What's it worth to upgrade to a Hartzell Scimitar prop?

[mikey757]

I have J model that had a 3 blade Mac on it. It always had a lot of vibration despite being balanced by the previous owner. It started leaking a lot of grease and was going to need an overhaul. I had Stallings put on a 2 blade hartzell top prop and sold the 3 blade. It was expensive but it is smooth as silk and I gained 6-8 knots in cruise depending on altitude.  Also had an A plus experience with Stallings.

[AndreiC]

11 hours ago, Echo said:

Andre, if the prop is a search for speed, the issue may be that your plane is post 1968 "clean wing" Mooney production and is consisered a "dirty wing" due to non flush rivets done by Butler and Republic in a cost savings venture.  Per Coy Jacobs in his book backward tails The later Butler and Republic aircraft with dirty wings can be several knots slower than earlier flush rivet retractable step clean wing Mooney aircraft.  This speed deficit can easily be remediated with cowl, windshield and other 201 type mods per Jacobs.

Yes, the prop switch would be mostly for speed -- as I said my prop is fine as is, and it is quite well balanced, I don't feel much vibration. (But then again, maybe I don't know better.) From reading things other have said, the main things slowing down my plane are the prop, the dirtier wing, and lack of speed mods. I hear of people getting 150-152 kts in normal cruise at 8.5 gph or so (in earlier model E's with the 2-blade prop). That is far from what I see; the best I can do is 143 kts at 9.3 gph.

There aren't many mods I can or want to do: the windshield, which would be the biggest improvement, is expensive and kills the access to the radio bay, so many people say better not to do it. Getting the wing cleaned up is not doable. So the prop was the only big one I could hope to do. I see above someone saying they got 6-8 extra knots. If that was the case it would definitely be worth it for me. But if I only get 2 knots out of it, meh. A bit of my question was about what I could hope for.

[Echo]

16 minutes ago, AndreiC said:

I hear of people getting 150-152 kts in normal cruise at 8.5 gph or so (in earlier model E's with the 2-blade prop). That is far from what I see; the best I can do is 143 kts at 9.3 gph.

 

I personally don't live in an alternate reality.  I find the majority of speed claims amusing.  Personally I liked my three blade and I like the two blade.  I would not change either unless I had to.  I really liked your E when I say it in Madison.

[carusoam]

On 8/21/2025 at 7:09 AM, mikey757 said:

I have J model that had a 3 blade Mac on it. It always had a lot of vibration despite being balanced by the previous owner. It started leaking a lot of grease and was going to need an overhaul. I had Stallings put on a 2 blade hartzell top prop and sold the 3 blade. It was expensive but it is smooth as silk and I gained 6-8 knots in cruise depending on altitude.  Also had an A plus experience with Stallings.

Fantastic report for Our Prop Guy! @Cody Stallings

thanks for sharing…

Best regards,

-a-

 

[Echo]

The Southwest Texas windshield mod mimics the J speed slope screen, but retains access to the avionics through left/right panels.  It is just ridiculous that this STC does not continue to be available.  I HATE that so many great mods are locked up because of legal crap.  To what end says I?