开云体育

?Thanks Michael,?Your stall is 25 knots?? That is pretty much book.? Mine is way higher.? I hope we can figure this out.? If it were my ASI, then the top speeds would be high too. right? Not really..... i have seen an ASI where someone blew into the end of it only read correct from about 35 to 50 knots over that it would go up to 90 knots and under 35 it would show about 15, so it can happen? If my revmeter (tach) was reading really low. then my engine wouldn't start getting hot at 5800 rpm.? But I should check them out. Your engine should run at max revs without overheating for a considerable period of time eg? our 503's air cooled will run for over 1 hour flat out 5600 rpm without any problems, just to try and keep up with the 618's / 582's.?I have a digital light tach that I tried.? It registered 1100 to 1700 RPM when I was showing 3000 on my engine tach.? I thought the digital tach was wrong. All i can suggest is eliminate the obvious first, replace / borrow a new tacho and check it out first because overreving the engine will cause it to destruct, once that's right check the ASI. Use a GPS and fly four legs, say a big square, go North for say 2 minutes and check your ASI against your ground speed then turn East and do the same, after completing the four legs average the ground speed and you have your average taking into consideration the wind direction by flying all four directions. Do this three times once at say 40 knots and them at 50 and again at 60 and it will tell you if its out an a particular range. Otherwise send it to an instrument tech and get him to check it.

Finally - where is your ASI pickup located this is also very important.

Thanks Michael