Sorry if the topic title is confusing but I wanted this thread to get some attention . I am having my d16 block bored .020 over to get rid of a bit of a lip that has occured in the cylinder walls for whatever reason which at this point is unclear. So, I am wondering if going .020 over stock is enough to constitute getting .020 over pistons (75.5mm) or just getting .020 oversized rings? I can imagine pros and cons for both applications but I want to know what the pros here think before I get pistons and rings. Thanks guys.

 

that seems like a pretty good questions im no motor guru but to me it seems that due to the piston to cylinder wall clearance is going to be greater and the piston rings would have to be sealing that .5mm more of area than what they are intended to cover because more of the ring would be protruding further away from the piston since the piston is 75mm and the rings are for 75.5 pistons so it seems to me that the rings may prematurely fail. may also run into further ruining your cylinder walls jus due to that greater area of clearance between the piston and the cylinder wall. thats just how i see it i may be wrong.

 

Ask your machine shop for advice, they'll know what to do

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sik96teg &raquo;</TD></TR><TR><TD CLASS="quote">that seems like a pretty good questions im no motor guru but to me it seems that due to the piston to cylinder wall clearance is going to be greater and the piston rings would have to be sealing that .5mm more of area than what they are intended to cover because more of the ring would be protruding further away from the piston since the piston is 75mm and the rings are for 75.5 pistons so it seems to me that the rings may prematurely fail. may also run into further ruining your cylinder walls jus due to that greater area of clearance between the piston and the cylinder wall. thats just how i see it i may be wrong.</TD></TR></TABLE>


Thats kinda how I felt too so I aksed around and talked to some guys who have built some monster engines for some chevys and fords and they all said that anything below .060 over is totaly good with just oversized rings. This may indeed be the case for fords and chevys but hondas may be a different story. I will ask the guys at the speed shop when I pick up the block in a week or so, but in the mean time if anyone has more info shoot it my way. Thanks

 

Still in limbo on this one.......research?

 

You will need the same oversize pistons for the bore size.So a +.020" bore requires a +.020" piston and rings.You should have the pistons before the block is finish honed to get the piston to wall clearance correct.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by NJIN BUILDR &raquo;</TD></TR><TR><TD CLASS="quote">You will need the same oversize pistons for the bore size.So a +.020" bore requires a +.020" piston and rings.You should have the pistons before the block is finish honed to get the piston to wall clearance correct.</TD></TR></TABLE>

Exactly.

Unless you want that motor to come apart in short order, get the pistons and rings. Ignore any advice you have received previously.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jim Truett &raquo;</TD></TR><TR><TD CLASS="quote">

Exactly.

Unless you want that motor to come apart in short order, get the pistons and rings. Ignore any advice you have received previously.</TD></TR></TABLE>

Especially coming from anyone who owns a domestice car/motor.

 

Thanks for the help guys.