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Old 11-23-2013, 10:49 PM
RichSchmidt RichSchmidt is offline
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Default Re: 62 Corvette Pure Stock Build

Cam within 1% of stock? Is this lift only? Is it at the valve after lash? Any rules on duration,and at what measurements? GM measured their duration off the seat,and gave some whacky numbers,Some factory cams listing over 320 degrees duration. I would look into that.

Heads are the biggie. Are 3 angle valve jobs and back cuts allowed? Are they measuring port volumes(I am assuming measuring chambers). Here are some tricks. When having the valve job done,have the shop open up the already machined area around the intake valve with a larger diameter cutter,and then mill the head back to stock chamber volume. Have the machinist cut the throat out into the bowl with a larger cutter. These areas are already machined,and I would be interested in if there is a spec for them. If you can cut the throat,but they will measure the port volume,you can usually mill material off the intake face of the head and use thicker gaskets to bring the port volume back down. You can have all the trick work done before the valve job,and deck surfacing,and then have the head shot blasted before finishing. Some very slick stocker racers have been known to put their heads in an oven,and get them soft,then take a hard metal pin and roll it back and forth over the pushrod pinch area to move the wall out without grinding.

Of course blueprinting the block with a plate hone job is a good idea. Do they measure piston to head clearance or deck clearance? Can you zero deck the block and restore quench distance with a composition gasket,or do you need to keep the piston down in the hole and run a steel shim like stock? A composition gasket is a trick in itself since you can get one that matches the head,not the bore,and it will give you even a tiny bit more room before airflow meets the bore. I doubt they will allow you to notch the bores.

Is there an allowance for +/- on stroke and rod length. You can resize the rods a bunch to shorten them and then turn the crank down 20 or 30 under with enough offset to get some extra stroke without tipping your hand as far as machined pistons or whacky deck clearances.

How about a lower volume oil pump,and running less oil in the pan? Run a machined down pump (not a stock size pump with a weak spring) to reduce the amount of power needed to turn the pump,and to reduce the amount of oil flying around,and to reduce the amount of oil you need in the pan.

I would think they require stock thickness ring grooves and rings,but can you run a gapless ring,and low tension oil rings?

I figured I would throw these ideas out there.
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