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Time to try another intake. We had previously posted on Classical Pontiac and Performance Years about our intended testing and asked if anyone would lend us a Performer RPM to test along with our other intakes. Glenn Tandy came through and sent us his RPM to test along with our Torker II and Hurricane. First pull with the RPM was way rich. Power was down and BSFC numbers were up. Unfortunately, after 20 pulls the engine started knocking. That was it for this session.

We tore apart the engine the next day and found a spun rod bearing and a scored #2 main bearing. I believe the combination of the stock tight bearing clearances and the higher than anticipated rpm levels were too much for our short block. We changed the rod, polished the crank and honed the rod big ends along with the main saddles for a little more clearance. We ended up with 0.0025" on the rods and 0.003" for the mains. At the same time, we decided to advance the cam 2° to an installed intake centerline of 106°. We hoped that would bring our horsepower peak down by a few hundred rpm.

Back at the dyno for another session, we started where we left off with the RPM intake. After a few pulls to optimize the combination, we had 584 HP and 609 lb-ft. Peak power was about the same but the power under 4800 rpm was quite a bit higher, with as much as 50 lb-ft more at 3900 rpm than the Torker II or the Hurricane that was next to be tested. Definitely the better choice for a street or street/strip car.

We tried the Hurricane with a ½" wood spacer, no spacer, and 1" Supersucker. We settled on the ½" wood spacer as what we would run on the car.

The last 10 pulls were made with 1 7/8" Hedman Hustler Hedders borrowed from Tony (who was building a similar engine for his '74 Trans Am). The 1 7/8" headers were worth an average of 18 HP and 16 lb-ft over the Hooker 1 ¾" Super Comps.

That was it for our testing on the dyno. The next round will be at the track this summer.

Many thanks to Nick, Philipp and everyone at Panaritis Automotive for all their help.

I pulled the oil pan and checked a couple of rod bearings as well as the #2 main bearing a few weeks later and everything was like new (phew!). At that time I installed an 80 lb spring (replacing the 60 lb) in the oil pump because during all the dyno pulls the oil pressure was only going as high as 40-45 psi. I think the vacuum pump might have had something to do with the lower observed oil pressures.