How much does your 7M breath under boost?

starscream5000

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#1
The following are calculations figured up using these links:
http://www.mygen.com/users/dbruce/m...Engine Air Flow and Turbo Compressor Maps.htm

http://not2fast.com/turbo/glossary/turbo_calc.shtml

These numbers are set in increments of 250 RPMs starting at 2500 RPMs and ending at 7500 (for those people who are running higher than the stock rev limit).

The first column of course is the RPM's, the second column is flow (in CFMs) for a NON-TURBO supra, third is flow (again, in CFM's) for the TURBO supra, and the last is a translation of column 3 into lb/min.

10 psi (1.68027210884)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- STOCK BORE ENGINE
---------- 180Cid -------- 1.680272109 ----- 14.472



2500 ---- 104.1666667 ---- 175.0283447 ---- 12.09427478
2750 ---- 114.5833333 ---- 192.5311791 ---- 13.30370226
3000 ---- 125.0000000 ---- 210.0340136 ---- 14.51312974
3250 ---- 135.4166667 ---- 227.5368481 ---- 15.72255722
3500 ---- 145.8333333 ---- 245.0396825 ---- 16.9319847
3750 ---- 156.2500000 ---- 262.5425170 ---- 18.14141218
4000 ---- 166.6666667 ---- 280.0453515 ---- 19.35083965
4250 ---- 177.0833333 ---- 297.5481859 ---- 20.56026713
4500 ---- 187.5000000 ---- 315.0510204 ---- 21.76969461
4750 ---- 197.9166667 ---- 332.5538549 ---- 22.97912209
5000 ---- 208.3333333 ---- 350.0566893 ---- 24.18854957
5250 ---- 218.7500000 ---- 367.5595238 ---- 25.39797705
5500 ---- 229.1666667 ---- 385.0623583 ---- 26.60740452
5750 ---- 239.5833333 ---- 402.5651927 ---- 27.816832
6000 ---- 250.0000000 ---- 420.0680272 ---- 29.02625948
6250 ---- 260.4166667 ---- 437.5708617 ---- 30.23568696
6500 ---- 270.8333333 ---- 455.0736961 ---- 31.44511444
6750 ---- 281.2500000 ---- 472.5765306 ---- 32.65454192
7000 ---- 291.6666667 ---- 490.0793651 ---- 33.86396939
7250 ---- 302.0833333 ---- 507.5821995 ---- 35.07339687
7500 ---- 312.5000000 ---- 525.0850340 ---- 36.28282435



13psi (1.88435374149)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- STOCK BORE ENGINE
---------- 180Cid -------- 1.884353741 ----- 14.472



2500 ---- 104.1666667 ---- 196.2868481 ---- 13.56321504
2750 ---- 114.5833333 ---- 215.9155329 ---- 14.91953654
3000 ---- 125.0000000 ---- 235.5442177 ---- 16.27585805
3250 ---- 135.4166667 ---- 255.1729025 ---- 17.63217955
3500 ---- 145.8333333 ---- 274.8015873 ---- 18.98850106
3750 ---- 156.2500000 ---- 294.4302721 ---- 20.34482256
4000 ---- 166.6666667 ---- 314.0589569 ---- 21.70114407
4250 ---- 177.0833333 ---- 333.6876417 ---- 23.05746557
4500 ---- 187.5000000 ---- 353.3163265 ---- 24.41378707
4750 ---- 197.9166667 ---- 372.9450113 ---- 25.77010858
5000 ---- 208.3333333 ---- 392.5736961 ---- 27.12643008
5250 ---- 218.7500000 ---- 412.2023810 ---- 28.48275159
5500 ---- 229.1666667 ---- 431.8310658 ---- 29.83907309
5750 ---- 239.5833333 ---- 451.4597506 ---- 31.19539459
6000 ---- 250.0000000 ---- 471.0884354 ---- 32.5517161
6250 ---- 260.4166667 ---- 490.7171202 ---- 33.9080376
6500 ---- 270.8333333 ---- 510.3458050 ---- 35.26435911
6750 ---- 281.2500000 ---- 529.9744898 ---- 36.62068061
7000 ---- 291.6666667 ---- 549.6031746 ---- 37.97700211
7250 ---- 302.0833333 ---- 569.2318594 ---- 39.33332362
7500 ---- 312.5000000 ---- 588.8605442 ---- 40.68964512



15psi (2.02040816326)



RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- STOCK BORE ENGINE
---------- 180Cid -------- 2.020408163 ----- 14.472



