ive got a n42 L6 and I was playing around with the "L series engine builder software", trying to up the compression in my otherwise standard motor.

It says that flattop pistons will give 9.82:1..which is good BUT the z car garage web site says flattops would give 10.4:1..

which one is right??

Then I tried putting a ld28 crank into my standard n42 motor and L series engine builder said id get 10.4:1 !!! perfect...BUT it says that my deck height is ok..wouldnt the pistons be sticking above the block with a stroker crank with no different rods/pistons?

Any ideas? Whos right?

oh... deck is how much the piston goes above the block...

I thought that it meant it went above when the number was negative..Is 2.030 mm too much deck,,ie will it hit the head?

You can't just put the LD28 crank in without changing rods and pistons. The pin height of the L28 pistons is too low, yeilding too tall a deck height. You need to use L24 rods, and KA24 pistons (240SX). And then you need to mill the top of the KA24 pistons to give an acceptable deck height . Press the L31 button and you will see what I mean. The deck height should be close to zero. A stock L28 has a deck height of + 0.03mm. If you keep the deck height close to stock, you won't have interference problems.

Pete