difference between on center and off center

[earlbrown]

Sounds WAYYYYYY too complicated for absolutely no reason whatsoever lol. Just center everything and be done with it lol. It actually sounds like more work to go out of your way to ensure it wasn't on center lol.

Because they'd be back to having a rough running odd fire engine that wouldn't sell as well.


It was less work to flat spot the rods and use the same block and heads. It was defiantly a compromise decision that they got away with.

 

[gnxtc2]

Billy, is this for StageII heads when you are talking about headers, rockers and lifters? My Dad had a 3.8 StageII motor and went to a 4.1 on center StageII and aside from the rods, pistons and intake. The heads, headers, lifters and rockers were transferred over.

No, Stage heads are whole different animal.

When using an on-center block, the banks (1-3-5) and (2-4-6) are shifted approximately .120"-.125" from each other. The lifter bores don't move. Either you're going to need offset lifters or offset rockers/machine the heads to get the valvetrain geometry correct. When you bolt the heads on, the banks are shifted. The headers need some type of adjustment to make up the difference. The TA headers already have the adjustment built into them ie: V-bands by each header and slip fitting on the crossover.

Billy T.
gnxtc2@aol.com

 

[MCH86GN]

I'm pretty sure the TA blocks are the same casting between on and off center. It's the final machining where the bore sleeves land and any mods to the main saddles that would matter. Don't take that as gospel though I've never laid actual hands on an on-center block.

When the Buick V6 became an even fire engine it got a split pin crank. That means there's a small flap of metal on the center of the journal pairs where there used to be just one big wide journal (like a SBC). Since that flap takes up space it pushes the rods away from each other. So the rods have a 'flat' machined on one side of the big end to move them closer together. It just doesn't move them back to the center of the bore. Kind of an average between the two.

That's the easy way to tell which direction the rods go. The flats face each other and there's a 45 on the balance weight to verify it after install.

Nice explanation. Since I had no, not a single bit of experience with cars until I bought my GN at age 35 I had to find an explanation of what splitting the crank pin meant. I knew what an engine was, but I didn't even understand the function of a CAM or know the different between OHV vs OHC engines. Learned a lot quick, but took a rash of crap from people. Finally got an explanation of odd fire vs even fire on a video called driving 4 answers. In order to keep a common crank pin and have an even fire engine the v6 would have to be a 120 degree v engine which makes it too wide.

 

[Chuck Leeper]

On center (OC) and off center (OC) are measurements used in construction and engineering to determine the distance between two points or objects. The key difference between the two is where the measurement is taken from.
"On center" refers to a measurement taken from the center of one object to the center of another object. For example, if you are measuring the spacing between two screws on a piece of wood, the measurement would be taken from the center of one screw to the center of the other screw.
"Off center" refers to a measurement taken from one edge of an object to another edge of an object. For example, if you are measuring the distance between two walls, the measurement would be taken from one edge of the wall to the other edge of the wall, rather than from the center of one wall to the center of the other wall.
In summary, "on center" is a measurement taken from the center of an object to the center of another object, while "off center" is a measurement taken from one edge of an object to another edge of an object.

You should limit your "explanations" to your tax service clients!
Otherwise, the ban hammer will be applied.

 

[Jonasterg]

That account is a bot. Sounds like they generated text via ChatGPT (or similar)... It's semi-coherent but not actually relevant.

All of that accounts posts are similar. Recommend the hammer!

 

[Chuck Leeper]

That account is a bot. Sounds like they generated text via ChatGPT (or similar)... It's semi-coherent but not actually relevant.

All of that accounts posts are similar. Recommend the hammer!

Done!

 

[Mr URL]

Look up the difference between Stage engines and stock engines. Lot to learn between what it is. And they can be different on either side. There are also Stage 1 engines which are rare super stock engines. On center, off center, even fire, and odd fire. It's complicated.

 

[Chuck Leeper]

There are also Stage 1 engines which are rare super stock engines.

That's an exciting revelation.....

 

[Mr URL]

That's an exciting revelation.....

Red Armstrong was a great example of someone using them. He had one in his wives Limited. That is why it ran 9's and looked almost bone stock. He went through great lengths to keep it looking stock. If it wasn't for the Stage 1 it would not have gone that fast to hold that amount of power.

 

[Mr URL]

If I remember right he ran a 9 with a TA stock looking turbo. Stock intake housing. Not TE. I'm sure his boost was about 35 psi to 40 psi.

 

[Mr URL]

Red always liked low timing and a ton of boost with tons of fuel. That is how he always went fast.

 

[Mr.Spool]

Red Armstrong was a great example of someone using them. He had one in his wives Limited. That is why it ran 9's and looked almost bone stock. He went through great lengths to keep it looking stock. If it wasn't for the Stage 1 it would not have gone that fast to hold that amount of power.

This is incorrect
Their are several of us that have gone faster on production stock blocks
They can hold the power.