Experiences while bending the rules…

While I don’t recall my age at the time, I vividly remember my first trip down a dragstrip.  It was in south central Texas, just outside my home in Austin, and it was a dirt track.  In fact, it was the main straight of a one-and-a-half-mile horse racing oval.  While traction was a bit problematic, it was the gradual left-hand turn in the shut-down area that tended to pucker your butt a bit.  Nevertheless, it was all we had and it was a well-used facility.  Of course the starting line “equipment” consisted of a flagman, often favoring the locals to the chagrin of participants outside the immediate Austin area.  Frankly, this aspect was about the same whether you were racing on the outskirts of Austin or on the storied strip in Santa Ana, California.  As you might imagine, tech inspection was marginal at best, thereby giving rise to young budding drag racers maybe attempting a bit of rules bending.

At that stage in the evolution of drag racing, checking engines for valid piston displacement involved removing a cylinder head and physically measuring bore and stroke.  “Pumping” an engine was decades away, as you’ll note later.   So after observing this procedure for a time and recognizing it was typically practice to remove the most convenient head (notably for V-type engines), an idea came to mind.  If the brake master cylinder, particularly in cars with a large vacuum-assisted booster, made removal of the driver-side head more of a chore than on the passenger-side, how might this be an opportunity?  We took two approaches.

Approach #1 was to bore out the cylinders on the driver’s side of the block.  In this particular case, the engine was a 265-inch small-block Chevy that would easily allow a bore increase of 0.125-inch.  So that’s what we did.  We hadn’t thought about grinding camshafts to favor the driver-side bank of cylinders.  That came later.  Several back-to-back weekend wins and failure of the “tech” inspector to uncover our method aroused the “stock class” competition to register a protest and observe the inspection first-hand.  To this day, I believe the machine shop we’d used leaked our secret and we were discovered.  So we forfeited that particular win and went back to the rule bending drawing board.

Approach #2 turned out to be more effective.  Since the tech inspection procedure didn’t then involve combustion chamber volume measurement, and because our tech inspector was now zeroed in on removing the driver’s side head, we chose to shave 0.030-inches off the passenger-side head.  Keep in mind that on a dirt track where a simple miscalculation in starting-line technique could erase any potential benefits from slight power gains, the psychological impact of “thinking” we had an advantage probably did more for winning races than our rule-bending changes.  And, if memory serves, it took the tech guy about a half-dozen races to discover approach #2.

At any rate, because of problems obvious to drag racing on a dirt track, our little band of racers decided to venture into local circle track racing, still of the same “if the rules don’t say you can’t do it” mind set.  One of our group of renegade racers had a father teaching college-level organic chemistry.  He was a natural source for our questions about how to disguise power-enhancing and undetectable fuel additives.  Our choice focused on hydrazine and its properties during combustion in an engine.  Somebody had said it was used in rocket fuel.  Innocence is bliss.

Since my bent was mechanical engineering and not chemistry, I’d not realized the potential dangers involved with this chemical, particularly its instability, even in liquid form.

After befriending one of the local “hot shoes” at the most popular dirt circle track in the area, we gained an opportunity to “experiment” with the fuel he was using.  It’s worth noting that his engine of choice (at the time) was a multi-carburetor, flat-head Ford.  He already held the track qualifying record and had notched a number of feature wins during that particular season.  Those familiar with these engines will recall the oil filler (and breather) tube was essentially a vertical tube located near the rear of the engine.  Remember that.