Pitch Settings

[ToddP]

With my rotax 532, 2.58 Gearbox and 60&quot; 3 blade warp drive set at 10 degrees I am only getting 6200 max RPM. &nbsp;What blade pitch are people using on similar setups with the 532 or 582 engines?<br><br>Thanks,<br><br>Todd<br>

[Rotorhead]

Todd<br><br>My 532 - 2.58 60 &quot; 3 blade warp drive is set at 10 degs<br>bought a new powerfin 62-3 blade thought try it before gets to cold<br>

[MattPearson]

Todd,<br> What is your EGT temp at 6200?<br>Could it be that you need leaner main jets?

[ToddP]

I believe the Main Jets are about right. &nbsp;The stock jets are 165 and I've adjusted down to 160 for elevation. &nbsp;I'll get a better idea today.<br><br>I don't remember where, but I remember seeing someone wrote the Rotax 532 worked best with the warp drive 3-blade at 7-8 degrees. &nbsp;It seemed very low at the time...but I may get there before I see 6500.<br><br>Todd

Todd,<br><br>Before you start messing with your jets I suggest the following:<br><br>Refer the manufacturers instructions at all times - you may void your warranty otherwise!!<br><br>Chain your machine down in a spotlessly clean area with no rocks, etc to be sucked into the prop, start the engine, warm it up and check speed at full power with no choke, progressively increase the choke ***very slowly*** and see if there is an increase in the revs, if there is then you should make the jets just slightly bigger and try again as the increase in revs is caused by an enriched mixture.<br><br>If there is no increase in revs (the engine begins to hesitate without revving up) then drop your jet sizes to the next size down and see what happens, if there is an increase in revs with the addition of choke then the mixture is lean and needs very slight enrichment, go up a half step between the prior big jets and the ones that you have in the carbs now, try the process again.<br><br>Be mindful of the fact that an engine that runs lean may suffer from detonation at high speeds and this will affect the longevity of the engine, when you find the most ideal jets they should be made just a tad more rich to preserve your engine´s life, and yours... you want to operate at the rich end of the spectrum, not the lean end.<br><br>Then start to vary the pitch angle, you should find out what the drag polars are for the prop that you are using so you can pick the best angle of attack to set the blades at, failing obtaining them, as they are usually impossible to get, just fiddle and see what happens.<br><br>You should think about what you are going to do when flying, do you want to maximise thrust for take off or thrust for cruising??<br><br>You may set your blade angle to suit either case or make a compromise somewhere between..it sounds to me that you´re in for a good deal of fiddling, get some scales, graph paper and pencil, record thrust and revs for each pitch setting and then make your decisions on what you mainly use the machine for. Your graph should record the thrust (vertical axis) versus RPM (horizontal axis) from about 3000 RPM to max permissable revs, with particular attention to the portion between cruise power and take off power.<br><br>Have fun, at least you have a prop you can vary the pitch on, like I don´t..<br><br>Regards,<br><br>Nicholas Tomlin.<br><br>

Todd,<br><br>I should add to make sure there are no overhanging tree branches or anything within cooee of the prop, I suffered on such incident which cost me 1.5 inches of prop diameter, most embarrasing..<br><br>If you are restraining the gyro with rope make sure it has a breaking strain at least five times the thrust that your machine generates, so it wont run away with you in the seat... you must also make sure that the scales - usually spring tension scales are only between tow loops tied in the rope, in other words the rope is continuous between your anchor point and the gyro, there is only sufficient slack in it to accommodate the scales, and if the scales tear apart then the rope will catch you .... watch out for the sudden stop at the end.

[blackbird]

Todd, I am running a 532 with a 3-blade Warp drive prop. However, I am on a belt system drive. I am turning 6400 rpm at full throttle , egt is in cruise at 1100 degrees @ 5800 rpms. Pitch is set at 8.5 degrees at the tip.

[ToddP]

Blackbird,

Thanks for the reply. I've got it dialed down to about 9.5 degrees of pitch and top rpm is 6350. If I drop it down to 9 degrees it will hit 6600. This engine is very peaky. I've heard of people running these engines over 7000 rpm, but if I remember right the factory redline is 6500. Does anyone have an opinion, should I keep it at 9.5 degrees and 6350 (probably not getting the full hp) or take it down to 9 degrees and 6600 (slightly over redline).

[PW_Plack]

Todd,

Do you not see a slight rise in RPM at altitude? If I were in your area, and likely to need to gain altitude for corss-country flight, I'd take the 6350, and see if higher altitudes or warmer days allow the engine to get near redline, before I revved much higher on the ground.

And then, there's the whole issue of whether your tach is right on the money!