440 RB stock Pistons

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Bill Mandaro

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Hey y’all, hoping I can get some help with installing my stock pistons, I had them organized by cylinder but during a recent deployment my brother in laws helped my wife move houses and the pistons got mixed up. I know the dimples face the front of the engine but not all the dimples are the same size and I can’t remember which goes where.

Any help or advice on a greatly appreciated.
 
Are the rods still on them? They are numbered. If rods off then look on the underside,
The factory pistons and the piston pins are offset to one side.
 
Are the rods still on them? They are numbered. If rods off then look on the underside,
The factory pistons and the piston pins are offset to one side.
Rods are still on, I didn’t know they were numbered I’ll look for that thank you
 
If they got mixed up and your rods are not numbered perfectly you'll just have to measure all the bores and all the pistons to decide which holes to put them in.

Tom
 
If the pistons are off the rods, you have a great opportunity. But yourself a digital scale that reads grams that will go to the highest weight of your rod or piston. I checked weight on each piston, rod and wrist pin and recorded. You can then match rods, pins and pistons to the get the most consistent weight across the set. Doing this simple mixing/matching, I achieved less than 3-gram difference from the heaviest piston/wrist pin/rod to the lightest. This was on a small block Ford and even with ~220@ .050/.517 lift cam, the engine idled rock smooth and was great running little engine. Minus the crank, you're balancing the rotating assembly yourself for the cost of a digital scale. I think I paid less than $50 for one I bought on Amazon. Then take each matched piston/wrist pin/rod to the machine shop and have them assembled.
 
Rods are still on, I didn’t know they were numbered I’ll look for that thank you
Good for you. They are numbered on big end, outboard side of rod and rod cap, same side as the groove for the bearing tang.
 
The arrow on the piston [ or could be dimple or notch ] goes to the front of the engine. There are 4 left & 4 right. Now look at the big end of the rod, where the bearing shells fit. One side of the rod has a noticeable chamfer, the other side does not. The chamfered side goes against the crank cheek....with the arrow on the piston pointing forward.
 
So I finally had a chance to get back in the garage and I can’t find any numbers identifying the individual pistons. However 4 are marked with a spade, club, heart, diamond. And the other 3 have a bell, octagon, puzzle piece. And 1 has nothing

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The symbols mean a later model 440. I'll dig up my notes that I have for a 1977 400 that I tore down and rebuilt. The symbols that correspond with my cylinders may or may not apply to your 440, but it might be a way double check your findings with bore/piston measurements.
 
The symbols mean a later model 440. I'll dig up my notes that I have for a 1977 400 that I tore down and rebuilt. The symbols that correspond with my cylinders may or may not apply to your 440, but it might be a way double check your findings with bore/piston measurements.
Thank you!
 
1977 400 cylinder to connecting rod symbol:
#1 = octagon
#3 = star
#5 = square (really a light strike - possibly a puzzle piece?)
#7 = bell
#2 = spade
#4 = club
#6 = heart
#8 = diamond
 
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