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Quote:

Originally Posted by Raylar (Post 2051714)

Bob:
Nice start to a great series of eye opening tests! Glad to see my statement about octane not making more power is here in black and white to close that old wives tale! Keep it com'in!

Regards,
Ray @ Raylar

I agree Indeed.. :) Jamie

Quote:

Originally Posted by bobl (Post 2051506)

Ok guys, we're on our way. Just completed all the base line testing on the test boat. We made 5 different runs with GPS. Different directions and even different drivers. We went from a slowest of 62.6 to a fastest of 63.5. All but one run was under 63. I just finished prop shaft dyno testing the engine. Again I made 3 pulls and they were within 1 HP of each other. So, what did it make at the prop you ask???? 387 HP at 5000 RPM!!! That is a solid 10% loss through the drive.

Another bit of trivia. THe boat has 2 gas tanks. One has 87 octane and the other has 93 octane. I switched to the 87 for one pull and it didn't change the HP one bit.

So, we have our baseline data. We'll get the exhaust switched in the next couple of days and dyno it again.

This is good stuff! :D

What temperature and pressure are you correcting the horsepower to?

I can't wait to hear about the next set of tests. Don't forget to put it all back to stock at the end to be sure nothing changed with the powertrain during the tests.

Michael

I have an electronic weather station. We are at 800' elevation. Ambient air temp was upper 70's. However I placed the weather station right by the flame arrestor to get a more accurate inlet air temp. That temp was 88 degrees. I'm using the "standard" correction method. The final correction factor was 5%, uncorrected HP was 360.

Excellent test data and test method to insure effects of engine compartment air temperature at flame arrestor versus the general ambient air temperature that these weather stations usually are reading is accounted for. That 10% drive loss hp answers a lot of questions for me.

Anything new? Is the testing still going to happen?

Quote:

Originally Posted by Bill 3 (Post 2065509)

Anything new? Is the testing still going to happen?

It's currently in process. You should have some finite answers soon :cool:

anymore new test information ?

Should have some definite numbers this week. Still waiting on a set of risers from Dana.

It's been about 3 weeks. Any results yet?