I've heard rumors that you can purchase such, but anytime I've shopped for stock bore pistons I haven't seen any...

I always thought this was due to the fact that forged pistons need a greater piston to wall clearance and different spec for ring gaps.....

So... are these "stock bore" forged pistons actually slightly less and designed for such?

Anyone?

 

You can buy stock bore pistons from pretty much anyone. Arias, JE, Wiseco, etc... The main reason why you want to go with a slightly oversized piston is to clean up the cylinder walls.

 

We stock stock bore and oversize pistons on the shelf.

 

Ben, kind of a trick question. I think what he is asking for is a forged piston that is exactly 81mm in diameter. Most aftermarket pistons are about .0035" smaller than 81mm diameter. He wants to put a forged piston in an OEM bore and get the right piston to wall clearance. Do you have a piston like that available?
The second problem with doing that is the stock sleeves can be oval, balooned out or tapered and really need a bore to 81.5mm.
Kind of like taking a shower and then putting your dirty underware back on.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl &raquo;</TD></TR><TR><TD CLASS="quote">Kind of like taking a shower and then putting your dirty underware back on. </TD></TR></TABLE>

You mean everyone doesn't do this? I guess I gotta go back to the Days of the week underwear!!


But seriously unless the motor is brand new it is best to go ahead and do it correctly overbore to 81.5mm and a nice hone job. All piston companies have the 81mm bore available from what I have seen.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl &raquo;</TD></TR><TR><TD CLASS="quote">Ben, kind of a trick question. I think what he is asking for is a forged piston that is exactly 81mm in diameter. Most aftermarket pistons are about .0035" smaller than 81mm diameter. He wants to put a forged piston in an OEM bore and get the right piston to wall clearance. Do you have a piston like that available?
The second problem with doing that is the stock sleeves can be oval, balooned out or tapered and really need a bore to 81.5mm.
Kind of like taking a shower and then putting your dirty underware back on. </TD></TR></TABLE>


THANK YOU EARL.

It's a nearly new block. The hone is still good and I'd be willing to take the risk on going without an overbore - simple rehone would do it for me if even that is needed... but the right piston to wall clearance IS most important to me.

 

I have found the SRP pistons have a little tighter clearance and might work well for stock bore.A rep from JE told me they have a differant silicone content and have less expansion.
But you are better off going over size and making sure the bores are 100% right of you can.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRVRX &raquo;</TD></TR><TR><TD CLASS="quote">I have found the SRP pistons have a little tighter clearance and might work well for stock bore.A rep from JE told me they have a differant silicone content and have less expansion.
But you are better off going over size and making sure the bores are 100% right of you can.</TD></TR></TABLE>


Well this is just for reference, but I was wondering why not on a low mileage block where the hone is still good... heck it's a little easier just pulling the head and replacing pistons and rods, bearings, and butting her back up while leaving the shortblock still in the engine bay. It could be done in a weekend in your garage by yourself with maybe a buddy to help.

I'm surprised there aren't some runs of stock bore forged pistons that'll spec out on a stock new oem block or low mileage one.....

I suppose I could take a set of forged pistons to the machine shop and have them shaved down a hair.....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Black R &raquo;</TD></TR><TR><TD CLASS="quote"> I suppose I could take a set of forged pistons to the machine shop and have them shaved down a hair..... </TD></TR></TABLE>Not in your wildest dreams could you do that. But even if you could, it's going the wrong direction.

 

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


Well this is just for reference, but I was wondering why not on a low mileage block where the hone is still good... heck it's a little easier just pulling the head and replacing pistons and rods, bearings, and butting her back up while leaving the shortblock still in the engine bay. It could be done in a weekend in your garage by yourself with maybe a buddy to help.
</TD></TR></TABLE>If you are already in there...with the head and block apart, why not just replace the pistons, rods, bearings, etc. I am pretty sure you don't want to do this tidious work again next time. Who knows... your pistons may crack next week and then you will have to do it all over again. No point there.