piston to head clearence

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abdyguy

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Can anyone tell me what clearence is safe for a 440 with ly rods and trick flow heads. I looked in mp engine book and they say .055 to .060 is that correct? If so how can you get .035 quench.
 
.050 - .065 quench distance with aluminum rod,
 
I see no reason the stock forged rods fans flat tops at a zero deck height can't be used with a gasket of the required thickness.
The stock rods do not stretch so much as to worry IMO. I do it with the small blocks.
 
I thought thats what they ment but then it went on to say that the piston will physically hit at .045 with steel rods. So i guess my question is like i asked how close is ok. Thanks for your replies in advance.
 
I am unaware just how much the LY rod will stretch. I've run .028 on my small block. 0 deck 360.
 
Good deal thanks all for your help ill file the mp book where it belongs.
 
I would set pistons at zero deck and use a cometic .036 gasket.
 
People have run as little as .015 with steel rods and not hit. I would not, because that wouldn't be my luck. United Engine and Machine, who makes the Keith Black pistons, says .035 is optimal with steel rods.
 
Aluminum res do stretch a bit and I would play it safe at the recommended spec for sure.

Forged rods... Better the rod the closer you can run. .035 is great.
 
What is your piston choice? And what is the skirt clearance going to be? A loose fitting piston (when it is cold) will (rock, tilt) in the bore. This is when you can run into contact trouble with the piston touching the head with a tighter quench!
 
yellow rose said:
I doubt you will find 10 HP reducing the quench. The HP gain will come from the increase in compression.
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the quench will help keep it from pinging or detonating. not doing it for compression. I`ve got .039 on my 505. we used to run the hemi w/ them slightly kissing just enough to keep the carbon off at 6500- 7000. ran 14 yrs like that.
 
famous bob said:
the quench will help keep it from pinging or detonating. not doing it for compression. I`ve got .039 on my 505. we used to run the hemi w/ them slightly kissing just enough to keep the carbon off at 6500- 7000. ran 14 yrs like that.
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Ever actually test it on a dyno? I can never tell if it's from compression or quench. Never had anyone close up quench and keep th compression the same.

So, AFAIC if your under .060 and your compression is correct you are wasting time.
 
yellow rose said:
Ever actually test it on a dyno? I can never tell if it's from compression or quench. Never had anyone close up quench and keep th compression the same.

So, AFAIC if your under .060 and your compression is correct you are wasting time.
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about .040 quench will allow higher comp. w/o detonation.
 
famous bob said:
about .040 quench will allow higher comp. w/o detonation.
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This ^^^

Typically I set up my HP small blocks with a zero deck height and a .038 gasket for good quench. This works very well with ether open chambered X, J etc. heads or closed aluminum chambered heads like Edelbrocks.
I have run tighter quench. I normally do not like to push it so close. Top quality rods and attaching hardware should be used in this area. (Tighter quench)

I have been told that more than .050 quench is not good. The bennifit is lost at that point.
 
whitepunkonnitro said:
If the pistons aint slapping the heads, you're leaving power on the table
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Been told that my entire life. I actually have tightened the quench up and saw ZERO I could attribute to quench. I never found anyone to pay to tighten the quench and keep the compression the same.

Some chambers and some engines with retarded geometry are more sensitive to quench. Much worry for little
 
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