Power By The NumbersTest 1 consisted of the 383 small-block Chevy with the flat-tappet hydraulic Comp XE284 cam. All other components for this test remained the same for all three tests.
Test 2 changed to the XEHR294 hydraulic roller cam and dual valvesprings.
Test 3 swapped to the XR286 mechanical roller cam and to a third, higher-load set of dual valvesprings with titanium retainers.
Before bolting the engine...
Before bolting the engine on the dyno, we also took the time to check for roller cam endplay for both the mechanical and hydraulic roller cams to ensure neither cam would move forward and retard the ignition timing. We used this Comp Cams three-piece small-block Chevy timing cover to make the cam swaps easy. It also features an access hole for measuring cam endplay.
The DIFF column represents the difference in power between Test 1 and Test 3.
| | TEST 1 | TEST 2 | TEST 3 | DIFF |
| RPM | TQ | HP | TQ | HP | TQ | HP | TQ | HP |
| 3,000 | 420 | 240 | 421 | 241 | 425 | 243 | +5 | +3 |
| 3,200 | 429 | 262 | 429 | 262 | 431 | 263 | +2 | +1 |
| 3,400 | 430 | 279 | 430 | 278 | 434 | 281 | +4 | +2 |
| 3,600 | 436 | 299 | 438 | 300 | 437 | 300 | + 1 | +1 |
| 3,800 | 441 | 319 | 445 | 322 | 445 | 322 | +4 | +3 |
| 4,000 | 448 | 341 | 446 | 340 | 446 | 340 | - 2 | - 1 |
| 4,200 | 460 | 368 | 460 | 368 | 462 | 370 | +2 | +2 |
| 4,400 | 465 | 390 | 467 | 391 | 472 | 395 | +7 | +5 |
| 4,600 | 477 | 418 | 476 | 417 | 481 | 422 | +4 | +4 |
| 4,800 | 487 | 446 | 491 | 449 | 489 | 447 | +2 | +1 |
| 5,000 | 489 | 466 | 500 | 476 | 494 | 470 | +5 | +4 |
| 5,200 | 489 | 485 | 502 | 497 | 496 | 491 | +7 | +6 |
| 5,400 | 482 | 495 | 496 | 510 | 493 | 507 | +11 | +12 |
| 5,600 | 467 | 498 | 487 | 519 | 486 | 518 | +19 | +20 |
| 5,800 | 456 | 503 | 478 | 528 | 476 | 526 | +20 | +23 |
| 6,000 | 443 | 506 | 463 | 529 | 464 | 530 | +21 | +24 |
| 6,200 | 429 | 507 | 449 | 530 | 452 | 534 | +23 | +27 |
| 6,400 | 409 | 499 | 431 | 525 | 442 | 539 | +33 | +40 |
| 6,600 | 378 | 475 | 415 | 522 | 429 | 539 | +51 | +64 |
| Avg. | 450.7 | 412 | 460.7 | 423 | 461.7 | 424 | +11 | +12 |
| Peak | 489 | 507 | 502 | 530 | 496 | 539 | +7 | +32 |
Note: The average columns take into account power numbers every 100 rpm, which are not listed in this chart.