Cheat sheet
Injector flow & hp support
Flow converts with one factor — cc/min ÷ 10.5 = lb/hr for petrol. The horsepower columns are that flow at an 80% duty ceiling, which is the headroom you want for cold starts, bad fuel and next year's power.
| cc/min | lb/hr | 4 cyl | 6 cyl | 8 cyl | 4 cyl on E85 |
|---|---|---|---|---|---|
| 190 | 18.1 | 105 | 160 | 210 | 90 |
| 240 | 22.9 | 135 | 200 | 265 | 115 |
| 310 | 29.5 | 170 | 260 | 345 | 145 |
| 380 | 36.2 | 210 | 315 | 420 | 180 |
| 440 | 41.9 | 245 | 365 | 490 | 205 |
| 550 | 52.4 | 305 | 455 | 610 | 260 |
| 650 | 61.9 | 360 | 540 | 720 | 305 |
| 750 | 71.4 | 415 | 625 | 830 | 350 |
| 850 | 81.0 | 470 | 705 | 940 | 400 |
| 1000 | 95.2 | 555 | 830 | 1110 | 470 |
| 1300 | 123.8 | 720 | 1080 | 1440 | 610 |
| 1650 | 157.1 | 915 | 1370 | 1830 | 775 |
| 2000 | 190.5 | 1110 | 1660 | 2215 | 940 |
Petrol columns use BSFC 0.55, the E85 column 0.65 — ethanol needs roughly a third more fuel for the same power. Ratings assume the usual 3 bar / 43.5 psi test pressure; raising base pressure raises flow with the square root of pressure.