2500 ---- 104.1666667 ---- 210.4591837 ---- 14.54250855
2750 ---- 114.5833333 ---- 231.5051020 ---- 15.9967594
3000 ---- 125.0000000 ---- 252.5510204 ---- 17.45101025
3250 ---- 135.4166667 ---- 273.5969388 ---- 18.90526111
3500 ---- 145.8333333 ---- 294.6428571 ---- 20.35951196
3750 ---- 156.2500000 ---- 315.6887755 ---- 21.81376282
4000 ---- 166.6666667 ---- 336.7346939 ---- 23.26801367
4250 ---- 177.0833333 ---- 357.7806122 ---- 24.72226453
4500 ---- 187.5000000 ---- 378.8265306 ---- 26.17651538
4750 ---- 197.9166667 ---- 399.8724490 ---- 27.63076624
5000 ---- 208.3333333 ---- 420.9183673 ---- 29.08501709
5250 ---- 218.7500000 ---- 441.9642857 ---- 30.53926795
5500 ---- 229.1666667 ---- 463.0102041 ---- 31.9935188
5750 ---- 239.5833333 ---- 484.0561224 ---- 33.44776966
6000 ---- 250.0000000 ---- 505.1020408 ---- 34.90202051
6250 ---- 260.4166667 ---- 526.1479592 ---- 36.35627136
6500 ---- 270.8333333 ---- 547.1938775 ---- 37.81052222
6750 ---- 281.2500000 ---- 568.2397959 ---- 39.26477307
7000 ---- 291.6666667 ---- 589.2857143 ---- 40.71902393
7250 ---- 302.0833333 ---- 610.3316327 ---- 42.17327478
7500 ---- 312.5000000 ---- 631.3775510 ---- 43.62752564


18psi (2.22448979591)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- STOCK BORE ENGINE
---------- 180Cid -------- 2.224489796 ----- 14.472



2500 ---- 104.1666667 ---- 231.7176871 ---- 16.0114488
2750 ---- 114.5833333 ---- 254.8894558 ---- 17.61259368
3000 ---- 125.0000000 ---- 278.0612245 ---- 19.21373856
3250 ---- 135.4166667 ---- 301.2329932 ---- 20.81488344
3500 ---- 145.8333333 ---- 324.4047619 ---- 22.41602832
3750 ---- 156.2500000 ---- 347.5765306 ---- 24.0171732
4000 ---- 166.6666667 ---- 370.7482993 ---- 25.61831808
4250 ---- 177.0833333 ---- 393.9200680 ---- 27.21946296
4500 ---- 187.5000000 ---- 417.0918367 ---- 28.82060785
4750 ---- 197.9166667 ---- 440.2636054 ---- 30.42175273
5000 ---- 208.3333333 ---- 463.4353741 ---- 32.02289761
5250 ---- 218.7500000 ---- 486.6071429 ---- 33.62404249
5500 ---- 229.1666667 ---- 509.7789116 ---- 35.22518737
5750 ---- 239.5833333 ---- 532.9506803 ---- 36.82633225
6000 ---- 250.0000000 ---- 556.1224490 ---- 38.42747713
6250 ---- 260.4166667 ---- 579.2942177 ---- 40.02862201
6500 ---- 270.8333333 ---- 602.4659864 ---- 41.62976689
6750 ---- 281.2500000 ---- 625.6377551 ---- 43.23091177
7000 ---- 291.6666667 ---- 648.8095238 ---- 44.83205665
7250 ---- 302.0833333 ---- 671.9812925 ---- 46.43320153
7500 ---- 312.5000000 ---- 695.1530612 ---- 48.03434641


20psi (2.36054421768)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- STOCK BORE ENGINE
---------- 180Cid -------- 2.360544218 ----- 14.472



2500 ---- 104.1666667 ---- 245.8900227 ---- 16.99074231
2750 ---- 114.5833333 ---- 270.4790249 ---- 18.68981654
3000 ---- 125.0000000 ---- 295.0680272 ---- 20.38889077
3250 ---- 135.4166667 ---- 319.6570295 ---- 22.087965
3500 ---- 145.8333333 ---- 344.2460317 ---- 23.78703923
3750 ---- 156.2500000 ---- 368.8350340 ---- 25.48611346
4000 ---- 166.6666667 ---- 393.4240363 ---- 27.18518769
4250 ---- 177.0833333 ---- 418.0130385 ---- 28.88426192
4500 ---- 187.5000000 ---- 442.6020408 ---- 30.58333615
4750 ---- 197.9166667 ---- 467.1910431 ---- 32.28241038
5000 ---- 208.3333333 ---- 491.7800454 ---- 33.98148462
5250 ---- 218.7500000 ---- 516.3690476 ---- 35.68055885
5500 ---- 229.1666667 ---- 540.9580499 ---- 37.37963308
5750 ---- 239.5833333 ---- 565.5470522 ---- 39.07870731
6000 ---- 250.0000000 ---- 590.1360544 ---- 40.77778154
6250 ---- 260.4166667 ---- 614.7250567 ---- 42.47685577
6500 ---- 270.8333333 ---- 639.3140590 ---- 44.17593
6750 ---- 281.2500000 ---- 663.9030612 ---- 45.87500423
7000 ---- 291.6666667 ---- 688.4920635 ---- 47.57407846
7250 ---- 302.0833333 ---- 713.0810658 ---- 49.27315269
7500 ---- 312.5000000 ---- 737.6700680 ---- 50.97222692


23psi (2.56462585034)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- STOCK BORE ENGINE
---------- 180Cid -------- 2.56462585 ----- 14.472



