I'm not real old, but I'm old enough to remember the very basic rules to build the best, most powerful engine one can build is to do everything possible to the utmost to make the engine as perfect as one can make it. To me, this means polishing ALL ports. When I was a kid, polishing and relieving was a major step in building engines.....and the engines they were building then were 235's, 261's and flatties.
Why would the professional's rules change if the engine hasn't changed? I think the answer is in your thoughts. It needs to be done, THAN and only than you won't have to ask "what if?"
Joe
Hello sir, I don't believe that the rules have actually changed as much as its the "techniques" in how its done have become refined and improved. It's true that back before many hotrodders had access to flowbenchs, the popular thought of that time was that smoother was better when it came to relieving and porting. Probably because the only gage for this thinking was your index finger rubbing across the ports of a head or intake, and they just convinced themselves that a rougher finish had to create drag or some other unacceptable issue! True, even slick finishes on intake ports still produced more HP because the port was "ported" as well. The difference between a "polished" port and a "rough" finish in the intake tract probably is miniscule on a dyno. But the improvements in fuel atomization helps promote better and more complete and consistant burning of gases. If you don't burn 100%(or close to it) of the gas that enters the cylinders, then you begin to have a break down in efficiency. Fouled plugs, wash out cylinders....if you are racing, you find yourself following instead of leading the race! Head porting technology has probably improved at a faster rate than any other technology in the racing industry. Partly because so much gain can be gotten in terms of HP. And in 10 years, it will be so far advanced from where it is now....Just as in the day of polished ports, it still worked, you still could tell you made increases in power,technology improved and you moved forward and here we are 30 or 40 years later, still improving and advancing!
