Calculated Industries 8703 - Manual (Page 47)

H
OT
R
OD
C
ALC
™ — 45
BDC TDC
There are several compression ratio effects to consider when
determining the appropriate ratio for your application:
• The greater the compression ratio, the greater the amount of air/
fuel mix will be compressed.
• The greater amount of air/fuel mix that is compressed, the greater
the combustion power will be.
• The greater the combustion power is, the hotter the combustion is
which can lead to detonation.
• Detonation (pinging and knocking) can be resolved by using
higher octane fuel (at a higher cost, of course) and/or a change in
ignition timing curve.
So, to get big power, you need big compression ratios to get more
powerful combustion, which requires higher octane fuels.