2500 ---- 104.1666667 ---- 267.1485261 ---- 18.45968256
2750 ---- 114.5833333 ---- 293.8633787 ---- 20.30565082
3000 ---- 125.0000000 ---- 320.5782313 ---- 22.15161908
3250 ---- 135.4166667 ---- 347.2930839 ---- 23.99758733
3500 ---- 145.8333333 ---- 374.0079365 ---- 25.84355559
3750 ---- 156.2500000 ---- 400.7227891 ---- 27.68952385
4000 ---- 166.6666667 ---- 427.4376417 ---- 29.5354921
4250 ---- 177.0833333 ---- 454.1524943 ---- 31.38146036
4500 ---- 187.5000000 ---- 480.8673469 ---- 33.22742862
4750 ---- 197.9166667 ---- 507.5821995 ---- 35.07339687
5000 ---- 208.3333333 ---- 534.2970522 ---- 36.91936513
5250 ---- 218.7500000 ---- 561.0119048 ---- 38.76533339
5500 ---- 229.1666667 ---- 587.7267574 ---- 40.61130164
5750 ---- 239.5833333 ---- 614.4416100 ---- 42.4572699
6000 ---- 250.0000000 ---- 641.1564626 ---- 44.30323816
6250 ---- 260.4166667 ---- 667.8713152 ---- 46.14920641
6500 ---- 270.8333333 ---- 694.5861678 ---- 47.99517467
6750 ---- 281.2500000 ---- 721.3010204 ---- 49.84114292
7000 ---- 291.6666667 ---- 748.0158730 ---- 51.68711118
7250 ---- 302.0833333 ---- 774.7307256 ---- 53.53307944
7500 ---- 312.5000000 ---- 801.4455782 ---- 55.37904769


25psi (2.7006802721)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- STOCK BORE ENGINE
---------- 180Cid -------- 2.700680272 ----- 14.472



2500 ---- 104.1666667 ---- 281.3208617 ---- 19.43897607
2750 ---- 114.5833333 ---- 309.4529478 ---- 21.38287368
3000 ---- 125.0000000 ---- 337.5850340 ---- 23.32677128
3250 ---- 135.4166667 ---- 365.7171202 ---- 25.27066889
3500 ---- 145.8333333 ---- 393.8492063 ---- 27.2145665
3750 ---- 156.2500000 ---- 421.9812925 ---- 29.1584641
4000 ---- 166.6666667 ---- 450.1133787 ---- 31.10236171
4250 ---- 177.0833333 ---- 478.2454649 ---- 33.04625932
4500 ---- 187.5000000 ---- 506.3775510 ---- 34.99015693
4750 ---- 197.9166667 ---- 534.5096372 ---- 36.93405453
5000 ---- 208.3333333 ---- 562.6417234 ---- 38.87795214
5250 ---- 218.7500000 ---- 590.7738095 ---- 40.82184975
5500 ---- 229.1666667 ---- 618.9058957 ---- 42.76574735
5750 ---- 239.5833333 ---- 647.0379819 ---- 44.70964496
6000 ---- 250.0000000 ---- 675.1700680 ---- 46.65354257
6250 ---- 260.4166667 ---- 703.3021542 ---- 48.59744017
6500 ---- 270.8333333 ---- 731.4342404 ---- 50.54133778
6750 ---- 281.2500000 ---- 759.5663265 ---- 52.48523539
7000 ---- 291.6666667 ---- 787.6984127 ---- 54.42913299
7250 ---- 302.0833333 ---- 815.8304989 ---- 56.3730306
7500 ---- 312.5000000 ---- 843.9625850 ---- 58.31692821



NOW, using this link: http://not2fast.com/gasflow/velocity.shtml you will be able to figure up what size piping you will need for you power needs. Using an air tempurature of 75 degrees and a piping diameter of 2.5" and running 20 psi at 5000 RPM's, you will see a velocity of 240.4 ft/sec and a psig of 0.48. You typically want right at 300 ft/sec velocity in the main portion of your car's specific powerband. Anything over and psig begins increasing dramastically. Now, same psi at 6500 RPM's with the 2.5" piping, you will see a velocity of 312.5 ft/sec and a psig of 0.81. Let's bump it up to 7000 RPM's, same piping, velocity is 336.5 ft/sec and psig is 0.94. Notice how much your psig has risen with only being 36.5 ft/sec over critical velocity?

To plug in this info on a compressor map for a turbo use the boost
(20psiX14.7) ------or 2.3605 on the Y axis and your CFMs on the X axis.
------------
14.7




Next up is the .020" overbore 7M, you will notice a slight increase in CFM's over the stock bore. This is why some people think, "bigger is better".


10psi (1.68027210884)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- .020" OVERBORE ENGINE
---------- 180Cid -------- 1.680272109 ----- 14.472



2500 ---- 105.9027778 ---- 177.9454837 ---- 12.29584603
2750 ---- 116.4930556 ---- 195.7400321 ---- 13.52543063
3000 ---- 127.0833333 ---- 213.5345805 ---- 14.75501524
3250 ---- 137.6736111 ---- 231.3291289 ---- 15.98459984
3500 ---- 148.2638889 ---- 249.1236772 ---- 17.21418444
3750 ---- 158.8541667 ---- 266.9182256 ---- 18.44376905
4000 ---- 169.4444444 ---- 284.7127740 ---- 19.67335365
4250 ---- 180.0347222 ---- 302.5073224 ---- 20.90293825
4500 ---- 190.6250000 ---- 320.3018707 ---- 22.13252285
4750 ---- 201.2152778 ---- 338.0964191 ---- 23.36210746
5000 ---- 211.8055556 ---- 355.8909675 ---- 24.59169206
5250 ---- 222.3958333 ---- 373.6855159 ---- 25.82127666
5500 ---- 232.9861111 ---- 391.4800642 ---- 27.05086127
5750 ---- 243.5763889 ---- 409.2746126 ---- 28.28044587
6000 ---- 254.1666667 ---- 427.0691610 ---- 29.51003047
6250 ---- 264.7569444 ---- 444.8637094 ---- 30.73961508
6500 ---- 275.3472222 ---- 462.6582577 ---- 31.96919968
6750 ---- 285.9375000 ---- 480.4528061 ---- 33.19878428
7000 ---- 296.5277778 ---- 498.2473545 ---- 34.42836888
7250 ---- 307.1180556 ---- 516.0419029 ---- 35.65795349
7500 ---- 317.7083333 ---- 533.8364512 ---- 36.88753809


