new hypers or used forged?

grumpyvette

Administrator
Staff member
"hey grumpy, Ive got an engine Im building and a choice to make, I,m Building a street sbc 400. Came across a guy who is selling a set of good looking SRP pistons for the same price I can get a set of new KB's hypereutectics.
What would be the better way to go on a street engine, if they will cost the same price +/- $50.00
Do forged pistons wear the bores faster? Seems like I heard something about forged rock in the bores when cold??
Any other information I would need to know to make the best decision?
Thanks."

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http://www.tooltopia.com/fowler-72-646-300.aspx



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Id suggest taking the pistons to your local machine shop and asking your machinist to look them over , measure them,and if he can use them in your particular application,well, if he can, then buy the pistons in a heart beat, if not PASS on the deal.
If your friend wants to sell the pistons he should not object,
FORGED PISTONS NEED A BIT MORE BORE CLEARANCE BECAUSE THEY EXPAND A BIT MORE AS THEY REACH OPERATIONAL TEMPS THAN HYPEREUTECTICS.
if the forged pistons will exactly fit your bore, or are a bit larger and you intend to bore and hone your block to the exact size required, and look to be in excellent condition ID buy them.
BUT all PISTONS ARE used ONCE INSTALLED AND THE ENGINES BEEN STARTED , JUST KEEP IN MIND YOU NEED TO HAVE THE PISTON BORES MATCH THE PISTON BEING USED AND ITS REQUIRED EXPANSION CHARACTERISTICS.


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