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View Full Version : 28p 4 blade labed vs standard



Expensive Date
12-05-2009, 04:25 PM
I currently have 28 4 blades on my 292 fastech it has 1.65 drives and at wot 5200 I am running 69.I used to get 71 but my props had a few nicks in them so I had them cleaned up by a local shop and I lost two on the top end.It does come out of the hole a little better though.
My question is I have a chance to buy a set of 28 lab. from a member and was wondering if I would see any more top end.What are the advantages and disadvantages of lab vs standard.


Thanks

jeffswav
12-05-2009, 08:25 PM
I currently have 28 4 blades on my 292 fastech it has 1.65 drives and at wot 5200 I am running 69.I used to get 71 but my props had a few nicks in them so I had them cleaned up by a local shop and I lost two on the top end.It does come out of the hole a little better though.
My question is I have a chance to buy a set of 28 lab. from a member and was wondering if I would see any more top end.What are the advantages and disadvantages of lab vs standard.


ThanksI am not the prop expert but I know the basics from experence. There are things you can do specifically to the prop to make it perform better on your boat. If you need bow lift you can put extra cup in the tips. If you need stern lift and more RPM you can remove the cup. You can ballance the prop and thin the blades to pick up speed. There are also things you can do to the prop to lower prop slip. It depends on what they did to the prop when they labed it. Sound like they changed somthing on your prop that made you loose speed.

Expensive Date
12-05-2009, 08:31 PM
I am not the prop expert but I know the basics from experence. There are things you can do specifically to the prop to make it perform better on your boat. If you need bow lift you can put extra cup in the tips. If you need stern lift and more RPM you can remove the cup. You can ballance the prop and thin the blades to pick up speed. There are also things you can do to the prop to lower prop slip. It depends on what they did to the prop when they labed it. Sound like they changed somthing on your prop that made you loose speed.

It was not labed just cleaned up so its probably a little smaller.The new labs I am looking at are labed from Mercury.

jeffswav
12-06-2009, 12:17 AM
It was not labed just cleaned up so its probably a little smaller.The new labs I am looking at are labed from Mercury.When you lab a prop it should be setup for a specific purpose to work correctly. Just because it is labbed by Merc does not mean it will work well on your boat. I know more about Baja's, they like a lot of cup on the tips to get the bow up and reduce the slip. The prop should be "Labed specifically for your type of boat". I have seen Merc Lab props with the tips hacked off, this may work well on a stepped hull but does not work on a Baja. Just do your homework and do some on water testing to find out what works best.

Expensive Date
12-06-2009, 12:46 AM
Thanks

Griff
12-06-2009, 03:43 AM
You would probably be hitting the rev limiters with the Merc labbed 28's. I would have yours reworked by BBlades to your application.

HiZ
12-30-2009, 09:36 AM
Depends on how the labbed props were customized.
Check with the shop that did them to find out what was done.
Or if you can't find out have BBlades look at them. They can measure and tell you Exactly where you should be with the props in their hands.
It's all in the labbing
Can you put them on your boat to "see" where they are exactly

Chris
12-30-2009, 10:09 AM
Labbed props typically need more pitch. And by virtue of the blades being thinner, they're more prone to breakage. Labbed may not be the best approach. Dealing with someone very knowledgeable on prop selection will probably yield you the best benefits.