so how come the pistons at tdc aren't flat along the block deck
12-09-2017, 07:38 PM
#1
so how come the pistons at tdc aren't flat along the block deck stupid question, i have my heads off and brought them all to the top one by one to clean off the carbon. i noticed when the pistons are tdc, the bottom of the piston (header side) would be flush or even with the block. but the top (intake side) would be slightly above the deck. so it would seem as if the pistons are kind of cocked or crooked inside the cylinders. why is this?
12-09-2017, 08:01 PM
#2
Piston to wall clearance is what allows the rocking on directional change
LS engine’s typically have positive deck (pistons sticking out)
Bringing the primary ring higher reduces dead quench lessens emissions and improves brake specific fuel consumption (efficiency)
LS engine’s typically have positive deck (pistons sticking out)
Bringing the primary ring higher reduces dead quench lessens emissions and improves brake specific fuel consumption (efficiency)
12-09-2017, 09:00 PM
#4
ModSquad
iTrader: (6)
Great answer A.R.!
Not to mention that the LS series engines have offset piston pins, meaning that the pin isn’t exactly in the center of the piston. This exagerates the rocking that your seeing Floorman.
Not to mention that the LS series engines have offset piston pins, meaning that the pin isn’t exactly in the center of the piston. This exagerates the rocking that your seeing Floorman.
12-09-2017, 09:32 PM
#5
stupid question, i have my heads off and brought them all to the top one by one to clean off the carbon. i noticed when the pistons are tdc, the bottom of the piston (header side) would be flush or even with the block. but the top (intake side) would be slightly above the deck. so it would seem as if the pistons are kind of cocked or crooked inside the cylinders. why is this?
12-10-2017, 10:40 AM
#7
FormerVendor
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Pin Offset = Boost Safety Hi Velle, Your answer ALSO, the Pin Offset. (good tech)
I fit RaceTec pistons with "offset pins" if the customer will allow the small cost increase.
SO I ask, why is the pin offset (OEM Side) IMPORTANT on a S/C engine ?
Lance
I fit RaceTec pistons with "offset pins" if the customer will allow the small cost increase.
SO I ask, why is the pin offset (OEM Side) IMPORTANT on a S/C engine ?
Lance
