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prostreetC-10 · 07-03-2010, 09:16 AM

It's kind of an odd question. Just why do you want to make it a 409? You're not thinking of the 348/409 chevy "W" series BBC motors are you?

Usually, when you hear of someone running a motor that has a really odd displacement, it's because of the amount of overbore they had to go to remove scratches in the cylinder walls or to true up the overall shape of the cylinder. As bigsnook said, you will usually see .030, .040, 060 and so on. You will bore the cylinders to the size and type of aftermarket pistons you can get. You wouldn't bore a motor to a .038 if you can get pistons to match. Some guys will also bore and stroke to match a rotating kit or to achieve a maximum displacement within a certain block casting for racing or some other reason.

So just why to you want this 409?

07-03-2010, 09:16 AM	#3
prostreetC-10 My Carbon Footprint Join Date: Oct 2008 Location: Orygun Posts: 5,527	Re: changing ci's. It's kind of an odd question. Just why do you want to make it a 409? You're not thinking of the 348/409 chevy "W" series BBC motors are you? Usually, when you hear of someone running a motor that has a really odd displacement, it's because of the amount of overbore they had to go to remove scratches in the cylinder walls or to true up the overall shape of the cylinder. As bigsnook said, you will usually see .030, .040, 060 and so on. You will bore the cylinders to the size and type of aftermarket pistons you can get. You wouldn't bore a motor to a .038 if you can get pistons to match. Some guys will also bore and stroke to match a rotating kit or to achieve a maximum displacement within a certain block casting for racing or some other reason. So just why to you want this 409? __________________ A quick "pedalfest" *Still getting loose (carb test)* 496 Initial fire up video! Last edited by prostreetC-10; 07-03-2010 at 09:17 AM.