Welcome new member Jocke. Below is his introductory message.
No problem on making more power with your Poly. You have first to decide how much horsepower you want the engine to produce and balance that off against street-ability. Yes, there is no need to swap to a BB to get plenty of power with the engine you have.
Gary H.
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Hello. I'm A Swedish guy with a -65 fury III conv. And of course it has a
poly 318 inside but it wouldn't hurt with a little more power😀 and I
don't like to change it to a BB
/ Jocke