http://www.summitracing.com/expertadvic ... 828c9ffcce
http://www.summitracing.com/expertadvic ... 828c9ffcce
With high rpm horsepower as the stated goal, a big camshaft was a given for the 388. Trick Flow had just the stick—a Track Max hydraulic roller rated at 246°/254° duration @.050 and .588†lift. With a 3,200-6,800 rpm powerband, the cam is a good complement to the killer airflow available from the Super 23 Race CNC heads. Trick Flow recommends at least 10.4:1 compression and a high stall (3,000-3,500 rpm) torque converter with this cam.
After stabbing in the Track Max camshaft and bolting on the Super 23 Race CNC heads, Trick Flow strapped the new and improved 388 to the dyno. As tested with the Holley/ACCEL EFI setup, the engine made impressive power—533 horsepower at 6,500 rpm and 476 ft.-lbs. of torque at 5,200 rpm. The powerband moved higher as well, which showed that the big cam/big cylinder head idea was working.
Slide 7
The dyno did show the induction system to be an airflow restriction. The main problem was the mismatch between the Holley Stealth Ram and the Super 23 Race CNC heads. The manifold’s ports are too short, and there is not enough material to port-match them to the heads (the fuel injector bungs are in the way). The solution was to swap the EFI for an Edelbrock Super Victor single plane intake and a Holley HP Series 750 double pumper carburetor. The Super Victor has a 3,500-8,500 rpm powerband and an extended runner design that can handle tons of air—darn near ideal for the 388. The port openings have plenty of metal for port-matching, too.
Slide 8
As they say, the third time’s the charm. The 388 with its old school carbureted induction made a righteous 565 horsepower at 6,800 rpm and 485 ft.-lbs. of torque at 5,300 rpm. The engine just kept pulling into the upper reaches of the rpm band, As you can see on the graph, the spread between the horsepower curves of the Edelbrock test and the Holley Stealth Ram test get progressively larger from 6,000 rpm on up. That’s proof the Holley intake was choking high-rpm airflow.
theres a great deal more info here
viewtopic.php?f=69&t=519
http://www.summitracing.com/expertadvic ... 828c9ffcce
With high rpm horsepower as the stated goal, a big camshaft was a given for the 388. Trick Flow had just the stick—a Track Max hydraulic roller rated at 246°/254° duration @.050 and .588†lift. With a 3,200-6,800 rpm powerband, the cam is a good complement to the killer airflow available from the Super 23 Race CNC heads. Trick Flow recommends at least 10.4:1 compression and a high stall (3,000-3,500 rpm) torque converter with this cam.
After stabbing in the Track Max camshaft and bolting on the Super 23 Race CNC heads, Trick Flow strapped the new and improved 388 to the dyno. As tested with the Holley/ACCEL EFI setup, the engine made impressive power—533 horsepower at 6,500 rpm and 476 ft.-lbs. of torque at 5,200 rpm. The powerband moved higher as well, which showed that the big cam/big cylinder head idea was working.
Slide 7
The dyno did show the induction system to be an airflow restriction. The main problem was the mismatch between the Holley Stealth Ram and the Super 23 Race CNC heads. The manifold’s ports are too short, and there is not enough material to port-match them to the heads (the fuel injector bungs are in the way). The solution was to swap the EFI for an Edelbrock Super Victor single plane intake and a Holley HP Series 750 double pumper carburetor. The Super Victor has a 3,500-8,500 rpm powerband and an extended runner design that can handle tons of air—darn near ideal for the 388. The port openings have plenty of metal for port-matching, too.
Slide 8
As they say, the third time’s the charm. The 388 with its old school carbureted induction made a righteous 565 horsepower at 6,800 rpm and 485 ft.-lbs. of torque at 5,300 rpm. The engine just kept pulling into the upper reaches of the rpm band, As you can see on the graph, the spread between the horsepower curves of the Edelbrock test and the Holley Stealth Ram test get progressively larger from 6,000 rpm on up. That’s proof the Holley intake was choking high-rpm airflow.
theres a great deal more info here
viewtopic.php?f=69&t=519