13psi (1.88435374149)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- .020" OVERBORE ENGINE
---------- 180Cid -------- 1.884353741 ----- 14.472



2500 ---- 105.9027778 ---- 199.5582955 ---- 13.78926862
2750 ---- 116.4930556 ---- 219.5141251 ---- 15.16819549
3000 ---- 127.0833333 ---- 239.4699546 ---- 16.54712235
3250 ---- 137.6736111 ---- 259.4257842 ---- 17.92604921
3500 ---- 148.2638889 ---- 279.3816138 ---- 19.30497607
3750 ---- 158.8541667 ---- 299.3374433 ---- 20.68390294
4000 ---- 169.4444444 ---- 319.2932729 ---- 22.0628298
4250 ---- 180.0347222 ---- 339.2491024 ---- 23.44175666
4500 ---- 190.6250000 ---- 359.2049320 ---- 24.82068352
4750 ---- 201.2152778 ---- 379.1607615 ---- 26.19961039
5000 ---- 211.8055556 ---- 399.1165911 ---- 27.57853725
5250 ---- 222.3958333 ---- 419.0724206 ---- 28.95746411
5500 ---- 232.9861111 ---- 439.0282502 ---- 30.33639097
5750 ---- 243.5763889 ---- 458.9840797 ---- 31.71531784
6000 ---- 254.1666667 ---- 478.9399093 ---- 33.0942447
6250 ---- 264.7569444 ---- 498.8957388 ---- 34.47317156
6500 ---- 275.3472222 ---- 518.8515684 ---- 35.85209842
6750 ---- 285.9375000 ---- 538.8073980 ---- 37.23102529
7000 ---- 296.5277778 ---- 558.7632275 ---- 38.60995215
7250 ---- 307.1180556 ---- 578.7190571 ---- 39.98887901
7500 ---- 317.7083333 ---- 598.6748866 ---- 41.36780587


15psi (2.02040816326)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- .020" OVERBORE ENGINE
---------- 180Cid -------- 2.020408163 ----- 14.472



2500 ---- 105.9027778 ---- 213.9668367 ---- 14.78488369
2750 ---- 116.4930556 ---- 235.3635204 ---- 16.26337206
3000 ---- 127.0833333 ---- 256.7602041 ---- 17.74186043
3250 ---- 137.6736111 ---- 278.1568878 ---- 19.22034879
3500 ---- 148.2638889 ---- 299.5535714 ---- 20.69883716
3750 ---- 158.8541667 ---- 320.9502551 ---- 22.17732553
4000 ---- 169.4444444 ---- 342.3469388 ---- 23.6558139
4250 ---- 180.0347222 ---- 363.7436224 ---- 25.13430227
4500 ---- 190.6250000 ---- 385.1403061 ---- 26.61279064
4750 ---- 201.2152778 ---- 406.5369898 ---- 28.09127901
5000 ---- 211.8055556 ---- 427.9336735 ---- 29.56976738
5250 ---- 222.3958333 ---- 449.3303571 ---- 31.04825575
5500 ---- 232.9861111 ---- 470.7270408 ---- 32.52674411
5750 ---- 243.5763889 ---- 492.1237245 ---- 34.00523248
6000 ---- 254.1666667 ---- 513.5204082 ---- 35.48372085
6250 ---- 264.7569444 ---- 534.9170918 ---- 36.96220922
6500 ---- 275.3472222 ---- 556.3137755 ---- 38.44069759
6750 ---- 285.9375000 ---- 577.7104592 ---- 39.91918596
7000 ---- 296.5277778 ---- 599.1071429 ---- 41.39767433
7250 ---- 307.1180556 ---- 620.5038265 ---- 42.8761627
7500 ---- 317.7083333 ---- 641.9005102 ---- 44.35465106


18psi (2.22448979591)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- .020" OVERBORE ENGINE
---------- 180Cid -------- 2.224489796 ----- 14.472



