vegas daytona

Gave myself and early gift, IMCO 2" Shortie and the afternoon off. I just got back from Lake Mead prop testing and everyone around the great lakes and call me a wimp, but, its was "Freaking Cold" for a transplanted So Cal surfer.

I need some help with the props. I ran my old 24" Bravo 1 with good cupping and also tested a labbed 26" Bravo 1 thanks to Kevin at R&R Prop Shop in Henderson. Before the shortie the 24" ran 68mph at 4900rpm. Today the same 24" ran 71mph at 5200rpm. I think I could have got another 100rpm but didn't push it. The labbed 26 ran 72mph at 5200rpm. I still had a good 200rpm more but again didn't stay there long enough to get a gps reading.

I lost 1-2mph below 4000rpm with the 24" due to the shortie. Lost another 2mph with the labbed 26".

How can I drop 200-300rpm off the WOT and get my cruise speed back to where it was or better? Cup the labbed 26" bravo 1 or go to a 28" Bravo 1.

To everyone, Merry Christmas and for those back east, stay safe in the storms.

vegas daytona

Forgot to mention that I am running an 24' Eliminator Daytona with a built up 454 making ~475 to 500HP. I'm looking for the best cruise speed at 3500rpm to 3800rpm but still want to run 72mph+.

throttleup

Is the 24 Bravo 1 stock or has additional cup been added to the stock prop?
Does the 26 lab have much cup in it?

Cup will get your cruise speed back but at the expense of top end speed.

What WOT rpm does your motor need to run at?

A five blade prop will get the cruise back and I would also expect an increase in top end speed as well. Your rpm and speed numbers indicate that the boat may do quite well with a 5 blade prop now.

Any questions please give us a call.

Matt

vegas daytona

Thanks for your reply.

The 24" does have some extra cup added and the 26" has been labbed with very little cup. I am not getting any blow out getting on plane with eather prop. They both are holding very well

The engine is a stock Mark IV mag bottom with full roller valve train, dart intake, 800-holley, GM rect. port heads mild cam and Lightning headers. Prop is set 3 1/2" below hull. I would guess it wants to run at 5200 rpm but I would rather prop it alittle lower, say 5000rpm to 5100rpm to enhance the cruise speed and save the lower end.

The boat runs best with the prop set up for bow lift. Since I have no problem getting on plane and the boat wants bow lift it seems like a four blade is a good choice. Would adding some cup increase my lift and lower my slip numbers at mid range? If I add cup to a labbed prop will it run the same as a stock prop. The reason I ask is that there is a stock 26" Bravo 1 I could demo. I would think a five blade would provide less lift and more drag. But I'm no expert and that is why Im asking.

Money is a factor but not one I cannot overcome for the correct prop.

Thanks for you input.

throttleup

We have put the P5X prop on quite a few 24 Daytonas and in every case both the top end and cruise sped has improved. The handling of the boat also improved as well as acceleration.

If you put cup in a lab prop it will be pretty close to a stock Bravo 1, with all other aspects of the prop the same. The cup will reduce the slip and improve the cruise speed but at the expense of top end speed. That is why the 5 blade has been so popular. It improves the cruise speed and will maintain the top end, in many cases improve the top end.

There are different 5 blade prop designs on the market and we have found that the P5X tends to lift the boat. The rake angle lifts the bow while the additional blade lifts the stern causing the entire boat to lift thus reducing the wetted surface area.

The Bravo 1 will run just fine on your boat and can perform well. It just needs to be adjusted to meet your goals.

Matt