Spring: Baseline Proposed File: Ex Drag Race Spring Ex Drag Race Spring Location: Intake Exhaust Nat Freq (Hz): 363.6 363.6 Installed Force: 501.5 501.5 Spring Rate: 662.4 662.4 Bind Stress, psi: 253570 *2 253570 *2 Cam File: 292-3.DAT 292-3.DAT Spec'd Duration: n/a n/a Spec'd Dur. Lift: n/a n/a Valve Train Type: PushRod w Rocker PushRod w Rocker Follower: Roller Roller Valve Wt, gms: 319 300 Lifter Valve Wt, gms: 410 360 Rocker Ratio: 1.70 1.70 Lash: .028 .028 Follower Diameter: .750 .760 Base Circle: 1.500 1.500 Eff. Valve Wt, gms: 461.3 424.9 Min Rad Curve(nose): .318 .316 Max V Open Accel: .87079 .87079 Max Nose V Accel: -.72269 -.72269 Max V Close Accel: .75048 .75048 Max Valve Lift, in: .54904 .54904 Analysis RPM: 7000 7000 Min Excess Forc,lbs: 23.7 89.8 Required Force, lbs: 838.8 772.7 Safety Factor, %: 2.8 *3 11.6 *3 Seating Vel, in/sec: 3.97 *4 3.97 *4 Lowest Freq Order: 5 5 Lowest Freq RPM: 8730 8730 Harmonics, Spring Nat Freq = 21816 cpm Harmonics, Spring Nat Freq = 21816 cpm # RPM Lift Accel Jerk # RPM Lift Accel Jerk 3 14540 .0831 .7491* 2.2497 3 14540 .0831 .7491* 2.2497 4 10910 .0367 .5857* 2.3426 4 10910 .0367 .5857* 2.3426 5 8730 .0088 .2198* 1.0973 5 8730 .0088 .2198* 1.0973 6 7270 .0013 .0459 .2746 6 7270 .0013 .0459 .2746 7 6230 .0014 .0668 .4648 7 6230 .0014 .0668 .4648 8 5450 .0006 .0401 .3182 8 5450 .0006 .0401 .3182 9 4850 .0008 .0648 .5768 9 4850 .0008 .0648 .5768 10 4360 .0003 .0311 .3060 10 4360 .0003 .0311 .3060 11 3970 .0010 .1196 1.2918 11 3970 .0010 .1196 1.2918 12 3640 .0006 .0817 .9587 12 3640 .0006 .0817 .9587 13 3360 .0003 .0457 .5781 13 3360 .0003 .0457 .5781 14 3120 .0006 .1127 1.5279 14 3120 .0006 .1127 1.5279 15 2910 .0002 .0515 .7449 15 2910 .0002 .0515 .7449 16 2730 .0003 .0588 .9016 16 2730 .0003 .0588 .9016 * Marks Accel Harmonic higher than acceptable for this valve train type. .12 = Limit for Push Rod engines .18 = Limit for OHC Rocker Arm engines .25 = Limit for OHC Direct Acting Bucket engines Baseline: Highest RPM for this spring pack (nat freq 363.6 Hz) is 8730 RPM (Order #5) Proposed: Highest RPM for this spring pack (nat freq 363.6 Hz) is 8730 RPM (Order #5) *2 Bind Stress is the internal stress of the spring wire at coil bind, in pounds per square inch. Even though you may not run the spring to bind, the coils will likely touch in the running engine, producing this bind stress. Levels over 220,000 are higher than in production engines. Levels over 280,000 are for race only, limited hours (like drag racing). *3 Safety Factor indicates how much additional force the spring pack provides above which is required to keep the valve train in contact with the cam. *4 Seating Vel. shows how aggressively the valve is returned to the valve seat. 2.0 = Limit for production vehicles requiring good durability 2.5 = Limit for circle track motors 3.0 = Limit for short run drag race engines Some of these limits come from Don Hubbard's Camshaft Reference Handbook. Because of advances in technology and materials, some of these limits may be lower than what works