RCU Forums - View Single Post - EXTREME FLIGHT RC 88 inch YAK-54/Brillelli 366GT Build thread
Old 03-07-2007, 07:20 PM
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yarom
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Default RE: EXTREME FLIGHT RC 88 inch YAK-54/Brillelli 366GT Build thread


Based on what you describe below, could the B60 be in the power band of a da-50?

We break in the DAs on 22x8 pretty aggressive props and move to a strong 23x8 after a few gallons.

RPM Is around the same numbers you list so far - 6600s.

ORIGINAL: Maudib

Well I got some fuel through the B60... about a tank... fiddling with the needles and such... unfortunately, my tach was suspect... jumping a bit from time to time for no apparent reason.

The engine was easy to start... it drew fuel REALLY well from dry lines... just 5-6 flips.

It popped after about 5 flips first attempt...and then started after 4 flips. From then on it pretty much started warm on 1 flip. (except whn I got the needles too lean and it wan't getting enough fuel to go...

It seems relatively smooth... I can't say any moreso than the DA50... but quite good...

Transition is very nice.... I must say I AM impressed with the throttle response... Once dialed in it's crisp and without any noticable burbling in the midrange at all...

I tried the 23 3Da first and could immediately hear that it wasn't winding out...I tweaked the needles and played around until everything was where it needed to be.

Again the tach was acting squirrelly (pretty overcast) but it would read about 6100-6200... THis prop actually weighed a little more than the 24x8 so for kicks I tried it... Still didn't wind out... and sounded about and read about the same.

I don't think the numbers are too far off going by ear... I was guessing about 6300-6400... but either way these props are too much load for sure.

I have a 22x8 but the prop bolt bottomed out before I could get it tightened... which really bums me because that leaves me still not knowing where I want to be.

While I was "pie in the sky" hoping I could get somethign decent from the 23/24" props I wasn't really expecting it... if they are getting 7000 with a 23x8 on a tuned pipe... well I just couldn't hope to get very close without one.

Because the props sounded nearly the same and the 24x8 really spun about what I expected... I'd say the 23 3Da might be z pretty heavy load.

So my goal at this point is to get the 22x8 on there and fly it until the engine has a gallon through it, then experiment again with the 23" props... Myabe a regular 23x8...

A lot of this is still somewhat "up in the air" because I really am not happy about how the tach was acting... I'm going to see if I can get a couple others to test against.

Something I did notice was the spool up on both props was really nice... even though they were loading the engine up pretty good. Great transition... With a 22x8 it ought to be smokin' fast spool up... but it needs to be over 7000 rpm's before I'll be truly in love. 7200 and it'll be a powerhouse for this aircraft...

I'd liek to see about 6800 with a "regular" 23x8... but then again... I'm old enough to where my "wants" won't hurt me...