[Cliff R]

Here are the dyno runs from the two cams. I condensed them to one page for easier comparison.

What I left out of all of this is that the dyno shop that built the engine tried to crank up the timing and swapped carbs around in order to try to make acceptable power.

They "pinged" the engine on the dyno after this pull was made and ended up taking out the rod bearings and bent the crank .020"!

The pulls shown were the best pulls made in each configuration. The intake manifold used for the testing was the Edelbrock RPM intake. During the first session they thought at first the problems were due to the custom built Q-jet carburetor that was supplied for the engine, so they side-lined the carb and made all pulls with their Holley 830cfm "dyno carb".

The q-jet wasn't built here, but it ended up getting sent here for us to check it out and run it on one of our engines to make sure it was fine before putting it back in service, which we did.

The peak numbers from the two dyno runs really don't tell the whole story here. The "tiny" HR cam was WAY too good at cylinder filling with the 250cfm heads, even though the compression ratio was under the often recommended threshold of 9.5 to 1. I've seen this before with this exact same engine/cam combo. That cam is WAY too good at cylinder filling early in the rpm range, and makes a low compression engine want a LOT more octane to be happy.

This engine was professionally built with very good flowing heads. Notice how it really shined when they installed a cam that was more suited to what they were doing. What one really needs to look at instead of "peak" numbers, is how much power (torque) the engine enjoyed with the bigger cam across the upper mid-range and top end. It also idled better and made a BUTT LOAD more average power.

This type of engine is very good at moving these heavy cars around without a lot of gearing or converter, and there is no need to run it WAY up in the rpm range to make good track runs. You can shift down around 5000 rpms and still run nearly as well as shifting clear up at 5900rpm's where peak power was made at, just look at how much torque it's making in the upper mid-range. This engine wouldn't care where you shifted at, it would continue to pull like a locomotive everyplace.......Cliff