I do not lock the brakes and measure static, but

here are my numbers

2180 at initial takeoff roll.
2300 at Vy (105 kts)
2850 down low WOT (185kts TAS)
2780 WOT 8500'DA (182kts TAS)

Pitch is 74" on the new layup.

It just came back from Craig today after being re-pitched to 75". According to Craig, it will to reduce top end RPM by about 50, but not reduce low end by much of any due to torque curve of engine. Will bolt it on and try it on Friday.
 
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My Catto numbers

7A, SJ cowl, plenum & pants, 180 hp Superior, Catto 3-blade, repitched to match my performance.

climb @ 110-115 KIAS =>2150 approx
WOT @8000' DenAlt = 2750-2770 (175 kts KTAS)
Craig says normal spread between these should be about 500 rpm.
 
200 hp O-360, 3 blade Catto. Around 2200 rpm or so at lift off. Never measured max but it is over 2700 rpm

Checked today and it was 2250 at lift-off.

Dale, should that improve your cruise speed? I suspect that I need more pitch on mine after the engine rebuild but don't know if it is worth the expense and downtime.
 
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2200 to 2780

Asked Craig to prop mine for 170 HP, as I have a carbureted, angle valve O-320. He hit it right on the head, as I get around 2200 on takeoff, rising to around 2400 in a normal 135 mph climb, and 2780 at WOT and 202 TAS. This is on a -6 with the old wheel pants.
Ron Voss
N642R
 
Ours is 2200 also.....

...on initial start. It turns 2700, leaned, at 7500 DA, just like Craig said it would. It also beat Van's numbers by several MPH, as Craig said...202-203 TAS.

BTW, with a FP prop, my RV will still climb near 900 FPM at 165 indicated! That's because the revs are higher at that speed...higher revs, higher horsepower,

Regards,.
 
2640 is the max RPM I've ever seen on my Catto 66 x 76 with my Aerosport IO-360. On takeoff it makes about 2220.
 
Cruise speed

Ron Lee said:
200 hp O-360, 3 blade Catto. Around 2200 rpm or so at lift off. Never measured max but it is over 2700 rpm

Checked today and it was 2250 at lift-off.

Dale, should that improve your cruise speed? I suspect that I need more pitch on mine after the engine rebuild but don't know if it is worth the expense and downtime.
Click to expand...

Ron,

My prop was actually pretty good for my AC. Climb was really good. I had the plane in the paint shop so took the oppertunity to send it in for prop guard tape. Otherwise I may not have. BTW, he turned it around in a week and did not charge me for the re-pitch. Craig is tops in my book.

I do not expect WOT top speed increase. In fact, since I will be turning less RPM, I will probably make a little less power and get a little less top speed. I am just trying to drop the cruise RPM a bit and save a little gas. Even at 12,000DA, I have lots of throttle sticking out at 2700RPM. I would like to be able to run 12,500 WOT and be 2700RPM or a little less.

I think you want to be able to turn more than 2700 down low, but if you can get to the point that you can cruise high at WOT any stay below your comfort level for sustained RPM, then you will reduce pumping losses and save fuel.

I hope the re-pitch is an improvement.

Will find out tomorrow.
 
Mine was a 66x76 3 blade on an o-360 and I saw numbers like everyone else. What I didn't like was having to turning up to 2800 at wot on my new motor to see those numbers. Plus, on decent, the prop didn't really provide much braking power. That coupled with a slick airframe seemed to make getting down from cruise altitude take forever.
 
More Data

I get around 2220-2230 at lift off and can spin mine up to 2760-2780 at wot and 8k density altitude. Craig tells me you should see 500 to 550 rpm difference between these two points.

Cheers,

db
 
I guess I need more data

I seldom run over 2600 rpm for noise issues. I have considered going high (16500' or higher), full throttle to get an RPM. Drop a thousand feet, record the data and so on. From that I should be able to determine max RPM at 8000' since I suspect that it is somewhat higher than spec'ed due to HP improvements made after I got the prop.

The point is that I need to know what improvements it will make before I take the prop off. However, with the turnaround being a week or so that makes it easier to do it. I just went two weeks without flying after flying 16 hours in three days.
 
hevansrv7a said:
7A, SJ cowl, plenum & pants, 180 hp Superior, Catto 3-blade, repitched to match my performance.

climb @ 110-115 KIAS =>2150 approx
WOT @8000' DenAlt = 2750-2770 (175 kts KTAS)
Craig says normal spread between these should be about 500 rpm.
Click to expand...

H.Evans.
What is the repitched number that you went to. I am using the
same setup.
Thanks,
 
Thanks for all the info. Today I did a static run up max power not moving 2330 RPM at 2000 ft msl 2650 RPM full power at 5000 ft 2645 RPM. My engine is a ECI kit , high comp. pistons with cold air ind. AFP F.I. and LASAR ign.
 
