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Possum Bluff
plca10b-
Anky_Gator_Season_2007
KRVSA_SA_031
abby checking ou her new home
Loughmans Lodge Big Gator shoot out 2014
A

Anonymous

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I don't recognize the rocker covers on this motor. What is it?
Looks boss with the Roots on top :twisted:

Lake_081.jpg
 
It's a continental 360 or 3 something i think I've seen that engine before but I'm not an air craft guy so I could be wrong
 
Oh, drool!

Dry sump, twin turbo. Bet that will turn a fatty prop!

I see the script on the covers there, but what size? 520?
 
It's a GPU with 520 downdraft intake cylinders on it commonly called gtsio cylinders. These cylinders were used on some turbocharged 520's and gear reducted turbo 520's. They are often installed on GPU's because the intake stays on top of the motor like the stock GPU intake.

Larry
 
I know the guy who owns that boat.. Its a GPU case with gistu 0-520 cylinders, turbo-charged, He most of the time put that set of metal work on a predator hull, but often switches over to a step hull for the races..
 
Once again Cracker you have enlightened me good tech article I’m not an aircraft guy but I argue bore and stroke and cubic inch numbers with a lot of aircraft guy’s and they are way off on the cubic inch sizes they claim on their stroker motors. Just as I knew a ¼ more stroke only adds 30 cubic inches to a 550 so the math I use tells me a 1/8 stroke adds 15 cubic inches but when you offset grind a crank if you use a standard crank your lucky to gain a .100 stroke so you only gain 9 cubic inches. So more math here if an O540 makes 320HP that motor makes .59HP per cubic inch so you gained a whopping 5.3 horsepower by stroking your crank taking out your hardened and nitrided surface and removing the radius from your rod journals in other words you just turned your crank into a weak POS for 5.3 horsepower. The big inch aircraft guy’s are ruining motors for 5.3 horsepower that’s crazy especially when there is 200 way’s to make much more power without weakening the motor.
 
Thunder,

What do you suppose that gpu with the gtsio 520 cylinders and the big supercharger weighs? I love the innovation though.

Jim
 
Thunder,

The bore and stroke for a 540 is 5.125 and 4.375. That calculates out to 541 cu in. A .1 stroke increase would produce 554 cu in if my calculations are right.

Jim
 
You are correct I came up with 553.89 cubic inches. Now just think that’s 4 cubic inches or 2.3 more horsepower. All you have to do is remove the hardened nitrated layer from your crank take away material at the most crucial point and remove the radius from your journal. Oh ya and buy those expensive small journal rods that are 50 years old. If I told a car motor guy that I would turn his 350 Small block Chevy into a 354 and make him 2.3 more horse power for $2,500 he would laugh at me.
 
Thunder,

I think I have told you about my son's 540 in his show plane. It uses a Lycoming crank and cam. It will hover the Pitts special with 15 mph wind. They don't come much more trick than that one.



Jim
 
Waterthunder":1n8nqt9z said:
You are If I told a car motor guy that I would turn his 350 Small block Chevy into a 354 and make him 2.3 more horse power for $2,500 he would laugh at me.
Click to expand...

LMAO :lol:
 
Lycoming did build a few angle valve 580's a few years ago. They made it into some of the aerobatic monoplanes. I don't know anything about them except they exist.

Jim
 
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