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440 stock deck height

Garys1969RR

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Found a 1969 440 Magnum, came out of a Charger. Just want to see what the stock deck height is with that motor, from the factory. Are the pistons about .017 below deck? Or is it more like .050" ? I can use some parts off it to beef up my low compression RV motor, and possibly use the Hi Perf factory cam out of it. So C Height on those pistons is what I need to know. Anyone have one they can measure? OK thanks.
 
Darn, not enough! The six pack motors came with around .010 to .015, right? I Had a 440 with the L2355F pistons, came to about .010 below deck. Anyone need a nice 69 block?
 
a 1969 440 Magnum
That's what I started out with, out of an RT. Just me, but prefer 68-70, nothing later.
Sure don't remember in the hole #s, stock HP parts, though parts would be good, crank, rods, so on.
 
The stock 440's I had, both the std & HP seemed around .030 - .040. I milled them at least .020 to get .010 with the 11.5 TRW piston. Later 440's had more deck height due to the change in pin CL to piston top.
 
The CR for the 2.030 flat piston with no valve pockets is the same as the 2.062 piston with valve pockets.

If you’re using open chamber heads, you get no benefit of better quench with the 2.062 piston.
In that situation the only advantage with them would be if you were running a big enough cam that you needed the valve pockets.
 
Right. I would like to build some quench into the motor, so looking for the right piston. The 2355s have the right C Height st 2.067, but that piston is 1067 grams! Icon has a lighter one, around $ 600 for the set of 8. May just build a 451, and get some REALLY LIGHT pistons.
 
Was wondering what the build date and serial number was for the block?
 
one of my 440 builds used the TRW 2355 which with the 2.062 CH usually comes out down 10-15
however the block was so bad-( down on one corner which you can't find with calipers)
that when squared up with my BHJ "block true" tooling ended out of the hole .015
Using ported 915 heads with chambers opened up 5 cc
ended up using solid stainless core Marine gaskets and D-Dished the pistons dished like the popular TRW "turbo" piston (that's SBC popular) for 9:1
was for a motorhome was a six pack core with the heavy but not primo materiel rods (actually a 73 HP core which used the 6 pack balanced crank and heavy rods) else use the lighter LY rods with DC rod bolts and the much lighter pistons (and thinner rings) available today
heck if going through all that a stroker kit starts to make sense
OP
nothing you can do with those pistons to get quench with open chamber heads
throw that worn out 50 year old cam away
block, crank and rods can be used and get the KB pistons made for the open chamber heads if you are going to use stock heads- they give you the quench you need
figure out your CR and post back CC your heads- they vary enough to make a difference
pick the .028 Mr Gasket or the stock thickness gasket and figure both ways
shoot for .035 quench max- although .050 is on the edge of working
the motor I described above ended up at .025- still running almost 40 years later
 
Off topic a bit...
but who here has DYNO Tested different quench distances on a BB Mopars ? and what did YOUR testing indicate ?
or,
can anyone direct me to some actual Dyno data/testing others have done on the internet regarding this subject ? hopefully specific to BB Mopars ?

 
Right. I would like to build some quench into the motor, so looking for the right piston. The 2355s have the right C Height st 2.067, but that piston is 1067 grams! Icon has a lighter one, around $ 600 for the set of 8. May just build a 451, and get some REALLY LIGHT pistons.


Don't sweat the quench, .045" is fine, tighter can actually LOSE power depending upon Head Flow efficiency/size of the Engine/Camshaft.

ICON makes a nice Piston we use on the budget street 440's, the 9953, it comes in right around 814 grams ? I think ? with the Pin ?
Cheaper 5/64" Rings but fine for that peak speed in a street deal
But they LIE about the Flycuts which I think are closer to 8 CC's (7.6 or so)
 
If I can get it set up with 30 quench I'll do it before I go 45 but 45 will work too. By the way a 50 down piston will yield 10.3 to 1 in a stock bore 440 with closed chamber heads and steel shim gaskets but then you end up with .070 quench..... And that can vary .010 . Factory deck height from Crank Centerline can vary that much.
 
I posted a pretty good article some years back on the subject....probably lost in space by now lol. Years ago I helped a buddy build an engine...rather he was helping me which I don't like doing. I was doing some machine work while he was supposed to be checking piston to head clearance. When I got done with the parts, he already had the heads on so I just assumed he checked it like he was supposed to have done. This engine went into a 3500+ lb car and it ran a 10.0 right off the trailer. Cool....but after making the 3rd pass and checking plugs etc things weren't so cool when he decided to hit the funny gas button. It blew out a cylinder right off the line at the hit. Upon tearing apart, I found it only had .019 piston/head clearance. After saying to him "you didn't check it before slamming the heads on...." His reply was "I thought you did it" lol. Anyways, we were able to get it back together right this time and it duplicated the some ET and with a small shot (according to him :D), it ran 9.30's. Not too shabby for a couple of hicks imo.
 
I posted a pretty good article some years back on the subject....probably lost in space by now lol. Years ago I helped a buddy build an engine...rather he was helping me which I don't like doing. I was doing some machine work while he was supposed to be checking piston to head clearance. When I got done with the parts, he already had the heads on so I just assumed he checked it like he was supposed to have done. This engine went into a 3500+ lb car and it ran a 10.0 right off the trailer. Cool....but after making the 3rd pass and checking plugs etc things weren't so cool when he decided to hit the funny gas button. It blew out a cylinder right off the line at the hit. Upon tearing apart, I found it only had .019 piston/head clearance. After saying to him "you didn't check it before slamming the heads on...." His reply was "I thought you did it" lol. Anyways, we were able to get it back together right this time and it duplicated the some ET and with a small shot (according to him :D), it ran 9.30's. Not too shabby for a couple of hicks imo.
I assume adding nitrous to the equation you would have to increase the piston to valve clearance? I have zero experience with the funny gas, but hope to play with it someday.
 
