one for Russellw

[parawolf]

Love your work by the way Russ... However I just noticed in a tech doc an inconsistancy... I assume its meant to be 0.166 all the way through?

The formula for calculating piston speed is simply 0.166 x stroke (in inches) x RPM
To convert a stroke in millimetres into inches simply multiply the mm by 0.03937.

Let us look at a worked example.

1. The Boss 290 has a bore/stroke of 90.2 x 105.8 mm.
SO we multiply 105.8 x 0.03937 to arrive at 4.1653 inches
The maximum RPM is 5500.

Applying the formula we have .0166 x 4.1653 x 5500 which equals 3802.9 feet per min.
If you are metricated you can divide that result by 197.04 to arrive at metres per second = 19.3 m/s.

2. The Mustang 4.6 DOHC engine has a bore/stroke of 90.2 x 90.0 and max RPM of 6000.
we therefore multiply 90.0 x 0.03937 to arrive at 3.5443 inches
therefore: 0.166 x 3.5443 x 6000 = 3529 fpm or 17.91 m/s.

[russellw]

Well spotted thanks. It should indeed be 0.166 consistently. I shall amend it accordingly.

Cheers
Russ