if youre still able to, install a pipe, for example MTW or KS on the 3W and use a Engel Super Silence 24x10 (very thin CFK Prop)
http://www.engelmt.de.
im flying a 3w75 in my extra, with the original Pefa can and i have tryed several Props:
Mejzlick 26x10n -not worth to say about,forget this prop on this engine , Mejzlick 24x10th and 24x10 Engel - the 24x10 th climbs good(out of torque roll) and has a very good performance on throttle- even climbs well in F3A programs, but 6450 are not enough at all. -with a pipe this prop would be the best combination for that plane ever.
the 24x10 engel gets really cool rpms :7150 -thats enough power to have really fun ! -the only disadvantage is that "tracking" on throttle isnt so extremly good like with the 24x10th - may com from the thin prop...
at least i love to fly this prop, no problems with the heavy weight of my 3W extra (standart
)...
Regards, Chris