mrgwrnch

I have a question about a 2002 LS1 engine I'm overhauling for my daily driven '64 Nova. I purchased Mahle LS1314905F04 pistons that are designed for a finished bore size of 3.905" (this varies with application such as type of power adder). My machine shop decided to power hone the bores to 3.9065". The pistons measure approximately 3.902" depending on the temperature. I called Mahle's technical line, they said that was to large, but also said it would run fine. They also said that the engine would be noisey. My question is, who has experienced this and what was your thoughts on this? How noisey will this be?

Thanks in advance.

bww3588

iTrader: (49)

.0045 is .00225 piston to wall. You should be fine.

mrgwrnch

Thanks for the reply. I understand how you came to the conclusion of .0025", is that how piston to wall clearance is calculated (divided by 2) or is the total sum the industry standard?

mrgwrnch

Sorry, meant to say .00225"

Sales4@Texas-Speed

iTrader: (4)

I bet the piston slap in this motor will be the noise they were referring to. That is getting on the large side of piston to bore clearance, but as Mahle said it should run fine. The extra piston to bore will allow the piston to rock just slightly more causing the extra noise.

mrgwrnch

As a side note, when I spoke John @ Mahle, he was kind enough to swap out my untouched pistons for yhe next oversize at no charge. Now they have a customer for life.

PREDATOR-Z

Props to Mahle

Sales4@Texas-Speed

iTrader: (4)

No kidding, great customer service on that one.

JPH

iTrader: (2)

The extra ptw clearance will also help the bore from wanting to tear the skirt coating off the piston if your tune is not up to par.