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burgo
30-03-07, 03:08 AM
right im building an x16xe for my new nova and ive got a set of brand new pistons sitting here for it. the thing is im getting mild cams for it for now but later on i am going to go more lairy with it and therefore will need the pistons pocketing, so i may aswell do it now. the thing i need to know is how much should i have them done by?
Stuart
30-03-07, 08:24 AM
about 2mm iirc
stv-b16a
30-03-07, 10:09 AM
i just realised you have been posting on this site for nearly 37 years stuart!!! lol when did they start production on the nova? lol
Lee
30-03-07, 10:14 AM
i just realised you have been posting on this site for nearly 37 years stuart!!! lol when did they start production on the nova? lol

That was a glitch when the forum software changed, people who were registered before a certain date have a 1970 join date.
stv-b16a
30-03-07, 10:26 AM
lol lol
Stuart
30-03-07, 10:43 AM
its a glitch in the matrix...
iirc the chevvy nova was in production in the 70's lol
stv-b16a
30-03-07, 10:52 AM
yes. fair play,they were indeed. lol.

when pocketing pistons,do you go for one single depresion across the top of the piston or say two or four individual recesses for the valves? how does this affect compression and combustion dynamics.
Adam
30-03-07, 10:54 AM
Individual recesses.
Jon_nova1
30-03-07, 10:56 AM
http://www.sbdev.co.uk/Pistons/Piston%20photos/PIST-OM77.90XS%20a.gif

from what i've been told, as im getting mine done, it doesn't affect compression very much and combustion is pretty much the same

oh by the way those pistons are for 16V so have room for 4 valves per cylinder ;)
Stuart
30-03-07, 11:01 AM
the 16v engines have 4 pockets already for the valve, but they need to be deeper for higher TDC lift cams, this is obtained by incresing the dpeth of the cutouts purprendicular to the existing cutout. Bear in mind ther eisnt a huge ammount of meat in the pistons there.

CR and burn shouldnt be effectted.
stv-b16a
30-03-07, 11:06 AM
great. cheers lads.

i once saw this dirty great piston from some form of marine motor. it had a pocket in it you could fit your fist into. lol
burgo
30-03-07, 05:43 PM
thank you please mr stu
RobMarriott
30-03-07, 06:20 PM
What sort of 'lairy' cams will you be going for?
And what sort of 'mild' for that matter? lol
Adam
30-03-07, 06:26 PM
Mild is something like Kents 244s.

Lairy i'd say is anything above the 270 mark(264 being max on std pistons iirc)