3.0 combustion chamber volume?

[emcon5]

Does anyone know off the top of their head (no pun intended) the cc volume of a stock 3.0 litre head?

I am doing some Jethro Bodine Cipherin' on compression ratios, and am getting some "interesting" results.

Thanks,

Tom

[ruf-porsche]

Originally posted by emcon5
Does anyone know off the top of their head (no pun intended) the cc volume of a stock 3.0 litre head?

I am doing some Jethro Bodine Cipherin' on compression ratios, and am getting some "interesting" results.

Thanks,

Tom

Hummmmmmmmmmm Let see

If my high school math doesn't fail me there are six cylinders to a 911 engine and if the engine is 3.0 litre that mean each cylinder should be ~ .5 litre?

I don't think Jethro finish grade school he was to busy porkin Elle May, after all they were only cousins.

[emcon5]

That is the engine displacement, not what I am looking for.

To compute compression ratio, you need the (V1)swept volume (aka displacement), (v2) deck height volume, (V3)cylinder head volume, and (V4) piston dome volume.

I just need to know what the head volume. It can be calculated I am sure, but it is usually measured by filling the head up with a liquid. Also known as CC-ing the head.

the formula is:

V1 + V2 + V3 - V4
--------------------- = compression ratio
V2 + V3 - V4

Tom

[ChrisBennet]

Let me guess, you're finding that the factory compression ratios are a bit higher than what you get when you actually measure them?
-Chris

[emcon5]

Slightly lower actually, but not factory parts. Chris, do you remember what your head CC was?

Tom

[ChrisBennet]

Tom,
I have a 3.2 so I don't know if it relative, but my head volume was 91.3 cu cm. They varied a bit from head to head. a 3.2 measures out to a true 9.2:1 CR I think. The factory says the compression is something like 9.5:1.
-Chris

[emcon5]

Originally posted by ChrisBennet
Tom,
I have a 3.2 so I don't know if it relative, but my head volume was 91.3 cu cm.

Was that with a 95mm or 98mm bore?

Tom

[Jadams1]

3.0 - 6(bore X stroke)
--------------------------- = volume of cylinder head ???
6
Is a 3.0L just the result of the stroke X bore or does it include the head volume too?

[ChrisBennet]

Originally posted by emcon5
Was that with a 95mm or 98mm bore?

Tom

3.0 and 3.2 are both 95mm bore. The 3.2 is just has a longer stroke.
-Chris

[emcon5]

Originally posted by ChrisBennet
3.0 and 3.2 are both 95mm bore. The 3.2 is just has a longer stroke.
-Chris

I know, I just didn't remember if your car was a factory 3.2 or a short stroke.

Tom

[ChrisBennet]

Tom,
I getcha now, it was a factory 3.2. (It's now 98mm and has a different head volume but that's another story.)
-Chris