with modern engines. -- Baseline Spring ---------------- -- Proposed Spring ---------------- RPM Req. Excess Safety Seating Req. Excess Safety Seating Force Force Factor% Velocity Force Force Factor% Velocity 5000 376 505 134.2 2.83 5000 376 505 134.2 2.83 5000 376 505 134.2 2.83 5000 376 505 134.2 2.83 5000 346 548 158.3 3.62 5000 299 553 184.5 3.02 5000 299 553 184.5 3.02 5000 299 553 184.5 3.02 5000 281 471 167.4 4.76 5000 281 471 167.4 4.76 5000 599 263 44.0 2.83 5000 599 263 44.0 2.83 5200 391 490 125.1 2.94 5200 391 490 125.1 2.94 5200 391 490 125.1 2.94 5200 391 490 125.1 2.94 5200 360 534 148.4 3.76 5200 311 541 173.6 3.14 5200 311 541 173.6 3.14 5200 311 541 173.6 3.14 5200 293 460 157.1 4.95 5200 293 460 157.1 4.95 5200 623 239 38.4 2.95 5200 623 239 38.4 2.95 5400 406 475 116.8 3.06 5400 406 475 116.8 3.06 5400 406 475 116.8 3.06 5400 406 475 116.8 3.06 5400 374 520 139.2 3.91 5400 323 529 163.4 3.26 5400 323 529 163.4 3.26 5400 323 529 163.4 3.26 5400 304 449 147.6 5.14 5400 304 449 147.6 5.14 5400 647 215 33.3 3.06 5400 647 215 33.3 3.06 5600 421 460 109.1 3.17 5600 421 460 109.1 3.17 5600 421 460 109.1 3.17 5600 421 460 109.1 3.17 5600 388 506 130.7 4.05 5600 335 517 154.0 3.38 5600 335 517 154.0 3.38 5600 335 517 154.0 3.38 5600 315 437 138.8 5.33 5600 315 437 138.8 5.33 5600 671 191 28.5 3.18 5600 671 191 28.5 3.18 5800 436 444 101.9 3.28 5800 436 444 101.9 3.28 5800 436 444 101.9 3.28 5800 436 444 101.9 3.28 5800 401 492 122.7 4.20 5800 347 505 145.3 3.50 5800 347 505 145.3 3.50 5800 347 505 145.3 3.50 5800 327 426 130.5 5.52 5800 327 426 130.5 5.52 5800 695 167 24.1 3.29 5800 695 167 24.1 3.29 6000 451 429 95.1 3.40 6000 451 429 95.1 3.40 6000 451 429 95.1 3.40 6000 451 429 95.1 3.40 6000 415 479 115.3 4.34 6000 359 493 137.1 3.62 6000 359 493 137.1 3.62 6000 359 493 137.1 3.62 6000 338 415 122.8 5.71 6000 338 415 122.8 5.71 6000 719 144 20.0 3.40 6000 719 144 20.0 3.40 6200 466 414 88.8 3.51 6200 466 414 88.8 3.51 6200 466 414 88.8 3.51 6200 466 414 88.8 3.51 6200 429 465 108.3 4.49 6200 371 481 129.4 3.74 6200 371 481 129.4 3.74 6200 371 481 129.4 3.74 6200 349 404 115.6 5.90 6200 349 404 115.6 5.90 6200 743 120 16.1 3.52 6200 743 120 16.1 3.52 6400 482 399 82.9 3.62 6400 482 399 82.9 3.62 6400 482 399 82.9 3.62 6400 482 399 82.9 3.62 6400 443 451 101.8 4.63 6400 383 469 122.3 3.86 6400 383 469 122.3 3.86 6400 383 469 122.3 3.86 6400 360 392 108.9 6.09 6400 360 392 108.9 6.09 6400 767 96 12.5 3.63 6400 767 96 12.5 3.63 6600 497 384 77.4 3.73 6600 497 384 77.4 3.73 6600 497 384 77.4 3.73 6600 497 384 77.4 3.73 6600 457 437 95.7 4.78 6600 395 457 115.5 3.98 6600 395 457 115.5 3.98 6600 395 457 115.5 3.98 6600 372 381 102.6 6.28 6600 372 381 102.6 6.28 6600 791 72 9.1 3.74 6600 791 72 9.1 3.74 6800 512 369 72.2 3.85 6800 512 369 72.2 3.85 6800 512 369 72.2 3.85 6800 512 369 72.2 3.85 6800 471 423 90.0 4.92 6800 407 445 109.2 4.10 6800 407 445 109.2 4.10 6800 407 445 109.2 4.10 6800 383 370 96.6 6.47 6800 383 370 96.6 6.47 6800 815 48 5.9 3.86 6800 815 48 5.9 3.86 7000 527 