[Diy_efi] vortec engine piston noise?

[Perry Harrington]

I don't know why everyone says forged pistons are noisy.  The OEM pistons
in 5.0 mustangs were forged TRWs.  Ford runs the piston .035 undersized
in the bore.  I rebuilt my motor and got new forged pistons, same ratio.
The damn valves make the most noise.  The new pistons measure 3.995 in
diameter, .030 overbore.  Personally I hate the scam that all the piston
manufacturers are trying to pull on everyone with hypereutectic pistons,
it's a damn farse.  If god intended aluminum to have 18% silicon in it, he
would have made it that way! :)

--Perry

On Wed, May 22, 2002 at 06:20:41PM -0000, Tom Sharpe wrote:
> 
> On Tue, 21 May 2002 23:49:18 -0400, Shannen Durphey <shannen at grolen.com> 
> wrote :
> 
> The short skirt hypereutectic slugs gm used made a ton of noise.
> > 
> Hypereutectic pistons require less clearance because they expand less --- 
> wonder if GM forgot to tighten up the clearances. Last year we rebuilt 
> a '67 L88 427 BBC. You could still see the original hone marks in the 
> cylinders @ 40K miles and get a .016 feeler gauge in the bore with the 
> piston - they don't bend much either. The bore measured about +.010.  I 
> also have an old HP 2 bolt BBC block that measures about the same... and 
> those old forged pistons make a lot of noise until they are properly warmed 
> up....  TomS
> 
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-- 
Perry Harrington             Linux rules all OSes.               APSoft      ()
perry at apsoft dot com 			                 Think Blue. /\

Those who would give up essential liberty to purchase a little temporary safety
deserve neither liberty or safety. Nor, are they likely to end up with either.
                             -- Benjamin Franklin


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