Technology

Excerpt from Mike Kostic writing in
FLAT OUT Magazine

In a storage drawer in my workshop is a three hole binder full of dyno sheets. Most of these came from running the motors I build on Don Ott’s dyno out in York Springs, PA. These sheets show that the water temperature maintained for all Don’s pulls are 200 to 205 degrees F. This is the temperature target for both iron block 360 cubic inch URC engines and Brodix aluminum 410s. This ought to tell you what a good operating temperature is for both horsepower development and race engine longevity.

Sprint car engines use constant flow fuel injection systems and methanol. This combination insures a fuel dense cylinder charge. It takes a good amount of heat to completely vaporize this type of mixture. Not only does putting stress on a cold engine shorten its life span, if the water temp gauge is sitting below 160 degrees when the green flag drops, the car just does not take off.

So how do we get a race engine up to correct operating temperature before we put it under load? Tradition for sprint cars and other non starter motor open wheel cars is the call for “Heat in the Motors” Depending on the track this can involve pushing off a cold engine out on the racing surface followed by putting the cold, fuel rich engine under load long enough to drive back to the pits. Not wonderful treatment for high dollar race motors. Once back in the pit stall the engine has to sit with fuel shut off valve closed enough to lean out the motor to reduce cylinder wash down until it gets up to 180 degrees. This takes some time, and burns up some fuel. Methanol has doubled in cost in the last three years. But before we feel to sorry for ourselves, our late model racing brothers are paying over $8.00 a gallon for their go juice.

Back in the day, we used kerosene space heaters pointed at the side of the engine and oil tank. Not very efficient, and unless carefully monitored, space heaters can overheat and damage various fluid lines, fiberglass hoods and other parts not intended to be preheated. I’ve proved that it is possible to overheat a steel brake line while heating up an engine to the point where the front brake locked up in the pits.

Today’s racers have a better option, the HotHead Competition Engine Heater from Hot Products Engineering. Their offering can best be described as a constant flow inline heater. Two heating elements of the type used to preheat truck engines and a circulating pump are housed in a compact aluminum diamond plate tool box. Two 8 foot long hoses with female Aeroquip quick connect fittings link the heater to the engine. The control panel has a temperature gauge, two circuit breakers and a selector switch that energizes both heating elements and the pump to preheat the engine or one heating element and the pump to maintain temperature. A Hot Products heater will set you back $1250.

The Hot Head unit comes pre-wired for either one 220 V or two 115V power connections. The most popular set up is the 220 V deal. The Hot Head can be purchased with either two 1500 watt or two 2000 watt heating elements. This power requirements needs considering when matching the heater to the generator.

The Hot Head we tested heated an iron block 360 to 190 degrees F in less than 30 minutes in 50 degree fall weather. If you cruse the pits in Central PA you will see a lot of Hot Heads, engine heaters that is.

How do we connect the heater to our engine? Hot Head offers a manifold that is installed into the lower radiator hose. There is a one way flapper valve installed between the inlet and the outlet connections.

See ya at the races.