Old 09-21-2018, 09:11 PM
Tommy123 Tommy123 is offline
Join Date: Jul 2018
Location: Naples fl
Posts: 140
Default 360

Racers spend tons of money and engineering spinning engines beyond redline. Easier and cheaper getting a io. A lot of work for 20hp. It ain’t a Chevy engine.
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Old 09-22-2018, 07:05 AM
Mel's Avatar
Mel Mel is offline
Join Date: Mar 2005
Location: Dallas area
Posts: 10,306

Also keep in mind that HP has little to do with speed in an airplane. For take-off and climb, yes. But for speed, it takes a ton of HP increase to result in very little speed increase.

As far as the 2700 redline; a lot of that is because Lycoming has a very loose tolerance on balance. If you are going to regularly run above 2700, you should pay particular attention to balance. Other than that, many Lycomings are regularly run at 2800, 2900, 3000 rpm and more. Yes, it will shorten TBO, but not by as much as you might think.
Mel Asberry..DAR since last century
A&P/EAA (LifeTime) Tech Counselor/Flight Advisor/Nat'l Test Pilot School
Specializing in Amateur-Built and Light-Sport Aircraft
North Texas (8TA5)
RV-6 Flying since 1993, 172hp O-320, 3-Blade Catto (since 2003)Sold
Legend Cub purchased 12/2017
FRIEND of the RV-1
Eagle's Nest Mentor
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Last edited by Mel : 09-22-2018 at 10:56 AM.
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Old 09-22-2018, 07:44 AM
Robert Anglin Robert Anglin is offline
Join Date: Mar 2008
Location: houston, texas
Posts: 900
Default Agreed.

Mel is right on the money here. Blue printing an engine is just an old saying that is seldom done now a day unless you custom build a power plant. The time and money that go's into an engine to get more out of a factory stock power plant is mostly weight savings and balance of the O.E.M. parts. Either by changing them out or reworking the O.E.M. component. A lot of this you can learn and do yourself with a little help from a good engine shop. Most of the good ones are into a little racing from time to time. We run a stock IO-360 that makes about 195 Hp. There is only one component that is not P.M.A. Lycon., the cylinders. We knew at the time that E.C.I. had a head that had valve seats and guides that allowed for better air flow than stock and that the cylinder barrels were a little lighter with tapered fins. The rest of the engine was simply hand worked to be very well balanced and matched, with a little port work. You can do all this at home in the garage. With a little attention to detail, turning 29-3,000 with a good prop is not that big a deal for these engines. Most of these engines are slightly de-rated for safety and longevity anyway. I would respect the factory recommendations if I had a stock engine and wanted to protect my warranty, however.
This is not a 140 cu. in. Couswarths we are trying to get 5-600 Hp. out of for 5 or 6 hours. Just some thoughts on the subject. Yours, R.E.A. III # 80888

Last edited by Robert Anglin : 09-23-2018 at 08:52 AM.
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Old 09-22-2018, 10:21 AM
jrs14855 jrs14855 is offline
Join Date: Apr 2008
Location: Lake Havasu City AZ
Posts: 2,222
Default 0 360

1000 hours plus in a Pitts with 0 360 A4A running at 3300-3500 rpm almost every flight. Still running perfectly at 1000 hours. Aerobatic TBO at the time was 1400 hours.
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