2500 ---- 105.9027778 ---- 235.5796485 ---- 16.27830628
2750 ---- 116.4930556 ---- 259.1376134 ---- 17.90613691
3000 ---- 127.0833333 ---- 282.6955782 ---- 19.53396754
3250 ---- 137.6736111 ---- 306.2535431 ---- 21.16179817
3500 ---- 148.2638889 ---- 329.8115079 ---- 22.7896288
3750 ---- 158.8541667 ---- 353.3694728 ---- 24.41745942
4000 ---- 169.4444444 ---- 376.9274376 ---- 26.04529005
4250 ---- 180.0347222 ---- 400.4854025 ---- 27.67312068
4500 ---- 190.6250000 ---- 424.0433673 ---- 29.30095131
4750 ---- 201.2152778 ---- 447.6013322 ---- 30.92878194
5000 ---- 211.8055556 ---- 471.1592971 ---- 32.55661257
5250 ---- 222.3958333 ---- 494.7172619 ---- 34.18444319
5500 ---- 232.9861111 ---- 518.2752268 ---- 35.81227382
5750 ---- 243.5763889 ---- 541.8331916 ---- 37.44010445
6000 ---- 254.1666667 ---- 565.3911565 ---- 39.06793508
6250 ---- 264.7569444 ---- 588.9491213 ---- 40.69576571
6500 ---- 275.3472222 ---- 612.5070862 ---- 42.32359634
6750 ---- 285.9375000 ---- 636.0650510 ---- 43.95142696
7000 ---- 296.5277778 ---- 659.6230159 ---- 45.57925759
7250 ---- 307.1180556 ---- 683.1809807 ---- 47.20708822
7500 ---- 317.7083333 ---- 706.7389456 ---- 48.83491885


20psi (2.36054421768)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- .020" OVERBORE ENGINE
---------- 180Cid -------- 2.360544218 ----- 14.472



2500 ---- 105.9027778 ---- 249.9881897 ---- 17.27392135
2750 ---- 116.4930556 ---- 274.9870087 ---- 19.00131348
3000 ---- 127.0833333 ---- 299.9858277 ---- 20.72870562
3250 ---- 137.6736111 ---- 324.9846466 ---- 22.45609775
3500 ---- 148.2638889 ---- 349.9834656 ---- 24.18348988
3750 ---- 158.8541667 ---- 374.9822846 ---- 25.91088202
4000 ---- 169.4444444 ---- 399.9811036 ---- 27.63827415
4250 ---- 180.0347222 ---- 424.9799225 ---- 29.36566629
4500 ---- 190.6250000 ---- 449.9787415 ---- 31.09305842
4750 ---- 201.2152778 ---- 474.9775605 ---- 32.82045056
5000 ---- 211.8055556 ---- 499.9763794 ---- 34.54784269
5250 ---- 222.3958333 ---- 524.9751984 ---- 36.27523483
5500 ---- 232.9861111 ---- 549.9740174 ---- 38.00262696
5750 ---- 243.5763889 ---- 574.9728364 ---- 39.7300191
6000 ---- 254.1666667 ---- 599.9716553 ---- 41.45741123
6250 ---- 264.7569444 ---- 624.9704743 ---- 43.18480337
6500 ---- 275.3472222 ---- 649.9692933 ---- 44.9121955
6750 ---- 285.9375000 ---- 674.9681122 ---- 46.63958763
7000 ---- 296.5277778 ---- 699.9669312 ---- 48.36697977
7250 ---- 307.1180556 ---- 724.9657502 ---- 50.0943719
7500 ---- 317.7083333 ---- 749.9645692 ---- 51.82176404


23psi (2.5646585034)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- .020" OVERBORE ENGINE
---------- 180Cid -------- 2.56462585 ----- 14.472



2500 ---- 105.9027778 ---- 271.6010015 ---- 18.76734394
2750 ---- 116.4930556 ---- 298.7611017 ---- 20.64407833
3000 ---- 127.0833333 ---- 325.9212018 ---- 22.52081273
3250 ---- 137.6736111 ---- 353.0813020 ---- 24.39754712
3500 ---- 148.2638889 ---- 380.2414021 ---- 26.27428152
3750 ---- 158.8541667 ---- 407.4015023 ---- 28.15101591
4000 ---- 169.4444444 ---- 434.5616024 ---- 30.02775031
4250 ---- 180.0347222 ---- 461.7217026 ---- 31.9044847
4500 ---- 190.6250000 ---- 488.8818027 ---- 33.78121909
4750 ---- 201.2152778 ---- 516.0419029 ---- 35.65795349
5000 ---- 211.8055556 ---- 543.2020030 ---- 37.53468788
5250 ---- 222.3958333 ---- 570.3621032 ---- 39.41142228
5500 ---- 232.9861111 ---- 597.5222033 ---- 41.28815667
5750 ---- 243.5763889 ---- 624.6823035 ---- 43.16489106
6000 ---- 254.1666667 ---- 651.8424036 ---- 45.04162546
6250 ---- 264.7569444 ---- 679.0025038 ---- 46.91835985
6500 ---- 275.3472222 ---- 706.1626039 ---- 48.79509425
6750 ---- 285.9370000 ---- 733.3227041 ---- 50.67182864
7000 ---- 296.5277778 ---- 760.4828042 ---- 52.54856303
7250 ---- 307.1180556 ---- 787.6429044 ---- 54.42529743
7500 ---- 317.7083333 ---- 814.8030045 ---- 56.30203182


25psi (2.7006802721)


RPM ------ NA ------------ TURBO CFM ----- lb/min
---------------- .020" OVERBORE ENGINE
---------- 180Cid -------- 2.700680272 ----- 14.472



