Quote:
Originally posted by Ron1
I also qualified what I said by saying, IF your budget can afford it.
You have some data on this slapping & fluttering I can read?
I'm sure we would all like to read up on it..
Ron
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And i qualified what i said by saying it was my 2 cents worth
As for the slapping ... sometimes you barely notice it sometimes the motor sounds like a bucket of rocks until it warms up ... thats been common knowledge since they started using forgings for pistons. You have to run them significantly looser because they expand significantly more when they heat up, so when they're still cold they're loose as a goose and they rock (skirts slap) in the bore.
http://www.kb-silvolite.com/page11.htm
heres a tid bit from glm-marine.com
"An example of the dramatic expansion of forged pistons is the piston skirt clearances in the cylinder. A typical cast piston has a skirt clearance of approximately .0007 to .0009. A forged piston has a skirt clearance of .005 to .007. The forged piston has 10 times more slop in the cylinder. This results in less ring stability against the cylinderical wall, more piston noise and extra blowby."
Now i'll make the same challenge to you that you made to me ... show me some data that says high performance hyperutectic pistons are no good. I know people make that statement all the time but i think for the most part they're just saying it because they heard someone else say it, and that don't make it so ... The mfgs say they are fine up to about 100 HP shot of N2O or mild to med turbo or supercharger use. I've seen no hard data that proves that statement wrong. If you have some i'd truely like to see it.
One more for the road ...note the pistons used under specifications for 2001 section, and this is a 10 sec car
http://www.toohighpsi.com/DadTT/dadTT.htm