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Interesting stuff really.....I am like a sponge when reading these tests....thanks for sharing, and I especially like the conclusion about VE vs Compression. I don't know where he has been...this has always been true to an extent, depending on starting points. For example, a 10% VE improvement on a 10 to 1 compression engine is equal to taking the compression up another full point to 11 to 1. However, another example of a 8 to 1 compression motor would need a VE improvement of 12% to equal one compression point up! So, it's proportionate to the compression ratio starting point.
The fan thing is interesting. I don't know what kind of fans those are with regard to pitch and CFMs but they are pretty crummy based on my own tests, research and a few other noteable testing entities.....and just work uptake alone. You cannot come to any conclusion without some sort of fan shroud either. You also have to encapsulate them in a shroud of some sort for maximum effectiveness and testing in my opinion. Flinging in freeair will have differing results (including complete cavitation taking up very little energy, if any due to eddy currents) because all the air is literally sliding off the ends of the blades. Most articles that I have read, and manufactures claims are consistent with about a 100% CFM improvement issue with a shround vs. without...depending on fan size and design. And, moreover, the outcome of the hp take up by these are not in the accuracy of the machine. Hmmm?....see next paragraph. But, since I know little of the fans with regards to pitch, blade width and length, it's not one that I would correlate to what is in your vehicle at all. What fans comes from "Clings"? Don't know them?
Just my two cents for what it's worth on dyno issues, whilst the Superflow 900 series dyno was the selection (I have used them many years ago), the error rates for these machines were higher than the last digit accuracy rate for the testing he was doing full scale (for example..the last digit is in tenths of hp, and the real error is probably in the 2 hp range), and I didn't see him mention any statistical error corrective correlations. And, the error is also larger at the lower end from a techical standpoint and a So, it's probably a 5% device at best, even tho calibrated regularily. I am assuming that he was monitoring and took into account all the intricacies such as barometric pressure, induction temperature, oil temperature, engine temperature, relative humidity, ambient temperature and so forth? They all play a part.
Just my usual science dribble.
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Steve Jack
Engineering & Marketing Technologies
ConceptOne Brackets and Pulleys
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