2500 ---- 105.9027778 ---- 286.0095427 ---- 19.762959
2750 ---- 116.4930556 ---- 314.6104970 ---- 21.7392549
3000 ---- 127.0833333 ---- 343.2114512 ---- 23.7155508
3250 ---- 137.6736111 ---- 371.8124055 ---- 25.69184671
3500 ---- 148.2638889 ---- 400.4133598 ---- 27.66814261
3750 ---- 158.8541667 ---- 429.0143141 ---- 29.64443851
4000 ---- 169.4444444 ---- 457.6152683 ---- 31.62073441
4250 ---- 180.0347222 ---- 486.2162226 ---- 33.59703031
4500 ---- 190.6250000 ---- 514.8171769 ---- 35.57332621
4750 ---- 201.2152778 ---- 543.4181311 ---- 37.54962211
5000 ---- 211.8055556 ---- 572.0190854 ---- 39.52591801
5250 ---- 222.3958333 ---- 600.6200397 ---- 41.50221391
5500 ---- 232.9861111 ---- 629.2209940 ---- 43.47850981
5750 ---- 243.5763889 ---- 657.8219482 ---- 45.45480571
6000 ---- 254.1666667 ---- 686.4229025 ---- 47.43110161
6250 ---- 264.7569444 ---- 715.0238568 ---- 49.40739751
6500 ---- 275.3472222 ---- 743.6248110 ---- 51.38369341
6750 ---- 285.9375000 ---- 772.2257653 ---- 53.35998931
7000 ---- 296.5277778 ---- 800.8267196 ---- 55.33628521
7250 ---- 307.1180556 ---- 829.4276738 ---- 57.31258111
7500 ---- 317.7083333 ---- 858.0286281 ---- 59.28887701


Ok, lets use 5000 RPM's again with 2.5" and see what we get as a comparison, 244.4 ft/sec with a psig of 0.49. At 6000 RPM's you get 317.7 ft/sec and a pressure drop of 0.83 psig. At 7000 RPM's you get 342.1 ft/sec and a pressure drop of 0.97 psig, again, a drastic increase once critical velocity has been breached. Not a larg gain over a stock bore eh?




And finally, the .040" overbore 7M. You will notice that performance gains are not significant by increasing the size of the engine through an overbore, these numbers prove that ;). An overbore is typically used ONLY when there is not enough material on the piston walls to do a re-ring job of the original bore or due to damage of the cylinder bore through detonation or other means such as a foreign object entering the combustion chamber.


10psi (1.68027210884)


RPM -------- NA ------ TURBO CFM ---- lb/min
---------------- OVERBORED ENGINE (0.040")
---------- 185 Cid ----- 1.680272109 ---- 14.472

2500 ---- 107.0602 ---- 179.8902680 ---- 12.43022858
2750 ---- 117.7662 ---- 197.8792612 ---- 13.67324912
3000 ---- 128.4722 ---- 215.8682544 ---- 14.91626965
3250 ---- 139.1782 ---- 233.8572476 ---- 16.15929019
3500 ---- 149.8843 ---- 251.8464088 ---- 17.40232234
3750 ---- 160.5903 ---- 269.8354020 ---- 18.64534287
4000 ---- 171.2963 ---- 287.8243952 ---- 19.88836341
4250 ---- 182.0023 ---- 305.8133884 ---- 21.13138394
4500 ---- 192.7083 ---- 323.8023816 ---- 22.37440448
4750 ---- 203.4144 ---- 341.7915429 ---- 23.61743663
5000 ---- 214.1204 ---- 359.7805361 ---- 24.86045716
5250 ---- 224.8264 ---- 377.7695293 ---- 26.1034777
5500 ---- 235.5324 ---- 395.7585224 ---- 27.34649823
5750 ---- 246.2384 ---- 413.7475156 ---- 28.58951877
6000 ---- 256.9444 ---- 431.7365088 ---- 29.83253931
6250 ---- 267.6505 ---- 449.7256701 ---- 31.07557145
6500 ---- 278.3565 ---- 467.7146633 ---- 32.31859199
6750 ---- 289.0625 ---- 485.7036565 ---- 33.56161252
7000 ---- 299.7685 ---- 503.6926497 ---- 34.80463306
7250 ---- 310.4745 ---- 521.6816429 ---- 36.0476536
7500 ---- 321.1806 ---- 539.6708041 ---- 37.29068574


13psi (1.88435374149)

RPM -------- NA ------ TURBO CFM ---- lb/min
---------------- OVERBORED ENGINE (0.040")
---------- 185 Cid ----- 1.884353741 ---- 14.472