354 67.3 3.96 7000 527 354 67.3 3.96 7000 527 354 67.3 3.96 7000 527 354 67.3 3.96 7000 484 409 84.5 5.07 7000 419 433 103.2 4.23 7000 419 433 103.2 4.23 7000 419 433 103.2 4.23 7000 394 359 91.0 6.67 7000 394 359 91.0 6.67 7000 839 24 2.8 3.97 7000 839 24 2.8 3.97 7200 542 339 62.6 4.07 7200 542 339 62.6 4.07 7200 542 339 62.6 4.07 7200 542 339 62.6 4.07 7200 498 396 79.4 5.21 7200 431 421 97.6 4.35 7200 431 421 97.6 4.35 7200 431 421 97.6 4.35 7200 405 347 85.7 6.86 7200 405 347 85.7 6.86 7200 863 0 0.0 4.08 7200 863 0 0.0 4.08 7400 557 324 58.2 4.19 7400 557 324 58.2 4.19 7400 557 324 58.2 4.19 7400 557 324 58.2 4.19 7400 512 382 74.6 5.36 7400 443 409 92.2 4.47 7400 443 409 92.2 4.47 7400 443 409 92.2 4.47 7400 417 336 80.7 7.05 7400 417 336 80.7 7.05 7400 887 -24 -2.7 4.20 7400 887 -24 -2.7 4.20 7600 572 309 54.0 4.30 7600 572 309 54.0 4.30 7600 572 309 54.0 4.30 7600 572 309 54.0 4.30 7600 526 368 70.0 5.50 7600 455 397 87.2 4.59 7600 455 397 87.2 4.59 7600 455 397 87.2 4.59 7600 428 325 75.9 7.24 7600 428 325 75.9 7.24 7600 911 -48 -5.3 4.31 7600 911 -48 -5.3 4.31 7800 587 294 50.1 4.41 7800 587 294 50.1 4.41 7800 587 294 50.1 4.41 7800 587 294 50.1 4.41 7800 540 354 65.6 5.64 7800 467 385 82.4 4.71 7800 467 385 82.4 4.71 7800 467 385 82.4 4.71 7800 439 314 71.4 7.43 7800 439 314 71.4 7.43 7800 935 -72 -7.7 4.42 7800 935 -72 -7.7 4.42 8000 602 279 46.3 4.53 8000 602 279 46.3 4.53 8000 602 279 46.3 4.53 8000 602 279 46.3 4.53 8000 554 340 61.5 5.79 8000 479 373 77.8 4.83 8000 479 373 77.8 4.83 8000 479 373 77.8 4.83 8000 450 302 67.1 7.62 8000 450 302 67.1 7.62 8000 959 -96 -10.0 4.54 8000 959 -96 -10.0 4.54 8200 617 264 42.8 4.64 8200 617 264 42.8 4.64 8200 617 264 42.8 4.64 8200 617 264 42.8 4.64 8200 567 326 57.5 5.93 8200 491 361 73.5 4.95 8200 491 361 73.5 4.95 8200 491 361 73.5 4.95 8200 462 291 63.1 7.81 8200 462 291 63.1 7.81 8200 983 -120 -12.2 4.65 8200 983 -120 -12.2 4.65 8400 632 249 39.4 4.75 8400 632 249 39.4 4.75 8400 632 249 39.4 4.75 8400 632 249 39.4 4.75 8400 581 313 53.8 6.08 8400 503 349 69.3 5.07 8400 503 349 69.3 5.07 8400 503 349 69.3 5.07 8400 473 280 59.2 8.00 8400 473 280 59.2 8.00 8400 1007 -144 -14.3 4.76 8400 1007 -144 -14.3 4.76 8600 647 234 36.1 4.87 8600 647 234 36.1 4.87 8600 647 234 36.1 4.87 8600 647 234 36.1 4.87 8600 595 299 50.2 6.22 8600 515 337 65.4 5.19 8600 515 337 65.4 5.19 8600 515 337 65.4 5.19 8600 484 269 55.5 8.19 8600 484 269 55.5 8.19 8600 1031 -168 -16.3 4.88 8600 1031 -168 -16.3 4.88 8800 662 219 33.0 4.98 8800 662 219 33.0 4.98 8800 662 219 33.0 4.98 8800 662 219 33.0 4.98 8800 609 285 46.8 6.37 8800 527 325 61.7 5.31 8800 527 325 61.7 5.31 8800 527 325 61.7 5.31 8800 495 257 51.9 8.38 8800 495 257 51.9 8.38 8800 1054 -192 -18.2 4.99 8800 1054 -192 -18.2 4.99 9000 677 204 30.1 5.09 9000 677 204 30.1 5.09 9000 677 204 30.1 5.09 9000 677 204 30.1 5.09 9000 623 271 43.5 6.51 9000 539 313 58.1 5.43 9000 539 313 58.1 5.43 9000 539 313 58.1 5.43 9000 507 246 48.6 8.57 9000 507 246 48.6 8.57 9000 1078 -216 -20.0 5.10 9000 1078 -216 -20.0 5.10