1000 lbs diffrence with the infusion hull


Let me ask you this im turning 30p/5050 rpm @ 80-83 mph gps (depending on load fuel/people/beer/and chop) I would like to get my rpm closer to 5350, I would like to try a set of labbed 28's. Im thinking those might put me in the rev limiter. What do you think?

Man, I wish I had 500efi's!

Well, the rule of thumb is 400 RPM between even pitches. But, sometimes it's less. A labbed 28 would be even more of a gain. So, that would be way too much. A standard 28 would be close. However, it might need to be tweeked to a custom pitch. Bblades was mentioned before and I also would recommend them. Brett has done several props for me and they all worked exactly as expected.

The beer is slowin you down Jimmy, gotta quit takin the whole keg out with you and save some for the evening! lol

Seriously, there's some really good info here http://www.rundquist.com/how_change_pitch.htm about props to check out. Read the other links to the left as well. I agree with Plum Crazy about tweaking them to a custom pitch. A good set of labbed 30's would probably run like 29's or have the stock ones pitched back 1" so you do not have the thin blades to worry so much about and work them from there. Either way would get you real close I would think.

My 31ss has 496 ho's with Bravo 1 28's. I runs a consistant 75 @ 4900 rpm with full fuel and 4 on board. The best was 76 with 2 on board and 1/2 fuel. With the Mercury Racing labbed Bravo 1 28's it ran 77 on the rev limiters. This winter I sent the labbed props back to Mercury Racing for tuning, they expect it should run a consistent 77 at 4900 and we're hoping for 78-79 with light load.

Z06, do you have any mods like exhaust or are your HO's all stock? If they're stock, I'm impressed. You got a fast one.

The exhaust turbulators are removed, K&N filters, amzoil gear lube in outdrives, and Mobil 1 15w-50 in the motors. The K&N filters according to other discussions on this web site just filter better but doesn't result in any performance gain. Keeping the boat bottom & outdrives clean and smooth probably helps more than any of the above mods. Check the idler pulleys on the engines yearly, mine had bearings going bad, that will rob a few ponies on top end.

Stay with the stock 30's or labbed 30's that have increased cuping for bow lift. Our boats need help getting the bow out of the water. I would think labbed 28's would be on the rev limiter and maybe not going as fast. Your current 80-83 is very good. As already mentioned in this thread, Brett at BBlades & Julie at Throttle-Up are prop experts at the top of their game. Either can help you before spending money to go slower and use more gas.

I was originally planning to slip my boat, but that has changed. So, I think I'll try removing the turbulators. I'm already running the Mobil 1 15w-50. Is there really a big difference with Amsoil over Mercury high-perf lube?

Over the winter I had my ECM's reprogrammed because they didn't have a Mercury upgrade way back in '03 and were running way too rich. Hopefully, I'll get some gain there.

This spring I plan to take a day off from work and test 3 prop setups back to back to back. First, I'll see where I stand with my current Mercury labbed 28 Bravos. Second, I'll try a set of standard 28 Bravos. Third, I plan to spin the fastest of those two props inward and see how it runs.

[QUOTE=Plum_Crazy;2829651] Is there really a big difference with Amsoil over Mercury high-perf lube?

The biggest difference is that merc lube isn't synthetic, but costs as much or more than synthetic. I am running Mobil 1 in my drives. Don't know if there is a performance gain, but it is better than any conventional oil.

As GO4BROKE said, synthetic is better. Do a search, some on this site believe there is a gain using Amzoil, I believe anything you can do to make the boat more efficient is good.

Keep us posted on performance after the updated tune, some on here thought they may have lost on top end but it did get rid of the black deposits on the transom. My boats transom is black within minutes.

When you do you speed run, go in both directions (opposites) to cancel out water currents. Take a pencil and tablet to record your RPM's, speed, trim settings, air temperature, and water conditions after each run. I keep track of these numbers on several runs through out the summer, put the info into a spreadsheet and sent to Mercury Racing to assist them in tuning the labbed props. I'll find out this summer if it was worth the time...