Pre-heating a racing engine increases its power and reduces engine failures. This subject may sound like there are easy answers to conclude but this is not exactly the case. Let’s take the first claim, that is, hot engines make more power. When we explore the extreme cases of very hot and extremely cold the answer is simply yes, so this means that there is an exact temperature that is optimum for getting the most power from your racing engine. I’ve traveled to a hundred races and have had engaging conversations with pit full’s of racers, crew chiefs and engine builders. An impressionable statement came from a very credible professional KTM motocross rider that wouldn’t back down from his claim that his engine made more power off the starting gate when it was cold. I was curious about the claim so I spoke with a top engine builder who laughed and agreed that yes it probably did. He went on to explain that improper engine tuning can cause an engine to make its peak power at a lower temperature, then fade a bit when it gets fully heated. So the rider was probably right but giving up additional power to be had through proper tuning. Research indicates that cylinder wall and combustion chamber surface temperatures need to be at least 180 degrees F. This is the minimum operating temperature where ideal air and fuel charge combustion efficiency is achieved.
Now let’s go back to the race track again, this time we are at the Top fuel Nationals at Infineon raceway in Sonoma CA.