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Compression ratio VS my other parts?? and prop?

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pigpenracing

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Ok guys,
Thanks for all the helpful comments on my engine rebuild.
I am not 100% set in stone about compression ratio yet. The new cylinders come with stock 8.5:1 but my supplier will buy the pistons back if I go high compression.
The Eagle was really awesome with the 11:1 motor until it broke. This thing at 25/25 would cruise 210 plus mph on my gps! Really damn impressive for a biplane. At 21" mainfold and 2400 rpm it showed 175-180 mph lean of peak on 11gph.
Nobody believes these numbers but it did really haul the mail. I had to put my buddy up front with a gps for him to believe it.
That is why I want to stay with higher compression. I am scared if I go back stock it will be a regular ol slow biplane again. But on the other hand I want relibility. I don't fly competitions , just fly for fun. It did burn 28GPH at acro setting though, thats a downfall. Had to pour the fuel to keep cht's cool.

The motor had 11:1's
front mount rsa 10 fuel servo-cold air intake
6 into 1 exhaust
3 blade BIG M/T with the 203 wide chord blades. Its bigger than the S-2B M/T's

I know the prop and the big fuel servo worked hand in hand with the high compression and HP. Now what happens if I put stock 8.5:1?
Will the fuel servo and prop be to big for the low HP and in return be a dog?
Thats why I am really leaning to 10:1.

Where would I see any difference between the compressions? Wide open only? Or will it effect the power all power settings?

I know if I build a 14:1 compression Big chevy and run a 1050 carb it is all good. If I run that 1050 carb with 8:1 compression it is a total dog.
I am sure the Lycoming is the same way correct?
Thanks guys!
 

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