D dust w/ mvvs 40--- what prop??
 

Alright, I have a Diamond Dust with a MVVS .40 and a fai grrt pipe from Morris. The 8x8 prop I'm running doesn't sound like its coming up on the pipe like it should. What size prop would make this configuration work best? And is there a way to really tune the fai grrt pipe? I could slide it forward or back about an inch where it meets the header and still meet the silicon o-rings (or seal, whatever). Not sure what I'm doing here, looking for some advice.

Thanks,
Josh

RE: D dust w/ mvvs 40--- what prop??
 

Do you have the old, or the "newer" GRRT? The old one has four mounting bolt holes, the newer version has six mounting holes (two additional ones near the front bearing)...

You could try the following props (all APC):
7x7 sport... not really recommended, since not suited for extreme RPM... it may or may not let go, but the engine should be able to swing it...
7.2x8.0 and 7.2x8.6... but the engine will probably not get on the pipe with that last one... the 7.2x8.0 may work with a little trimming...
7.8x6.0 carbon... this may be a good candidate for first tests and bench running (slightly trimmed perhaps)... and it is probably the best flying prop out of this lot for a Dust...
7.8x7.0 carbon... this would be a good flying prop, with some trimming probably, on a sleek plane

Do not over rev these engines... 27000-28000 is about as far as you want to take them if you expect some life out of them...

RE: D dust w/ mvvs 40--- what prop??
 

Rudeboy, he doesn't say he has the GRRT motor, just the pipe... He might have the Q500 motor as a rear exhaust like I do on my DD. Fist thing to remember is the MVVS motors need to break in. Mine was a ***** to get on pipe until I had a dozen flights on it. I run an APC 8x8 on 15% cool power with no problems. Great motor, I did have a problem with the GRRT pipe breaking so I went to a higher quality macs pipe.