.30 over/stock pistons
06-13-2009, 09:56 PM
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.30 over/stock pistons
Someone recently told me that stock pistons can be used in a 350 that has been bored .30 over as long as over sized rings are used. I dont quite know what to think of this. I always thought that over sized pistons were needed. Anyone have any insight into this?
06-13-2009, 10:43 PM
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Re: .30 over/stock pistons
You'll have to measure the pistons to see if they're larger than stock. If they're a stock type replacement piston for an overbore, there should be a .030" stamped on them somewhere. You can't use standard bore pistons in an overbored cylinder. There's always a specific piston to wall clearance specification when installing pistons.
I think you can clean up the cylinders to around .010" over and still use factory pistons with oversized rings but that may even be too much.
I think you can clean up the cylinders to around .010" over and still use factory pistons with oversized rings but that may even be too much.
Last edited by AlkyIROC; 06-13-2009 at 10:59 PM.
06-13-2009, 10:44 PM
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Re: .30 over/stock pistons
Someone gave you incorrect information,period.
06-14-2009, 06:55 PM
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Re: .30 over/stock pistons
You might could run stock pistons on a .010 over bored engine, I've ran a Briggs & Stratton lawnmower like that for years, it just rattles a little, but .030 would be out of the question, however if you bore the engine .30 over you wont have any cylinder walls left!!!
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