.040" Squish
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Intermediate
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.040" Squish
So I get the heads and jugs back yesterday and I checked the piston protrusion. Forgot the diesel liner protrusion dial indicator at work so used a feeler guage. The piston is .010 (closer to .0105) below the deck. With the .030 head gasket I will have .040 squish. I have heard that using .010 base gaskets is not a good idea.
Is the .010 that big of an issue or best to bite the bullet and send the jugs back to the machine shop yet again.
Is the .010 that big of an issue or best to bite the bullet and send the jugs back to the machine shop yet again.
Seasoned HDF Member
Joined: Feb 2013
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From: New York
I just read an article from American Iron Magazine about the .040 squish. I think it was the latest issue # 337. The article was by Donny Peterson under "Techline". It mention the stock Evo and TC motors have a .040 squish to cause turbulence at top dead center which mixes the air and gas.
Road Captain
Joined: Sep 2014
Posts: 695
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From: New Braunfels, TX
There's going to be some crush in the gaskets. Do you have an old set that you can assemble with and use some solder wire on the piston to squish and then measure? 2 thousandths off each gasket is pretty common (unless mls headgasket) which would put you at .036 squish which is a hell of a lot better than factory. I take it you're targeting .030?
Some quick googling tells me that Cometic redesigned their base gaskets sometime last year so that might be worth looking in to, the problems you heard about might not exist any more. If It were me I'd run the .010 gaskets with a thin coat of hylomar or copper spray plus a surgical cleaning of sealing surfaces, but only after checking the squish with some solder. I'm just not so confident in a feeler gauge measurement but you were there so if you're confident go with it. My only word of caution is you don't want to actually end up at .026 or even less with possible gasket crush plus unknown measurement variance.
Some quick googling tells me that Cometic redesigned their base gaskets sometime last year so that might be worth looking in to, the problems you heard about might not exist any more. If It were me I'd run the .010 gaskets with a thin coat of hylomar or copper spray plus a surgical cleaning of sealing surfaces, but only after checking the squish with some solder. I'm just not so confident in a feeler gauge measurement but you were there so if you're confident go with it. My only word of caution is you don't want to actually end up at .026 or even less with possible gasket crush plus unknown measurement variance.
Thread Starter
|
Intermediate
Joined: Mar 2010
Posts: 44
Likes: 1
There's going to be some crush in the gaskets. Do you have an old set that you can assemble with and use some solder wire on the piston to squish and then measure? 2 thousandths off each gasket is pretty common (unless mls headgasket) which would put you at .036 squish which is a hell of a lot better than factory. I take it you're targeting .030?
Some quick googling tells me that Cometic redesigned their base gaskets sometime last year so that might be worth looking in to, the problems you heard about might not exist any more. If It were me I'd run the .010 gaskets with a thin coat of hylomar or copper spray plus a surgical cleaning of sealing surfaces, but only after checking the squish with some solder. I'm just not so confident in a feeler gauge measurement but you were there so if you're confident go with it. My only word of caution is you don't want to actually end up at .026 or even less with possible gasket crush plus unknown measurement variance.
Some quick googling tells me that Cometic redesigned their base gaskets sometime last year so that might be worth looking in to, the problems you heard about might not exist any more. If It were me I'd run the .010 gaskets with a thin coat of hylomar or copper spray plus a surgical cleaning of sealing surfaces, but only after checking the squish with some solder. I'm just not so confident in a feeler gauge measurement but you were there so if you're confident go with it. My only word of caution is you don't want to actually end up at .026 or even less with possible gasket crush plus unknown measurement variance.
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northeastconfederate
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Jul 14, 2011 06:54 AM
