Pistons.

[Mike Tuckwood]

OK, as a follow on from a previous thread, for those of you who are interested, and believe me, you do have to be interested to get all the way out to the other side of this stuff.
Here are a couple of links where the differences between pistons have been covered in quite some depth. Just to show that pistons aren't as "simple" as you may think?

WARNING..... HIGH GEEK CONTENT WITHIN.

http://forums.nasioc.com/forums/showthread.php?t=9...

This one gets little heavier http://forums.nasioc.com/forums/showthread.php?t=1...

Still very interesting though and covers many of the points we need to consider whenm someone is asking us to build an engine for them.



Mike.

[andygtt]

but it doesnt answer the question "will my forged piston take a zillion BHP?"

[R0162]

So which pistons would be your choice Mike?

Edited by R0162 on Tuesday 21st September 15:36

[TuxMan]

So Mike if you change to forged pistons do you have to hone the bores for more clearence , I have been told YES but if the pistons expand at the same rate then it should not be needed !!

[Mike Tuckwood]

TuxMan said:

So Mike if you change to forged pistons do you have to hone the bores for more clearence , I have been told YES but if the pistons expand at the same rate then it should not be needed !!

There's a whole lot more to it than just putting a named product piston in there Simon.
Acceptable Piston to bore clearance levels are only part of the picture really. Most manufacturers will specify a preferred clearance, but then they don't know exactly what you're going to subject the car to?

Ideally you would bore or hione to piston as we do when we build an engine so that the exact tolerance is in place for each cylinder.

Mike

[mgbond]

I'm using direct forged replacements for the 2.5 and I have two choices. Buy them from Noble Motorsport or get mine coppied.

If I go the make route then this is what I'm being told:
Asking about I have been told not to go for Horizontal gas holes as this can where the ring quicker.

I have also been told to go for contact reduction grooves (i think helps againt det) and accumulator grooves.

Also can have the Pistons hardened making the skirts stronger and the crown ceramic coated to reduce retained heat?

What do you think?

Bondy