Harper220

I have a 2001 28 Daytona with 496 HO's, no ext. boxes, but what appears to be very high drives. Right now I run stock 30p Bravo 1's and 1.36 gears. Here are my numbers:

3100 rpm = 50 mph = 22% slip
3500 rpm = 60 mph = 18% slip
4000 rpm = 72 mph = 14% slip
4900-
5000 rpm = 93 mph = 10% slip

I would like to improve my hole shot, (mid-range most important) and top end. The Hydro p5x's ($2000) look promising...

But,
A few other options that I've been thinking about: Whipple Stage 2 kits ($795 a piece), which should ad roughly 35 to 40 hp and 35 ft. lbs. torque per engine. Nose cones? (cheap) Or have my 30p Bravo 1's re-worked.

I'm looking for answers or opinions based on actual trial and error of others that have gone down this road. I would like to know if one or a combination or all of the listed options would be the best thing to do to achieve my goals? If I have left any ideas out, let me know. No Superchargers please.

SkiDoc

iTrader: (4)

Harper, I know my Daytona did not work well at all with the Hydromotive props, they raised the stern and made it tough for the bow to rise. The stern would actually twitch side to side. I know that the P-5 is different, but I spoke to Throttle-up and Julie said that it is still a transom lifter. I imagine holeshot and midrange would be improved, have my doubts about top speed. They do have a demo program though. Or call Kenny at Eliminator, he'll tell you. Most agree it takes 20HP/MPH so the Whipple might add 2-4mph, lab finishing will give you 2 mph. As you can tell, I'm trying to figure out the nose cone thing myself.

rbtnt

My friend and I both have 28 Daytonas with NA engines. His X is a little lower than mine and he can run P5s and I can't. Too much propoise on smooth water for me. Mine even porpoised a little with the Quad IVs. We are both running the engines 5700 - 5900 which is about 1000 - 1200 rpm above peak torque.

We both have boxes and found that we change ~1 mph for each 13hp.

My friend ran one drive with a nose cone and one without, when he was waiting on a propshaft a couple of years ago. The drives ran about the same up to 85 mph, then the one without the nose cone started increasing rpms a lot faster than the one with the nose cone. I think he only ran it up to 100 mph because of the difference in rpms.

We have seen a varienty of Xs on the 28 Daytonas and it makes a big difference. They also mount the engines at various distances apart. Mine are almost 2" closer than my friends, which results in a higher X and closer to the tunnel.

Turbojack

It is hard to increase takeoff time & top end at the same time. When you work for top end you will loose takeoff time unless you have plenty of power & then the bravo is going to be the problem

FASTCASH

Harper, I Currently Run 30p Hydr P5x On My 2003 28 Td. My Setup Is Twin 511 Bowties @620 Hp, Bravo Xr 1.36 On Imco Boxes, Imco 2" Shorties With A 1" Spacer. I Ran The Setup With The Hydros Without The Spacer And The Stern Had Soooooo Much Lift That The Bow Plowed At All Speeds And Trim Angles. When The Spacer Was Installed The Attitude Of The Boat Was Perfect And The Boat Ran 6mph Faster Than It Will With 32p Labbed Bravos. I Originally Had 496 Hos In The Boat And Ran 30p Labbed And Non Labbed Bravos. The Labbed Prop Ran 2 Mph Faster And The Non Labbed Prop Planned Faster. It Will Be Difficult To Plane With 496's And P5x 30p. I Think That 93 Mph Is Awesome With The Power You Are Running And If The Boat Comes Onto Plane Well I Would Not Change A Thing. Good Luck!!!!!!!

blownboat

Fast cash,what are your speed numbers now,and do you like the p5x.

Harper220

Fastcash- I was thinking about the 27p or 28p p5x, since I have much less power. I think I could turn those and plane fine. I don't have shorties either, so trim shouldn't be a problem. I am getting pretty good #'s currently with the Bravo 30's from the sounds of it. The p5x's would have to be significant in order to justify a purchase. I will try them this spring. Just out of curiosity, what were your #'s when you were running 496 ho's and what are they now? I would think with 620's, you'd be running at least 34 bravos. thanks

throttleup

Remember when calculating slip with Bravo I propellers you need to decrease your pitch size by 1 inch. So Harper220 your slip is 8% at WOT. Not bad for Bravo I propellers...almost to good...makes me wonder!

Julie

FASTCASH

Harper,
The Boat Ran 90mph With The 496's, Bravo 1 30p Non Labbed , Extension Boxes And Xr Lowers. 92mph With The Labbed 30p Bravo 1. Once We Installed The 620's, The Boat Ran 108mph With The 30p Non Labbed Prop And The Xr Lowers. The Problem Was That The Blades On The Props Were Breaking Off At The Hub With The Xr Lowers When The Boat Was Running Over 100mph. The Switch To The Imco Lower Fixed The Problem And The Boat Ran 111mph With The Non Labbed 30p And Now Runs 117 With The 30p Px5. The Boat Planes Better With The Px5 , Accelerates Harder And Feels More Solid In The Turns. I Really Believe The Stern Lift Helps The 28 To Fly Better Once We Got The Lower Unit At The Right Height. I Do Not Believe That My Boat Could Plane Off With A 34p Bravo Because It Still Planes Very Slowly With A 32p Labbed Bravo 1.

jdnca1

Fastcash:

Sweet results. Do you know where your drives are in relation to the bottom of the boat with your current set-up off hand? I have never measured mine precisely, but they are very close to even to max 1" below on boxes and standard length (leading edge) lowers. Best I ran was 103 GPS with stock 500EFI's (raised rev limiters) turning 30 bravo's IN 5700. Me only and very light fuel, 28 Tall Deck.

Do you get a lot better bow lift with the p5x vs the bravos? Did you try any clever style hydros like the Q4 or the straight P5? I have to trim mine to the moon currently to carry the bow so I'm positive the drives need to go higher.