[INJUNTOM]

Piston in the pic has the notch to the right side of the piston, the rod chamfer side is to the right, and the bearing tangs and squirter hole is up in the pic - just as if it belongs on the right bank (passenger side), but is marked #1 on the rod. I'm guessing someone either got the bank wrong when they marked them in the past or maybe didn't really even know where they should be? Maybe I'm missing something. Been a couple years since I built one.

Back story is this is a 326 out of a car I drove as a daily driver for several years, ended up parting the car out, pulled the engine apart to freshen and reseal and never got back to it, now a few years later going back together, this caught my eye.

[johnta1]

It depends on if the #2 is also 'backwards'?

Might be they were trying the high performance trick of doing them backwards?
(using the offset of piston pin)

[jww]

Maybe some Chevrolet guy put the rods on those pistons....happened to me!

[johnta1]

Piston in the pic has the notch to the right side of the piston, the rod chamfer side is to the right, and the bearing tangs and squirter hole is up in the pic - just as if it belongs on the right bank (passenger side), but is marked #1 on the rod.

The rod chamfer to the right would make the rod a #1 (driver side) position.

[grivera]

Originally Posted by johnta1

The rod chamfer to the right would make the rod a #1 (driver side) position.

If he's referring to the right in the picture, the chamfer would be in the wrong spot for number one position. As pictured, the chamfer would have to be on the left.

[johnta1]

We're talking about Pontiac crank, correct?

[grivera]

Originally Posted by johnta1

We're talking about Pontiac crank, correct?

OP said it's a 326.

[johnta1]

Where would you put this rod in this pic?
Red arrow or blue arrow?

[grivera]

Originally Posted by johnta1

Where would you put this rod in this pic?
Red arrow or blue arrow?

In the position where red arrow is pointing which is #2 position. On a Pontiac, the forward bank is #2 - unlike a Chevy. Obviously the assembly is incorrectly labeled.

[STEELCITYFIREBIRD]

Regardless of what you want to do with the piston, the rods should be positioned so the bearings on each crank pin are closest to each other, and if the rods are machined correctly(only stating this because of some possible anomalies on aftermarket rods ) the larger chamfers will be away from the other rod on the same pin, or put another way...large chamfers farthest away from each other for each pair of rods.

Red arrow position! X2

[johnta1]

Now what do the other 7 piston/rod combos look like?

[INJUNTOM]

Well, we all know John has built a successful engine or 2. Yes, the chamfer is to the right in the pic, same side as the notch, pin hole up and stamped number pads down, as if it belongs in the #2 position on the passenger side of the block. All the ones marked odd match that layout and all the ones marked even look to be correct for the driver's side. I suspect they marked it thinking the farthest forward rod was #1. An old machinist buddy who did engine machine work out of his garage told me that a lot of guys called him trying to find out why the engine locks up when they put in the #2 rod because they keep trying to put it in front of #2.

More on this engine: My '67 Convertible got hit back in 2002, so I bought a super clean '67 Tempest 4 door for a parts car, but it ran so good I used it for a work car for years. 326 ran great, got close to 20 MPG on the freeway, didn't use oil. Someone offered too much for the front clip, so I pulled it apart and plan to put the 326 in my wife's Firebird with 700R and 3.23 gears (car previously had 400/700R and 2.73). Pulled the engine apart and found that it had been apart before, but so long ago that I suspect it was done early on on warranty. Still standard.

Now it's getting '69 #62 heads, blended bowls/gasket match, crank polished, rings/bearings/oil pump/T set. Original Pontiac cam, which works very well with the 700R going into lockup at low RPM. I'm running 670 heads on a 350 block/700R/3.43 in my '67 Convertible now, so I'm going to see what happens with this.

[INJUNTOM]

Ha, you posted while I was typing a long winded reply. Looks like I just need to swap banks right? Just making sure I'm not missing something here.

Hey, does anybody else know what other engines have bank 2 furthest forward? I'm in the auto repair industry and always curious to see what different engines are, but there really aren't many. I'm probably forgetting some, but I'm pretty sure International is one of them.

[johnta1]

So if the pistons/rods are installed with the odd bank on even, etc, the pistons point to the rear?
(rod chamfers correctly on crank)

If so, there would be no problem really switching side to side.
(those piston valve reliefs can go either way)

[INJUNTOM]

Originally Posted by johnta1

So if the pistons/rods are installed with the odd bank on even, etc, the pistons point to the rear?
(rod chamfers correctly on crank)

If so, there would be no problem really switching side to side.
(those piston valve reliefs can go either way)

If the even are on the odd side, and the odd side on the even, it has the notches on the pistons forward, the rod chamfer side to the crank fillet radius, bearing tangs up, squirt hole up, and the stamped numbers visible from the underside. Good thing the engine doesn't know they were marked wrong...

[johnta1]

Yep.
Just remember that they are switched for the next tear down.

[INJUNTOM]

Hopefully won't be a next tear down. Will be a sunday cruiser. Used to be her daily driver for about 10 years, but we took it off the road close to 10 years ago due to not wanting some asshole to smash it for us. I would remark them, but everything is together, greased, and ready to drive in, so I'll let the next guy be just as confused lol

[Kenth]

Originally Posted by johnta1

So if the pistons/rods are installed with the odd bank on even, etc, the pistons point to the rear?
(rod chamfers correctly on crank)

If so, there would be no problem really switching side to side.
(those piston valve reliefs can go either way)

The piston pin sits offset in the piston.
Thus the notch on piston top.
Obviously turning the piston 180° the offset will be in the wrong location.

[johnta1]

The piston pin sits offset in the piston.
Thus the notch on piston top.
Obviously turning the piston 180° the offset will be in the wrong location.

That is correct.

But a lot of racers would turn them around for a slight power (possible) increase.
With a single valve relief (trough), one cannot turn them around.

That's why I asked my original question.
Possibly someone did install them for that reason.

With the valve reliefs the same for either position, the off-set is the only difference.

[gtofreek]

According to what you posted in your first post, the piston is mounted correctly. Keep in mind the #1 cylinder is on the drivers bank, and the bearing tang notch and oil squirter hole need to face in towards the cam, not out towards the oil pan rail like you have pictured. The way you are holding the piston in the picture would be for if you put it in the passenger side.