Let's turn this around...

Hello Catto Lovers,

Let's look and the idle and landing pulled throttle RPM's. IOW's what RPM do you see sitting at pulled idle with engine at takeoff temp? Then what RPM do you see on final windmilling throttle pulled all the way back in landing configuration say 25-30 degrees flaps? I'm going to back off the idle on my plane a little and just looking for numbers for a spread sheet to work with to find that sweet spot.

I PM'ed Mel on this issue as we have a close engine/prop setup, but I guess he's on vacation again. :D
 
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LifeofReiley said:
Hello Catto Lovers,

Let's look and the idle and landing pulled throttle RPM's. IOW's what RPM do you see sitting at pulled idle with engine at takeoff temp? Then what RPM do you see on final windmilling throttle pulled all the way back in landing configuration say 25-30 degrees flaps? I'm going to back off the idle on my plane a little and just looking for numbers for a spread sheet to work with to find that sweet spot.

I PM'ed Mel on this issue as we have a close engine/prop setup, but I guess he's on vacation again. :D
Click to expand...
I'm here. Just really busy. Sorry. My idle RPM is about 650. Static is around 2250. Max RPM st WOT/8000' is 2750. On landing approach, I have no idea. I'm looking outside.
 
Mel said:
I'm here. Just really busy. Sorry. My idle RPM is about 650. Static is around 2250. Max RPM st WOT/8000' is 2750. On landing approach, I have no idea. I'm looking outside.
Click to expand...

Hey Mel,

I figured you were back on a boat cruising to some other part of the world. ;)

Thanks for the numbers!
 
LifeofReiley said:
Hey Mel,

I figured you were back on a boat cruising to some other part of the world. ;)

Thanks for the numbers!
Click to expand...

Nope, just got a lot going on. Lots of E-AB inspections.
My wife's family reunion this Saturday. Then in a few weeks, my high school reunion. Then a few weeks after that our annual EAA Chapter Fly-In picnic. All right here at Short Stop. Lots of prep.
Then not too far down the road the RV-12s will start coming out of the woodwork and hopefully I'll be real busy with E-LSA inspections.
Ain't retirement wonderful? I never worked this much when I was employed.
 
DanLandry said:
We've matched numbers over the last 3 years. Same pitch, I'm getting 2640-80 rpm.
Click to expand...

Dan and Scott, I'm still doing my phase 1 and don't have wheel pants or gear leg fairings. I'm getting about 2570 max RPM, but I figured it was just because my airplane is draggy. Do you think it's possible that you're not getting full RPM's due to drag from something?
 
My idle rpm is 420 and when we lowered it it really helped control descent on final. Don't know what rpm is on final--never really looked. I get 2180 on takeoff and 2780 WOT at 8000' DA. Speed at that altitude is 192 mph, somewhat better than Van's projections for a 160 hp 9A. It is faster higher up, but I haven't really nailed that down exactly. Close to 200, but not sure. I am surprised that it is faster higher up, but Craig wasn't. P-Mag's seem to make the difference up high, but I can't be sure.

Bob Kelly
 
videobobk said:
My idle rpm is 420 and when we lowered it it really helped control descent on final. Don't know what rpm is on final--never really looked. I get 2180 on takeoff and 2780 WOT at 8000' DA. Speed at that altitude is 192 mph, somewhat better than Van's projections for a 160 hp 9A. It is faster higher up, but I haven't really nailed that down exactly. Close to 200, but not sure. I am surprised that it is faster higher up, but Craig wasn't. P-Mag's seem to make the difference up high, but I can't be sure.

Bob Kelly
Click to expand...

Hi Bob,

Is the 420 RPM idle with the Catto Prop, have you ever had the engine want to die on final? I have a friend that went from a Sensenich to a two blade Catto and this happened to him. I take the difference in 42 lbs spinning and 18lbs spinning...??? It did get his attention. :eek:
 
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lostpilot28 said:
Dan and Scott, I'm still doing my phase 1 and don't have wheel pants or gear leg fairings. I'm getting about 2570 max RPM, but I figured it was just because my airplane is draggy. Do you think it's possible that you're not getting full RPM's due to drag from something?
Click to expand...

You will not get full RPMs until the plane is cleaned up.
 
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LifeofReiley said:
Hi Bob,

It the 420 RPM idle with the Catto Prop, have you ever had the engine want to die on final? I have a friend that went from a Sensenich to a two blade Catto and this happened to him. I take the difference in 42 lbs spinning and 18lbs spinning...??? It did get his attention. :eek:
Click to expand...

Never. I don't pull it back all the way on the ground (usually) but the windmill effect keeps it plenty high on final. Also the P-Mags cut the advance back at very low rpm so it idles very smooth.

Bob
 
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