Valve to Piston Clearance
I am bumping this thread because I feel starting a new one is pointless.
I went against all suggestions and assembled my motor w/o claying it, the machine shop didnt want to do it, and my long block assembler (sp) didnt want to do it either so I said w/e and bought a thicker headgasket
What I know about my motor
Pistons are +.016 out of the bore, Wiseco 8.8:1 Comp Height 30mm, Dome -12cc
My head has been cut 1 time by me for .010", my friend does not remember what he had cut off it, same shop did it, so I am assuming also .010" for a total of .020"
When I use a Displacement Calculator with all those variables, I entered in the column .065" for total amount milled/cut off head and block (I am pretty sure OEM unhacked the pistons sit .033" in the hole, mine are .016" out of the hole, so there has been .049" taken off my block and .020" cut off the head for a total of .069", i know its crazy
)
I am using a Cometic .065 Headgasket, which with all the above stuff entered into the calculator I get a Piston to Deck Height of -.034" which I dont make much of. The way I see it I have pistons sitting .016" out of the bore with a head that is .020" and a .065" gasket sandwiched in there for a Piston to Head clearance of of .029". I had a nice valve job done sinking the valves in slightly, all Valvetrain is Ferrea.
So knowing that, how much lift is associated with OEM GSR cams? I know this is totally the incorrect way of doing this, but my car is already running and tuned to 10k rpm w/o a problem with the cams gears altered to get my timing to 16deg base. I was told (i know #1 net mistake) that I have plenty of piston to valve clearance now and that it would also be safe to run a set of SK2 Tuner 2 Cams ( 12.4 Lift Intake, 11.9 Lift Exhaust).
How do you all feel about me swapping cams? I have a shop locally that I might pay (they want $400-500) to install a degree wheel onto my OEM Damper (cheaper price if I had a Fluidamper Installed) pull my vlavesprings and install softer ones and measure my P2V with a rather expensive loking device that I have seen before to get an accurate measurment. I know paying the price is cheap in comparison to a new set of pistons and my valves that cost $28 a piece. But the person that recommended the cam swap to me is very reputable, just this whole situation has me confused, and I would rather put the $500 elsewhere.
So in conclusion, who in here thinks my engine should already be a bucket of broken valves, and who think I am safe w/o spending $500 to check? I think I am playing with a ticking timebomb but when I hear that I am ok from someone I trust it throws me off.
I went against all suggestions and assembled my motor w/o claying it, the machine shop didnt want to do it, and my long block assembler (sp) didnt want to do it either so I said w/e and bought a thicker headgasket
What I know about my motor
Pistons are +.016 out of the bore, Wiseco 8.8:1 Comp Height 30mm, Dome -12cc
My head has been cut 1 time by me for .010", my friend does not remember what he had cut off it, same shop did it, so I am assuming also .010" for a total of .020"
When I use a Displacement Calculator with all those variables, I entered in the column .065" for total amount milled/cut off head and block (I am pretty sure OEM unhacked the pistons sit .033" in the hole, mine are .016" out of the hole, so there has been .049" taken off my block and .020" cut off the head for a total of .069", i know its crazy
)I am using a Cometic .065 Headgasket, which with all the above stuff entered into the calculator I get a Piston to Deck Height of -.034" which I dont make much of. The way I see it I have pistons sitting .016" out of the bore with a head that is .020" and a .065" gasket sandwiched in there for a Piston to Head clearance of of .029". I had a nice valve job done sinking the valves in slightly, all Valvetrain is Ferrea.
So knowing that, how much lift is associated with OEM GSR cams? I know this is totally the incorrect way of doing this, but my car is already running and tuned to 10k rpm w/o a problem with the cams gears altered to get my timing to 16deg base. I was told (i know #1 net mistake) that I have plenty of piston to valve clearance now and that it would also be safe to run a set of SK2 Tuner 2 Cams ( 12.4 Lift Intake, 11.9 Lift Exhaust).
How do you all feel about me swapping cams? I have a shop locally that I might pay (they want $400-500) to install a degree wheel onto my OEM Damper (cheaper price if I had a Fluidamper Installed) pull my vlavesprings and install softer ones and measure my P2V with a rather expensive loking device that I have seen before to get an accurate measurment. I know paying the price is cheap in comparison to a new set of pistons and my valves that cost $28 a piece. But the person that recommended the cam swap to me is very reputable, just this whole situation has me confused, and I would rather put the $500 elsewhere.
So in conclusion, who in here thinks my engine should already be a bucket of broken valves, and who think I am safe w/o spending $500 to check? I think I am playing with a ticking timebomb but when I hear that I am ok from someone I trust it throws me off.
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