Max out of the hole
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Max out of the hole
I'm assembling a ls engine for a friend and from my calculations its going to be .012 -.015 out of the hole. I have a .051 head gasket right now and could go thicker if needed. How much is too much out and what is the min quench I'll be safe at. Ive been told .038 -.040. Its a ls6 with a wiesco forged piston. wiesco 6.125 rod and stock crank. Its going to see a max rpm of 7200 road race car.
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Re: Max out of the hole
Not advanced. You can get any thickness gasket you need. Get it assembled and figure from there.
GURU is only a name.
Adam
Adam
Re: Max out of the hole
I have built several with the piston .012/.015 above the deck and used a .046 gasket with no
Reported problem.
Put it to get her and drive it like you stole it.
John
Reported problem.
Put it to get her and drive it like you stole it.
John
Re: Max out of the hole
Your combination should be OK.
Are you going to install the limiter chip and a locking tell-tale tach? Never believe a driver or a friend on a race track. They only shift when they're ahead.Its going to see a max rpm of 7200 road race car.
Jack Vines
Studebaker-Packard V8 Limited
Obsolete Engineering
Studebaker-Packard V8 Limited
Obsolete Engineering
Re: Max out of the hole
I am currently building an engine & have deliberately had the block decked so that the pistons are 0.010" out of the hole. 0.039"head gasket. Trying to cheat the octane fairy. Engine will be limited to 6000 rpm.
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Re: Max out of the hole
.015" out of the hole means it will grow to .020" when at normal temp, but if you have Aluminum heads concider it a wash!
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
Re: Max out of the hole
Aluminum block? I have done quite a few that were .006 to .008 above deck and used a .036 cometic..aluminum head, aluminum block LS. Your clearances above will be fine, even if its iron.sccagt1racer wrote: ↑Wed May 16, 2018 6:34 pm I'm assembling a ls engine for a friend and from my calculations its going to be .012 -.015 out of the hole. I have a .051 head gasket right now and could go thicker if needed. How much is too much out and what is the min quench I'll be safe at. Ive been told .038 -.040. Its a ls6 with a wiesco forged piston. wiesco 6.125 rod and stock crank. Its going to see a max rpm of 7200 road race car.
- af2
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Re: Max out of the hole
Ya me too. On a typical blown Brad we see .014" growing from hot to cold. HMM If the piston was out it will stay out!
GURU is only a name.
Adam
Adam
Re: Max out of the hole
I've run 100s of laps with a motor that is .027 out of the hole with a.070 cometic gasket..040 is what shoot for.
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Re: Max out of the hole
Re working a 489 that is using a .061" Felpro and will get the same one at .039" total clearance using Aluminum heads now.
GURU is only a name.
Adam
Adam
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Re: Max out of the hole
the aluminum block will grow .005 so you will be .005 less than room temp measurementsccagt1racer wrote: ↑Wed May 16, 2018 6:34 pm I'm assembling a ls engine for a friend and from my calculations its going to be .012 -.015 out of the hole. I have a .051 head gasket right now and could go thicker if needed. How much is too much out and what is the min quench I'll be safe at. Ive been told .038 -.040. Its a ls6 with a wiesco forged piston. wiesco 6.125 rod and stock crank. Its going to see a max rpm of 7200 road race car.
Re: Max out of the hole
There have been a number of S/T threads on ideal piston/head clearance and 0.040" seems to be well-accepted as a good target for iron blocks with steel rods. Most feel ten thous 'too much' is way better than five thous too little, but there are numerous builders that are prepared to fly much closer to the sun; down to 0.030" and even a tad less.
Felix, qui potuit rerum cognscere causas.
Happy is he who can discover the cause of things.
Happy is he who can discover the cause of things.
Re: Max out of the hole
Closest ive gone is .028" on an iron headed ford 351C. Im still scared when i think about it.