Analysis Report Peak Tq = 381.0 @ 3500 RPM 1.067 Ft Lbs per CuIn Peak HP = 296.0 @ 4700 RPM 0.829 HP per CuIn Maximum Exhaust System Backpressure 'EX PRS' is 2 ''Hg. This is low for a street vehicle with a full exhaust system. This is simulating either an extremely free flowing exhaust system or open headers or open exhaust manifolds. This may be illegally loud for street operation. Typical ranges of Exhaust System Backpressure are listed on page 32 in the User's Manual. You can lower the Back pressure by increasing EXH SYSTEM CFM RATING in the EXHAUST SYSTEM menu. Lowering the EXH SYSTEM CFM RATING will simulate a quieter, more restrictive exhaust system. Most dyno tests are done with open headers, which are simulated with EXH SYSTEM CFM RATING = 100000. Maximum Fuel Flow 'FL FLW' is 159 lbs/hr GAS. This is equal to 27.2 gallons per hour of fuel flow. For an injected engine with one injector per cylinder, you will require at least 20 lbs/hr injectors. FL FLW will only change if air flow changes or if you inject nitrous. The ENGINE ANALYZER assumes 12.5:1 A/F for gasoline and 5:1 for alcohol (methanol) for all conditions. You can not richen or lean out the fuel mixture. Your DESIRED HP PEAK RPM does not match the RECOMMENDATIONS: RPM in the CALCULATE PERFORMANCE CONDITIONS menu. Change the RECOMMENDA- TIONS RPM and recalculate performance. Then check the APPROX CAM RECOMMENDATIONS at the bottom of the calculated performance report. It will give approximate cam specs to produce a HP peak at this RPM with your current cylinder heads. The Average Piston Speed 'PSN SP' is 2917 ft/min at your DESIRED HP PEAK RPM of 5000 RPM. This is somewhat high, requiring strong, light reciprocating parts. The Maximum Average Piston Speed 'PSN SP' is 2975 ft/min at the Performance Calculations Maximum RPM of 5100 RPM. This is somewhat high (if you want to run this entire speed range), requiring light, high strength reciprocating components. A mild street engine should limit PSN SP to a range of 2500-2750 ft/min with production quality rods. To run at 2750 ft/min or higher, you will need 'better than production' reciprocating components (connecting rods & bolts, pistons, etc.). PSN SP (average piston speed in ft/min) and PSN GS (peak piston Gs) are indicators of how severely you are stressing the engine's rotating components. To lower PSN SP and PSN GS, you must shorten the piston STROKE or design the engine for a lower RPM range. See pages 53, 54 and 160 in the manual. Maintaining low PSN SP and PSN GS are critical for 'keeping the engine together'. OVER-REVVING PARTS BEYOND THEIR INTENDED LIMIT IS UNSAFE FOR THE ENGINE, YOURSELF AND BYSTANDERS. The Intake Runner Velocity 'IN VEL' is 366 ft/sec at your DESIRED HP PEAK RPM of 5000 RPM. This is Very high and indicates you will need a larger INTAKE RUNNER DIAMETER for less restriction and stronger intake tuning. For these engine specs, an IN VEL of about 240 should work well. If the IN VEL is approximately 30-80 Ft/Sec higher than this, you will likely improve torque below this RPM, but lose some HP. The Inertia tuning of this intake is tuned to 3767 RPM, which is somewhat lower than your DESIRED HP PEAK RPM of 5000 RPM. This RPM is about where the torque peak should occur and should pro- duce good peak torque. If you specify shorter and/or larger diameter intake runners, you will likely gain Peak HP and lose some Peak Torque. Your DESIRED HP PEAK RPM does not match the RECOMMENDATIONS: RPM in the CALCULATE PERFORMANCE CONDITIONS menu. Change the RECOMMENDA- TIONS RPM and recalculate performance. Then check the INTAKE RUNNER RECOMMENDATIONS at the bottom of the calculated performance report. It will give INTAKE RUNNER LENGTH and RUNNER DIAMETER you can try to produce strong intake inertia tuning at your DESIRED HP PEAK RPM. The Exhaust Runner Velocity 'EX VEL' is 403 ft/sec at your DESIRED HP PEAK RPM of 5000 RPM. This is somewhat high and indicates you will need a larger EXHAUST RUNNER DIAMETER for less restriction and stronger exhaust tuning. Exhaust tuning is usually best with 300 ft/sec 'EX VEL'. At 5 different RPMs, Spark Advance 'SPKADV' is retarded to avoid detonation. Retarding SPKADV does reduce performance, but allows this engine to safely operate with this OCTANE fuel. You can reduce the likelihood of detonation, by increasing FUEL OCTANE or DEW POINT (humidity), or reducing INTAKE AIR TEMP or COOLANT TEMP in the CALCULATE PERFORMANCE CONDITIONS menu, or reducing COMPRESSION RATIO in the BASE ENGINE menu. Also, anything which reduces performance, or shifts the performance curve to a higher RPM range will also reduce the likelihood of detonation. By reducing the likelihood of detonation, you avoid the necessity of retarding SPKADV. Retarding SPKADV is not necessarily a 'bad thing'. The best per- formance for a particular RPM range and FUEL OCTANE may come with retarded spark. Just be sure to retard spark in the actual engine to avoid detonation which will cause engine damage. Also, retarding spark increases exhaust temperatures, which can damage exhaust valves, turbo turbines, etc. The % Exhaust to Intake Flow Capacity 'VALVE EXH/INT %' is 86.2 %. This is somewhat high, and indicates you could be opening the exhaust valve too early or you could improve performance by improving intake valve flow and intake cam profile. The most common 'rule of thumb' is to design for around 75% EXH/INT flow capability. To reduce VALVE EXH/INT %: - Increase the INTAKE VALVE DIAMETER and/or VALVE FLOW COEF - Increase the INTAKE OPEN @ .050 and CLOSE @ .050, MAX TAPPET LIFT and/or ROCKER ARM RATIO in the CAM/VALVE TRAIN menu - Reduce EXHAUST OPEN @ .050 in the CAM VALVE TRAIN MENU You can reduce VALVE EXH/INT % by changing other specs, but that may also reduce performance. End of Analysis Report