# [tcb] Re: Engine size

• From: Gerald Livingston <gerald.tcb@xxxxxxxxxxxxx>
• To: tcb@xxxxxxxxxxxxx
• Date: Wed, 30 Nov 2011 23:34:49 -0600
```THERE it is!!

I just knew building an engine required fresh PI(E).

But your equation gives him a 1907353.88895744cc engine.

It's actually:

((bore/10) x (bore/10) x (stroke/10) x (3.14159265 / 4) x cylinders))

/10 puts BORE and STROKE in cm, not mm

OR, since we have a 4 cylinder engine we can use:

(bore x bore x stroke x 3.14159265)/1000

rather than dividing the bore and stroke by 10 abd pi by 4 and then
multiplying the result of that by 4 again

so,

8.8 x 8.8 x 7.84 x .785398162 x 4 = 1907.353887743 cc

OR

88 x 88 x 78.4 x 3.14159265 / 1000 = 1907.353888957 cc

for 88mm pistons and a 78.4mm stroke

G2

On Wed, 30 Nov 2011 22:26:41 -0600
Lisa and the Stevester <stevescott@xxxxxxxxx> wrote:

> Did anyone answer the question?
> It's bore x bore x stroke x 3.14159265
>
>
> >
> > On Nov 30, 2011, at 11:07 AM, "Denis Dodson" <coocoo@xxxxxxx>
> > wrote:
> >
> >     I cannot remember how to figure engine size. I supposedly have a
> >     1904. When I had it built 9 or 10 years ago I was told it was a
> >     1914. It is  74.8 x 88. If I just multiply that I get 6582.4
> > which would mean I have a 6 ½ liter engine and I am pretty sure
> > that is wrong. How do I get to 1914?

```