I assume adding nitrous to the equation you would have to increase the piston to valve clearance? I have zero experience with the funny gas, but hope to play with it someday.
Yes....and rods will too depending on the length and material. Aluminum rods need a good deal more but that's mostly with the piston to head clearance. Deeper valve reliefs are usually required too but those are usually already pretty big in most pistons. Thing is to check all of that stuff. Even changing the timing on the cam will have an affect on it....
 


Thx, Good propaganda Article for Cometic Head gaskets ?
But I don't see any actual research data on quench distances in the article ? Maybe I missed it ?

We've seen Power Losses on the Dyno below .040" quench on 4.350" Bore BB Mopars, and conversely, on 4.500" Bore BB Mopars we can see GAINS of up to 35 HP by increasing the quench to .065" to .075" on 440-1 and 572-13 INDY Heads ? and we have been seeing it for well over a decade now ?

Hence I was wondering just "where" this really TIGHT QUENCH rule has come from with BB Mopars ?

Just say'in here.... and only IMO,
There is far more to this "one size fits all" sub .050" Quench dimension as being BEST on everything from a 3.91" Bore 318 with Valves opening on center of the cylinder.... to 4.00" Bore Cheb/Ferd.... to a 4.350" or 4.500" BB Mopar with valves opening on the backside of the cylinder ? and it shouldn't be thought of strictly from an "as tight as possible until the Rod stretchs and the Piston Hits" criterion ?
 
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I posted a pretty good article some years back on the subject....probably lost in space by now lol. Years ago I helped a buddy build an engine...rather he was helping me which I don't like doing. I was doing some machine work while he was supposed to be checking piston to head clearance. When I got done with the parts, he already had the heads on so I just assumed he checked it like he was supposed to have done. This engine went into a 3500+ lb car and it ran a 10.0 right off the trailer. Cool....but after making the 3rd pass and checking plugs etc things weren't so cool when he decided to hit the funny gas button. It blew out a cylinder right off the line at the hit. Upon tearing apart, I found it only had .019 piston/head clearance. After saying to him "you didn't check it before slamming the heads on...." His reply was "I thought you did it" lol. Anyways, we were able to get it back together right this time and it duplicated the some ET and with a small shot (according to him :D), it ran 9.30's. Not too shabby for a couple of hicks imo.

LOL !
ran LOTS of tight engines in the late 70's/early 80's.
at the risk of dating myself a bit..... we used to be able to actually read the "L2295" or "7025P" right off the bottom side Cast Iron 915 Heads when removed from the Aluminum Pistons touching @ rpm
And remember....
those Pistons C.D. is normally .050" down.... so gives an idea how much we would Mill the Blocks, and playing with ever diminishing returns Flycutting Pistons to clear the Cam Lift.

 
WE did lots of dyno work on quench on 440 Transit bus motors of City Of San Jose Ca
Tried welding up the chambers to 915 style
gave it up and developed a piston which was put into what became the KB quench piston
Agree with Cranky on quench distance
Remember you are dealing with two phenomena
one is the quench of two cold surfaces in close proximity
the other is the squish> jet of gas> turbulence of gas exiting the quench area
on some builds there is to much gas jet and it sorta blows out the fire
so you reduce the size of the quench area (not open the gap)
Notice how many later motors have two quench pads
quench all the way around
just check your burn patterns
ON the busses adding quench and reducing the long ramps on the cam and decreasing overlap (keeping the valves on the seats as long as possible) reduced EGT 800 degrees
Performance on gasoline is very similar results
I'll add that open chamber heads can make great power as long as you have the revs above the torque peak (BMEP peak)
Closed chamber tight quench works from idle up
less sensitivity to timing and bad gas
we even put quench into Hemis two ways
ring all the way around except for valve reliefs
and
dome close to the chamber (away from the valves)
 
WE did lots of dyno work on quench on 440 Transit bus motors of City Of San Jose Ca
Tried welding up the chambers to 915 style
gave it up and developed a piston which was put into what became the KB quench piston
Agree with Cranky on quench distance
Remember you are dealing with two phenomena
one is the quench of two cold surfaces in close proximity
the other is the squish> jet of gas> turbulence of gas exiting the quench area
on some builds there is to much gas jet and it sorta blows out the fire
so you reduce the size of the quench area (not open the gap)
Notice how many later motors have two quench pads
quench all the way around
just check your burn patterns
ON the busses adding quench and reducing the long ramps on the cam and decreasing overlap (keeping the valves on the seats as long as possible) reduced EGT 800 degrees
Performance on gasoline is very similar results
I'll add that open chamber heads can make great power as long as you have the revs above the torque peak (BMEP peak)
Closed chamber tight quench works from idle up
less sensitivity to timing and bad gas
we even put quench into Hemis two ways
ring all the way around except for valve reliefs
and
dome close to the chamber (away from the valves)


All fine and dandy, but as we are seeing on the Dyno, too tight quench distances on BB Mopars is Killing power ?
which,
time and again we can gain right back merely swapping a thicker Head Gasket with NO other changes, done right on the Dyno and re-run.
It's all "relative" of course to the Engine/Cam/Head Flow.... but we're seeing Lots of Combo's where tighter than .040" actually LOSES power, the bigger the bores the MORE the losses.

No wars wanted, you can do as you please obviously.....
just say'in here, that's what we've seen.

 
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