After two months of waiting, I finally got to dyno my engine. Here is the short list of mods:

351, 11.3 compression, Vicjr heads/intake, and a healty cam. Click here for the complete setup.

   We got started at about 1pm. Due to an oversight on my part, we had to spend 20 minutes removing the inner springs from the heads to break the cam in. At about 2:20, the engine was bolted on, hooked up, and ready to start. For those of you that have never assembled an engine, let me tell you, every time you turn the key for the first time is a religious experience. This engine startup, like the last one, was pretty uneventful. I'd dropped the distributor in, and static timed the engine (you set the balancer at whatever initial timing you want, and line up the star trigger wheel in the distributor with the metal pad on the hall effect switch). The engine died once due to being coldblooded and having a large cam, but the cam breakin went out without a hitch. We then disassembled the valve springs one more time and put the inners back in.

   The first "pull" we did was a cruise test. You set the throttle at 2800 RPM, and set the dyno brake to 30,60,90,and 120 HP. This kind of gives you an idea of what the fuel mix on the carb is doing, and gives you a chance to adjust it.

   The second pull we did was a "checkout" pull. Only ran the motor up to about 5700 RPM, to kind of determine the RPM range of the cam, and to see if anything lets go. So far so good. We did discover a small oil leak from the front pan seal that was spraying some with the balancer whipping by at 6000 RPM. We shielded the spraying oil to keep it from going through the entire dyno room.

   The next 3 or four pulls we determined the optimal timing, each time pulling the engine to 6700 RPM. Let me tell you, that sounds impressive. We discovered that the engine doesn't like much timing (which was what my impression was with this engine the last couple of seasons, even though I had different heads, cam and lower compression). The optimal timing ended up being 31 degrees of total timing.

   Then we bolted on my new Demon carbureter. I broke the motor in on my Holley vacuum secondary carb because it was dialed in. Although a little fat, it worked pretty good, producing 485 HP peak. The first pull with the Demon was cut short when we noticed an alarmingly high A/F ratio of 15:1. Ron (the dyno guy) said that was pretty normal for a Barry Grant/Demon carb out of the box.

   He wanted to get a base line of how much fuel the engine wanted, so he bolted on a "shelf carb", an out of the box Holey HP series 750 DP. This carb has never been apart. Let me tell you, I have new respect for Holley carbureters after this. Not only did this carb idle better than the other two by a large margin, it made more power too. We made the first pull, and the engine made 495 HP. We then tried to add 2 different styles of 1" spacers, and both showed a small loss of power (490 for both). Phew, I don't have to buy a new hood.

   Then, for the last pull, I jetted up the Demon from the factory jetting of 76/83 to 79/88 (numbers suggested by Ron). We bolted on the carb, and made the final pull. When the numbers came up.... 503.9 HP at 6700 RPM!!! Yes, the engine made the magic 500 HP number.

   All in all, a very good day. Nothing blew up or shredded, no major problems, and the motor made the number I was shooting for.

   I can't wait to drop the motor into the car. It's going to feel a little different than last year.

   Here's the quicky curve I punched into Works. My scanner was on the blink, so I couldn't scan the curve from the dyno sheets...

   Anyone in the Minneapolis/St. Paul area, I can't recommend Ron at R & R Performance enough. He definitely knows how to dyno tune an engine.

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