2500 ---- 107.0602 ---- 201.7392884 ---- 13.93997294
2750 ---- 117.7662 ---- 221.9131796 ---- 15.33396763
3000 ---- 128.4722 ---- 242.0870707 ---- 16.72796232
3250 ---- 139.1782 ---- 262.2609619 ---- 18.12195701
3500 ---- 149.8843 ---- 282.4350415 ---- 19.51596472
3750 ---- 160.5903 ---- 302.6089327 ---- 20.90995941
4000 ---- 171.2963 ---- 322.7828238 ---- 22.30395411
4250 ---- 182.0023 ---- 342.9567150 ---- 23.6979488
4500 ---- 192.7083 ---- 363.1306061 ---- 25.09194349
4750 ---- 203.4144 ---- 383.3046857 ---- 26.4859512
5000 ---- 214.1204 ---- 403.4785769 ---- 27.87994589
5250 ---- 224.8264 ---- 423.6524680 ---- 29.27394058
5500 ---- 235.5324 ---- 443.8263592 ---- 30.66793527
5750 ---- 246.2384 ---- 464.0002503 ---- 32.06192996
6000 ---- 256.9444 ---- 484.1741415 ---- 33.45592465
6250 ---- 267.6505 ---- 504.3482211 ---- 34.84993236
6500 ---- 278.3565 ---- 524.5221122 ---- 36.24392705
6750 ---- 289.0625 ---- 544.6960034 ---- 37.63792174
7000 ---- 299.7685 ---- 564.8698946 ---- 39.03191643
7250 ---- 310.4745 ---- 585.0437857 ---- 40.42591112
7500 ---- 321.1806 ---- 605.2178653 ---- 41.81991883


15psi (2.02040816326)

RPM -------- NA ------ TURBO CFM ---- lb/min
---------------- OVERBORED ENGINE (0.040")
---------- 185 Cid ----- 2.020408163 ---- 14.472

2500 ---- 107.0602 ---- 216.3053020 ---- 14.94646918
2750 ---- 117.7662 ---- 237.9357918 ---- 16.44111331
3000 ---- 128.4722 ---- 259.5662816 ---- 17.93575744
3250 ---- 139.1782 ---- 281.1967714 ---- 19.43040156
3500 ---- 149.8843 ---- 302.8274633 ---- 20.92505965
3750 ---- 160.5903 ---- 324.4579531 ---- 22.41970378
4000 ---- 171.2963 ---- 346.0884429 ---- 23.9143479
4250 ---- 182.0023 ---- 367.7189327 ---- 25.40899203
4500 ---- 192.7083 ---- 389.3494224 ---- 26.90363616
4750 ---- 203.4144 ---- 410.9801143 ---- 28.39829424
5000 ---- 214.1204 ---- 432.6106041 ---- 29.89293837
5250 ---- 224.8264 ---- 454.2410939 ---- 31.3875825
5500 ---- 235.5324 ---- 475.8715837 ---- 32.88222662
5750 ---- 246.2384 ---- 497.5020735 ---- 34.37687075
6000 ---- 256.9444 ---- 519.1325633 ---- 35.87151487
6250 ---- 267.6505 ---- 540.7632551 ---- 37.36617296
6500 ---- 278.3565 ---- 562.3937449 ---- 38.86081709
6750 ---- 289.0625 ---- 584.0242347 ---- 40.35546121
7000 ---- 299.7685 ---- 605.6547245 ---- 41.85010534
7250 ---- 310.4745 ---- 627.2852143 ---- 43.34474947
7500 ---- 321.1806 ---- 648.9159061 ---- 44.83940755


18psi (2.22448979591)

RPM -------- NA ------ TURBO CFM ---- lb/min
---------------- OVERBORED ENGINE (0.040")
---------- 185 Cid ----- 2.224489796 ---- 14.472

2500 ---- 107.0602 ---- 238.1543224 ---- 16.45621355
2750 ---- 117.7662 ---- 261.9697102 ---- 18.10183183
3000 ---- 128.4722 ---- 285.7850980 ---- 19.74745011
3250 ---- 139.1782 ---- 309.6004857 ---- 21.39306839
3500 ---- 149.8843 ---- 333.4160959 ---- 23.03870204
3750 ---- 160.5903 ---- 357.2314837 ---- 24.68432032
4000 ---- 171.2963 ---- 381.0468714 ---- 26.3299386
4250 ---- 182.0023 ---- 404.8622592 ---- 27.97555688
4500 ---- 192.7083 ---- 428.6776469 ---- 29.62117516
4750 ---- 203.4144 ---- 452.4932571 ---- 31.26680881
5000 ---- 214.1204 ---- 476.3086449 ---- 32.91242709
5250 ---- 224.8264 ---- 500.1240327 ---- 34.55804537
5500 ---- 235.5324 ---- 523.9394204 ---- 36.20366365
5750 ---- 246.2384 ---- 547.7548082 ---- 37.84928193
6000 ---- 256.9444 ---- 571.5701959 ---- 39.49490022
6250 ---- 267.6505 ---- 595.3858061 ---- 41.14053387
6500 ---- 278.3565 ---- 619.2011939 ---- 42.78615215
6750 ---- 289.0625 ---- 643.0165816 ---- 44.43177043
7000 ---- 299.7685 ---- 666.8319694 ---- 46.07738871
7250 ---- 310.4745 ---- 690.6473571 ---- 47.72300699
7500 ---- 321.1806 ---- 714.4629673 ---- 49.36864064


20psi (2.36054421768)

RPM -------- NA ------ TURBO CFM ---- lb/min
---------------- OVERBORED ENGINE (0.040")
---------- 185 Cid ----- 2.360544218 ---- 14.472

