Individual cylinder timing could make nitro engines more reliable

Timing is everything especially for nitro burning engines

Words by Jeff Burk
Photos by Jeff Burk and courtesy MSD

For the last 60 years the horsepower developed by an NHRA Top Fuel or Funny Car nitro engine has increased on a geometric progression, from around 1,500-2000 hp in the 1960's to the 8,000-10,000 estimated hp today's engines develop. Also, for the last 60 years nitro motors have been exploding. Tuning one of these engines that's uses a fuel mixture of Nitromethane and alcohol so it doesn't explode every time the throttle is moved is a daunting task at best.

That steady improvement of engine performance has resulted in increased engine failures that have substantially skyrocketed the cost for NHRA pro nitro engine programs. The fact that most NHRA nitro teams bring enough complete engines to each race to install a new engine after every lap is an indication of how fragile the nitro engine has become.

In an effort to increase the reliability of nitro engine and the "consumable" parts like blocks, heads, crankshafts, rods and pistons and superchargers the designs are much improved and are mostly machined from big billets of aluminum. Points style 10-amp mags have been replaced by programmable 44-amp electronic ignition systems, 100+ gph fuel pumps and six-disc clutches. Tuners of nitro engines need as many tuning aids and procedures as they can get to help them prevent catastrophic engine failures while improving engine reliability and performance.