silvadful
Well-Known Member
hey guys. i have a 318 bored 20 over kb 399 pistons. block been bored, honed an it time to mock up an see where pistons sit. what is the method to do this an what tools u need? thanx for help in ++
Best method of zero decking a block is to use the tallest 4 piston and rod assembly,one on each corner and then measure down to the piston from the deck at TDC,marking on the deck the measurement and do each corner.Once you have found the amount,you can tell the machine shop what needs to come off from each end.This is with the assumption that your piston/rod assembly not been blue printed.You need a depth mic and need to measure to the higest point of the pistons rocking the pistons to see if there is any change in the readings,on all 4 corners,MMT
not sure what u mean by tallest.shouldnt they be the same ?
I looked on the Summit site and it said "-6.20cc", although it DOES have a dome to it. It looks like the small perimeter of that piston top is the flat area, so that where I'd measure.
http://www.summitracing.com/parts/uem-kb399-030
The crank throws can be off,rod length can be shorter or longer,piston pin to crown can be shorter or taller than others.Unless all the rotating assembly has been blue printed,you could have a short and long rod installed and screw up the deck clearance,as the 2 other rods MIGHT be taller and then you have +deck height.Connsistancy is the key to decking a block,and making every assembly the same,in length and weight.If you do not do this,you roll the dice on what happens.Mrmopartech