Should I get the prop's labbed??
 

I am running a Scarab Panther (twin 502's, 550hp, TRS) on Mirage Plus 25's at about 4800 - 4900 WOT with full load of fuel, and 4 passengers. I can get 5000 rpm's with less fuel and less people. I want to be turning about 5200 - 5300 rpms.

I also have a set of 25p Mirage props that have given a best of 76 mph but cruise speed was only 45 mph. The RPM's with the Mirage' was slightly higher at 5300 rpm's WOT. With the 25 Mirage "Plus" the cruise speed is 51 mph with a top speed of 74-75 mph. I really like the Mirage Plus better though. They bite better, and the cruise speed is better.

Cruise speed with the Mirage Plus is about 51 mph at 3600 rpms. I don't want that to change, but would like it to get better if possible? Will labing make me loose any cruise speed?

What would the dammage be??? $$$$

What are you're opinions?


__________________

I had a Panther in 1987, that boat didn't run well with any of the Props you are running. I ran Lazers, and a pair of Vipers. The mirages didn't give me enough bow lift. Call Dennis Cavanaugh at Mercury Racing. He will me glad to give you some recomendations. Nobody is better then the "Top Man" at Mercury's Prop Lab. If you need his number let me know.

Philip

Philip,

Can you email me his number.

[email protected]

Thanks

Panther

I know there must be some other opinions out there as well??

Philip,

To overcome the tendency to bury the nose I switched the drives to change the prop rotation. Now I have a lot of bow lift.

Panther

I tried to e-mail you the Info. but it came back, address N/G. here it is,Frank,
Dennis Cavanaugh Mercury Racing this number is his number at his
desk. 920.924.2037 Dennis is the man to
talk to. . If you want to call my # is
973.214.9686

Philip

Phil,

Thanks for giving me Dennis' phone number. I just got off the phone with him.

He confirmed my thoughts of loosing cruise speed with a labbed prop. He said that I will definetely loose some cruise speed, and thats not what I want.

Although what he did recommend was that I test a 27P Mirage Plus and see what the rpms are, which should be about 4700 rpms. Then he recommended getting the 27P Mirage Plus props labbed and I wont loose any cruise speed and gain a little top end.

Thanks againk,

Frank

the biggest problem when you lab finish a 3 blade prop it tends to give you a lot more slip out of the hole and can cause you to blow the props when trying to come on plane

I have a Panther as well. Original equipment was 365hp mags running 25 pitch Mirages at 5000. This was before I owned the boat, but I believe the prior owner when he said he got low seventies with the boat. For various reasons, the boat now has mid three hundred horse power engines and with the same props gets 66-68mph GPS at 4700rpm. Am working some engine changes over the winter that I hope will get me in the low four hundred horse power range. With that I expect to go to a 26 four blade or a 27p 3 blade. Target speed is 75mph. Can't really understand why at 550hp you are not at 80+. Only diff between you and I is trs vs bravo.

When I contacted a prop labber (can't remember who) they said older heavy boats like the Panther were not good candidates for labbing due to prop flex from the thinning. I left it at that.

I guess that fact that you have trs drives makes you need bow lift, which I alway thought a mirage 3 blade was good for. Me with the bravo, well I have plenty of bow lift already with the bravos and the need stern lift of a four blade (I think).

BT :cool:

Sounds like the Rev4 prop might be a good choice. They seem to have similar top end to the Mirage but much better cruise. Lots of lift stern and bow as they will hold more trim. Might be worth a test drive.