Harper220

I've got a 2001 28 TD Daytona twin 496 ho's, pretty high drives and no ext. boxes. I'm running stock 30p Bravo's and getting 58-60 mph @ 3400 rpm's, 70-72 @ 4000 rpm's and 93 mph @ wot 4900 rpm's.

I all ready have plans to test the Hydromotive p5x's which should pick up at least 5 mph at mid-range and possibly a few at wot. What else could a guy do to pick up 8-10 mph, new props included, without spending a bundle? I may be asking for too much, but any realistic ideas would be appreciated. Is there any way to pick up 40 to 50 hp with these motors without supercharging or replacing the heads?

I think with 40 to 50 more hp per motor and some prop testing, I could achieve an 8-10 mph gain.

mcollinstn

50 horses per motor should net you 5-6 mph.
Props may find you a couple or three.

Harper220

I'm in the ball park with my calculations. So now, how do you get 50 hp?

Goofy1103

look here

www.raylarengine.com


all goodies for 496 and 8,1

Harper220

I don't want to do the whole replace the heads thing. Too much involved and too expensive for the amount of hp gained. If I were to take that big of a step, then I would just supercharge and get a lot more bang for the buck. It seems like the 496 mags are very limited for lower hp gains in the 50 hp area. I would just like to wake them up a bit to keep the stock reliability.

jdnca1

Boxes and shortened drives...but for what you'll spend you'd be better off putting on a set of whipples........ I think you need to turn more RPM to begin with....reflash your ECM's and prop it to turn 5500......you might pick up 30-40hp that way. You're not going to hurt a mag motor @5500...its just breakin' a sweat I reflashed the 500EFI's in my 28 Tall Deck and turn them 5700. 30 bravo's on boxes.....best of 103GPS on a cool day, light fuel, and 2 people. Didn't get a chance to try hydos but would have liked to....from most I've talked with 28's seem to like bravo props the best......

Fountain38SC

More hp = More $'s. No way around it. Trust me, been there done that. Think about the future with all improvements - don't redo what you just did. Heads or blower are the cheapest way to substantially increase power. just my .02

merlin540

supercharge it and get it over with. a procharger w/low boost will do the trick and they work well on that engine combo seeya

Harper220

Thanks for the input guys... Now, if I decided to say the hell with it and supercharge, what are the pros and cons of Whipple vs. Pro Charger? I know where I can get two Pro chargers for $3600 a piece, maybe even a little cheaper.

I've heard Whipple is instant boost from getting on plane to wot. That would definitely help the Daytona's lousy hole shot. On the other hand, I've heard pro chargers don't do anything off the line and have to hit a certain rpm before the boost kicks in. This to me wouldn't help my hole shot at all. I would think it would be that much tougher to get on plane with a higher pitch prop when propping for the additional hp.

Anybody have experience with pro charger on a 28 twin engine cat? What was the hole shot like?

Also, what octane would you run with the 3.5 psi pro charger kit?

mcollinstn

A 3.5 psi procharger on a stock motor with the M3 blower and the big intercooler can run 89 octane (assuming you run a thru hull exhaust).

Whipple will produce a pretty flat boost curve. If it is setup for 3.5 psi, then you can see 3.5 psi from off idle all the way to top end (with the throttles wide open).

Procharger will build more boost with more rpm.

Making more boost and power at low rpm doesn't help you any if your prop is breaking loose out of the hole.