Quote:
Originally Posted by BlueOval Ralph
Evan this is incorrect as far as how Ford did it!!!
Old cars were rated differently (gross hp) from the factory with no engine accessories and free-flowing exhaust—new engines are rated with everything in place, including emission controls.
The way Ford did it was there were 3 Horsepower ratings.
A curve was no accessorys (fan, alt, water pump and open exhaust)
B curve was some accessorys (somewhere in between A curve and C curve)
C curve was with Fan, waterpump, alt and exhaust back pressure as installed in vehicle. This was the factory published rating.
all the above were corrected to SAE J 607 which was ans is 29.92 baro, 60 degrees carb air.
Mose Noland could give you more of the details if he remebers
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That is true of pre 1972 cars Ralph, but after that they were "net" with everything installed as today. I used mostly mid 70's cars for that reason.
Regardless of how, or who done what, potential is what a class racers is after.
If eng A is rated at 99% of it's potential, who going to try it? Nobody.
If eng B is rated at 50% of it's potential, everybody will consider it....unless it's hidden, then only Billy Nees or Bob Shaw will find/try it! LOL!
So the only real question is then, what is the true potential of the new motors?
Then, can they be factored the way the old motors were?
In other words;
A is 400hp@ 80% = 500hp 100%
B is 400hp@40% = 1000hp 100%
If both engines start out at .58 factor, one will obviously cause a ruckus.(as we have seen with turbo or supercharged engines)
So, do you rate older or N/A engines at .58 to start and pressurised eng 1.1 to start?
What is a fair place to start pressure engines? Maybe starting them at 1.3hp/cu.in IS fair?