2500 ---- 107.0602 ---- 252.7203361 ---- 17.46270979
2750 ---- 117.7662 ---- 277.9923224 ---- 19.2089775
3000 ---- 128.4722 ---- 303.2643088 ---- 20.95524522
3250 ---- 139.1782 ---- 328.5362952 ---- 22.70151294
3500 ---- 149.8843 ---- 353.8085177 ---- 24.44779697
3750 ---- 160.5903 ---- 379.0805041 ---- 26.19406468
4000 ---- 171.2963 ---- 404.3524905 ---- 27.9403324
4250 ---- 182.0023 ---- 429.6244769 ---- 29.68660012
4500 ---- 192.7083 ---- 454.8964633 ---- 31.43286783
4750 ---- 203.4144 ---- 480.1686857 ---- 33.17915186
5000 ---- 214.1204 ---- 505.4406721 ---- 34.92541958
5250 ---- 224.8264 ---- 530.7126585 ---- 36.67168729
5500 ---- 235.5324 ---- 555.9846449 ---- 38.41795501
5750 ---- 246.2384 ---- 581.2566313 ---- 40.16422273
6000 ---- 256.9444 ---- 606.5286177 ---- 41.91049044
6250 ---- 267.6505 ---- 631.8008401 ---- 43.65677447
6500 ---- 278.3565 ---- 657.0728265 ---- 45.40304219
6750 ---- 289.0625 ---- 682.3448129 ---- 47.1493099
7000 ---- 299.7685 ---- 707.6167993 ---- 48.89557762
7250 ---- 310.4745 ---- 732.8887857 ---- 50.64184534
7500 ---- 321.1806 ---- 758.1610082 ---- 52.38812936


23psi (2.56462585034)

RPM -------- NA ------ TURBO CFM ---- lb/min
---------------- OVERBORED ENGINE (0.040")
---------- 185 Cid ----- 2.56462585 ---- 14.472

2500 ---- 107.0602 ---- 274.5693565 ---- 18.97245415
2750 ---- 117.7662 ---- 302.0262408 ---- 20.86969602
3000 ---- 128.4722 ---- 329.4831252 ---- 22.76693789
3250 ---- 139.1782 ---- 356.9400095 ---- 24.66417976
3500 ---- 149.8843 ---- 384.3971503 ---- 26.56143935
3750 ---- 160.5903 ---- 411.8540347 ---- 28.45868123
4000 ---- 171.2963 ---- 439.3109190 ---- 30.3559231
4250 ---- 182.0023 ---- 466.7678034 ---- 32.25316497
4500 ---- 192.7083 ---- 494.2246878 ---- 34.15040684
4750 ---- 203.4144 ---- 521.6818286 ---- 36.04766643
5000 ---- 214.1204 ---- 549.1387129 ---- 37.9449083
5250 ---- 224.8264 ---- 576.5955973 ---- 39.84215017
5500 ---- 235.5324 ---- 604.0524816 ---- 41.73939204
5750 ---- 246.2384 ---- 631.5093660 ---- 43.63663391
6000 ---- 256.9444 ---- 658.9662503 ---- 45.53387578
6250 ---- 267.6505 ---- 686.4233912 ---- 47.43113538
6500 ---- 278.3565 ---- 713.8802755 ---- 49.32837725
6750 ---- 289.0625 ---- 741.3371599 ---- 51.22561912
7000 ---- 299.7685 ---- 768.7940442 ---- 53.12286099
7250 ---- 310.4745 ---- 796.2509286 ---- 55.02010286
7500 ---- 321.1806 ---- 823.7080694 ---- 56.91736245


25psi (2.7006802721)

RPM -------- NA ------ TURBO CFM ---- lb/min
---------------- OVERBORED ENGINE (0.040")
---------- 185 Cid ----- 2.700680272 ---- 14.472

2500 ---- 107.0602 ---- 289.1353701 ---- 19.97895039
2750 ---- 117.7662 ---- 318.0488531 ---- 21.9768417
3000 ---- 128.4722 ---- 346.9623361 ---- 23.97473301
3250 ---- 139.1782 ---- 375.8758190 ---- 25.97262431
3500 ---- 149.8843 ---- 404.7895721 ---- 27.97053428
3750 ---- 160.5903 ---- 433.7030551 ---- 29.96842559
4000 ---- 171.2963 ---- 462.6165381 ---- 31.96631689
4250 ---- 182.0023 ---- 491.5300211 ---- 33.9642082
4500 ---- 192.7083 ---- 520.4435041 ---- 35.96209951
4750 ---- 203.4144 ---- 549.3572571 ---- 37.96000948
5000 ---- 214.1204 ---- 578.2707401 ---- 39.95790078
5250 ---- 224.8264 ---- 607.1842231 ---- 41.95579209
5500 ---- 235.5324 ---- 636.0977061 ---- 43.9536834
5750 ---- 246.2384 ---- 665.0111891 ---- 45.9515747
6000 ---- 256.9444 ---- 693.9246721 ---- 47.94946601
6250 ---- 267.6505 ---- 722.8384252 ---- 49.94737598
6500 ---- 278.3565 ---- 751.7519082 ---- 51.94526729
6750 ---- 289.0625 ---- 780.6653912 ---- 53.94315859
7000 ---- 299.7685 ---- 809.5788741 ---- 55.9410499
7250 ---- 310.4745 ---- 838.4923571 ---- 57.93894121
7500 ---- 321.1806 ---- 867.4061102 ---- 59.93685117


It's your turn to plug in those numbers that I've done in the above post to see what kind of flow you will get ;).
 
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