Head swap
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Head swap
Well I started doing my own research into my pinging problem and discovered that my compression is actually around 12.1:1
With my the pistons and extra stroke i have i figured it would have been 11.3:1
Well after calling the piston company it turns out my piston is .005 above the deck which shot my compression through the roof! At .015 the piston is flush with the deck, but my machine shop told me it was at .010 so they decked it to that. So I will be putting on a set of 76cc heads to bring her down to about 9.75:1. Honestly with the stroke and cam I have now im not worried if it has less compression than it did stock.. It will run the same if not better because it wont PING!
My question is should i order a gasket set for an 86 corvette or for a 90 corvette? The main difference is valve cover gaskets it looks like.
Hope to get this done soon as well. Car is WAYYY too hard to drive since i cant go over half throttle without ping..
P.S. sorry for the long winded posts I have been gone a while and trying to get everything down.
With my the pistons and extra stroke i have i figured it would have been 11.3:1
Well after calling the piston company it turns out my piston is .005 above the deck which shot my compression through the roof! At .015 the piston is flush with the deck, but my machine shop told me it was at .010 so they decked it to that. So I will be putting on a set of 76cc heads to bring her down to about 9.75:1. Honestly with the stroke and cam I have now im not worried if it has less compression than it did stock.. It will run the same if not better because it wont PING!
My question is should i order a gasket set for an 86 corvette or for a 90 corvette? The main difference is valve cover gaskets it looks like.
Hope to get this done soon as well. Car is WAYYY too hard to drive since i cant go over half throttle without ping..
P.S. sorry for the long winded posts I have been gone a while and trying to get everything down.
Last edited by 76z28; Dec 3, 2012 at 12:47 AM.
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I would be buying a head gasket with a thickness that helps you get your required CR ( you did allow for the gasket thickness in your CR calc didn't you? )
And buy valve cover gaskets to suit what ever ( you don't say ) style head you will be running , centerbolt or perimeter bolt pattern
Thread Starter
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Joined: Aug 2011
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Neither.
I would be buying a head gasket with a thickness that helps you get your required CR ( you did allow for the gasket thickness in your CR calc didn't you? )
And buy valve cover gaskets to suit what ever ( you don't say ) style head you will be running , centerbolt or perimeter bolt pattern
I would be buying a head gasket with a thickness that helps you get your required CR ( you did allow for the gasket thickness in your CR calc didn't you? )
And buy valve cover gaskets to suit what ever ( you don't say ) style head you will be running , centerbolt or perimeter bolt pattern
Well after looking into it i think i can remove the intake without taking the plenum apart so I will only need head gaskets and intake gaskets
I did the calculations with the head gasket and am using a .039 fel pro right now
This is the calculator i used
http://www.csgnetwork.com/compcalc.html
Does anyone know if i need to have the water crossover passage blocked off? I see there are gaskets with and without it being blocked off(this is a 1990 corvette)
Found it and i do need it!
http://www.hotrodlane.cc/PDFFILES/TPIStory.pdf
Last edited by 76z28; Dec 3, 2012 at 01:05 AM.
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Joined: Jan 2004
Posts: 3,556
Likes: 13
Good luck
Genuine intake gasket from a alum head L98 engine has a restrictor plate with a small hole in it at rear coolant port
Genuine intake gasket from a alum head L98 engine has a restrictor plate with a small hole in it at rear coolant port
Thread Starter
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Joined: Aug 2011
Posts: 105
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Only thing i will need are the gaskets for the valve covers
I went looking for all the gaskets and they actually totaled more than it would be to order the intake gaskets themselves(after going out there and looking i cant get a socket or anything on a couple of the bolts so i would need to remove the whole plenum)
