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It was really done because they had carbs rather than fuel injection. Most guys bought the Hilborn fuel injection because it was so simple and easy to tune and adjust that, for instance, you’d go to the drags and this guy would race and say, “How’d you do this round with your Hilborn injection, normally aspirated?” “Well, it was real blubbery and rich off the line, but it cleaned out towards the end of the run and really started to pull.” “What are you going to do, lean it down?” “Yeah, we’re gonna lean it down this run.” So you’d come by an hour earlier. “How’d it do this time?” “Oh, it was clean off the line, but we burned a piston on the top end.” I said you needed two bypasses to adjust the fuel mixture during the run.  So what it was is that the draft in those individual pipes, once you got up above five thousand, there was so much draft in those pipes that it would grab all the wet fuel because the Hilborn was constant flow.

There was about 400° worth of fuel behind that intake valve, so when the overlap period came, it would get swept out the exhaust. Then they’d cruise at the top end instead of pulling real hard. Well with the carburetors you also lost some fuel and air during the high end, but not so much. You didn’t lose 400° worth. Let’s say 722 revolutions is a complete cycle, well you only lost part of that during the overlap period. So that’s what made it charge on the top end, the fact that he had carburetors rather than fuel injection. So that was the five cycle.

: So what was the Polydyne?

EI: The Polydyne. Well we read the technical letters from SAE and someone had come up with the Polydyne formula. In other words, with a rocker arm, push rod, and so forth, there’s some flexibility; they’re not completely rigid. The formula took that into consideration and compensated for the lack of rigidity in the valve train because those parts were, to some extent, flexing. So we started using that formula and that helped us a lot in getting higher RPMs. That was another good publicity stunt.

:  Speaking of publicity, cam wars were a big part of your business and Engle and a lot of the other companies out there. Did that make for better performance? You were always trying to outdo another cam grinder.

EI: Yeah. They claimed that when people picked up Drag News, the first thing they wanted to see was about the fight going on between the cam grinders. It was good for business. The funny thing is that in a way, the development on the cams came not from worrying about the engineering, but just trying something, just seeing what we could get away with. Like, if you went to engineering school, you’d say, “Oh, don’t do that. You’re not supposed to do that. You’re gonna violate some of the principles.” But on the flathead, for instance, it was such a lightweight valvetrain that it could stand a fast action cam. For the overhead valves you needed a softer profile, of course. What it was a lot of ‘cut and try’ involved. I always used to wonder if some engineer was going to shoot me down for some of the things I put in my ads!  Some one that knew their stuff, but there really wasn’t anyone that knew their stuff. No one had that much experience. An engineer, for instance, might work for the automobile factory and he’ll design one cam for one engine in his whole lifetime. It worked okay, it was good enough, and they sold the cars. They didn’t do much experimenting. Instead, they just made the one cam and made a million of ‘em, you know?

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