I want to know the differance between decking a block to bring the pistons as close to .ooo" as possible vs using a thinner head gasket to achieve the same piston to head clearance.
The mods that I am planning are in my sig.


Steve

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91RS, 4L60 w/B&M Megashifter, 350vortec, 9.4cr,Combustiom chambers and pistons polished and coated w/ techline thermal barrier coating, LT4 Hot Cam Kit, RPM Air Gap, 454TB w/350injt, Headman shortys, 3" catback, 323posi, did I leave anything out?

 

the deck measurement is from the deck surface to the top of the piston. if you run zero deck measurement the top of the piston is flush with the block. thick or thin gaskets won't change this. the differant gasket thickness will change the disance from the top of the piston to the head.

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ICON Motorsports

1st & 3rd
MM Black Diamond 538 F&AM

 

What I wanted to know was, is there a differance if say I want to run a .040 piston to head clearance in how I go about doing this and the advantage of one over the other. If my piston is at -.020 in the bore and I use a .020 thick head gasket to get my specified clearance will this work as well as having .000 deck height and using a .040 thick head gasket? I do not want to mill the block if I don't need to.

Steve

 

Steve,

If you don't need to mill the block to regain a square deck at the correct height, then don't. If you can accomplish whatever clearances you need with valve depressions and head gaskets, you're lucky.

Achieving 9.4:1 static compression is fairly easy with stock deck and gaskets. If valve clearance is an issue, you might want to flycut the reliefs in the pistons for extra clearance, but you have to do better than an LT4 "hot" cam to get interference unless you've done something unusual with the heads.

Am I missing part of the equation?

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Later,
Vader
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"What a Day..."
Adobe Acrobat Reader

 

Thanks Vader, I don't think so. What I'm trying to do is make a tight qwench using a d-cuped piston to give me about 9.1/1 to 9.4/1 cr. With the tight qwench and good combustion chambers of the vortec heads along with coating the cc's and piston tops with Techline ceramic coating I hope to stay out of detonation and still be able to have a decent ign curve.

Steve

 

ok thats easy the gasket is cheaper and gives the same results!!

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89 firebird formula

356 10.5:1compression CURRENTLY DEAD!!! BEARING FAILURE!!
comp cams xe262 cam
performer rpm intake
#1405 edlebrock 600
sportsman 2 heads 64cc 2.02/1.60 valves 200cc intake runner
msd 6al
h.e.i. proform 50,000 volt vac. advance ditributor
700r-4 with 3.08 first gear and 3.23 posi 7 5/8 rear end.
b trans shift kit(will kill shifts...suck dong!!)
shorty heddman hedders with custom 3" pipe y-pipe back(no damn cat!) with 40 series flowmaster!


future mods: 406 roller REALLY REALLY REALLY RADICAL!!!!!

 

Thanks for the help everyone, I also could not see any differance but it's better to be safe than sorry.

Steve

[This message has been edited by steve8586iroc (edited April 16, 2001).]