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What I have found over the years is that the 370cc injectors max out around 400 RWHP.
The early style 555cc injectors max out around 600 RWHP.
The real 740cc injectors max out around 800 RWHP.
The 850cc injectors max out about 840 RWHP.
I have seen a single stock fuel pump max out and start dropping pressure as early as
500 RWHP, I have seen a few provide as much as 650 RWHP before dropping fuel pressure. Most stock pumps tend to start dropping pressure around 550 to 600 RWHP.
The type of fuel used does have a play in this, as fuels do burn at different rates.
The numbers I am giving above are at close to zero correction factors on dynojets.The correction factors that have been established and used in dynojet software , are suppose to correct for conditions to allow a car being dyno tested to read reasonably the same in any condition the dyno is used in.
The formulas are based on the amount of oxygen that is in the air that the engine is breathing. The more oxygen, the more fuel can be burned, and thus more horsepower. Of course these formulas are not perfect. They were developed to provide a good approximation for the variables of humidity, temperature, and absolute pressure. I have noticed that turbo cars tested in higher altitudes tend to measure higher than turbo cars that have the same mods that are tested at or near sea level.
Those that have driven a non turbo car near sea level, and then driven the same car in the mountains know that the power is greatly reduced at higher elevations. If the engine is underpowered at sea level, the car can feel like the engine has literally lost half of it’s power at high elevations.
Turbo cars also loose power at higher elevations, but the turbo can make up for some of that loss. Since you can increase the moderate boost levels, to the same level as sea level boost levels, your only loosing the difference in Atmospheric pressure.
Since the dyno software does not account for the difference in turbo and non turbo cars, I believe that is the reason why the numbers seem to read higher than what seems to be normal on turbo cars measured in higher elevations when SAE or STD correction factors are used.
In my mind, it would seem that the formula should include if the car is force fed. In the end, A dyno is mainly a tuning tool to allow a tuner to make a car safe in the conditions the car is being used in and also to extract the reasonable horsepower. It also allows you to measure gains to make sure your going the right direction with the mods your installing or testing.
It is great for a group to all go to the same dyno, with the same type of car, with everyone having different mods, this absolutely allows you to establish what mods work and provide the greatest differences. The guys in Edmonton Canada live in a area where the altitude is higher. Because they have less air, the actual power they have in Edmonton is less than the corrected number the dyno was showing. The numbers that the dyno was giving is suppose to be the corrected number if the car was at sea level in ideal conditions.
The dynojet also offers a UNCORRECTED number and that is suppose to be the actual horsepower the car is putting out without any correction.
Tom’s 800+ RWHP number was the SAE corrected number for what the SAE standards believe the car would put out in ideal conditions.
Tom’s uncorrected number was about 750RWHP.
The uncorrected number is what the car was really producing in the conditions the car was tested. The uncorrected number was the real demand on the fuel system when testing.
Tom’s car did not have any issues getting to, or holding the air fuel target in the tested environment. If Tom does use the car at sea level, he will be on the raggedy edge of what the injectors he has can support with Q-16 fuel.
Tom's car makes about 750 RWHP in the Edmonton conditions. The SAE correction Factor says Tom's car would make 800+ in ideal sea level conditions.
The reality is, he probably would make somewhere in the middle at the same boost level, but he probably could produce more boost at sea level and more than likely would make the full 800+ RWHP at full boost.
If Tom does use the car at full tilt at Sea level, It would be wise to make sure the air fuel ratio does stay in a reasonable range and I would highly recommend larger injectors.
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