Hey guys few questions I need to find out on.... 1. Just spoke to the guys building my bottom end and informed that 6thou / 0.006" had to be removed of the deck of the block, now I need to find out what to piston to deck height is??? Pistons are Wiseco 87.5mm with standard comp, how much will need to be removed of the pistons in order to match up OEM specs on the piston to deck height? Is the VG30DETT a 'zero deck' block? 2. ARP headstuds what torque settings should the head be torqued down to - I know OEM headbolts are 90nm, should headstuds be done up more? If so - what to? Thanks guys!
1/ 2/ Arp bolts torque the same... L19's are more I had a hard time getting a definite answer on where the piston sits in the bore .. Its around zero deck height. My piston sits 8thou out the bore now .. so I wouldn't panic . You have to dummy assemble your engine to see where it sits now
What's the shock on the first one Rob? Matt told me it was simply to bring the deck true again. He also told me it will be dummy assembled to determine where the piston will sit.
Well that's what I was worried about aswell if it would weaken the piston and Matt replied pull a hair out of your head cos thats all that will come off. Also told me that they have taken upto 20thou off pistons when building other motors.
I still dont understand the problem though ?... dummy assemble it and see where it sits first ...I would just leave it where it sits .. its not an issue with a couple of thou out the bore also take any slight raise in comp as a free gift..
Guess I'm worrying before I should, Matt just made it sound very important as to where the piston sits in the bore. How much has been machined of your block Rob?
still have engine numbers showing so not more than 8thou. Matt will be worried about the squish area .. which changes when you deck the block .. you run a thicker head gasket to correct that. http://www.aus300zx.com/forum/showthread.php?t=315072&highlight=piston+height
from what i can understand, they tell you to set the piston 5 thou lower than the deck, with a 1.2mm head gasket, to get that compression value... otherwise check the deck height http://wiseco.com/Catalogs/SportCompact/Nissan.pdf and usually the arp bolt use a little more torque than originals, but you'll find the tension in the box with them
Sorry what's the squish area Rob? I have new OEM headgaskets that I was going to use. Not sure what the thickness is of the OEM gaskets in comparison to gaskets like cometics which vary in thickness.
nice chart Mr Cervus. So 5 thou below looks like where the piston sits in a stock engine.. which calculating it with head gasket thickness makes sense. PM sent Zedboy
