MESABALANCING

Bob the Gils we have are new and have the proper warranty we need for our packages I know there are other exhaust out there which out perform the gils though the Danas are not one no matter what anyone says the runner cross section will not allow for adequate flow for any n/a engine over 500-540 cubes. I personally don't know the manifolds you had were the subject of the damage of the previous engines because the pipes are also leaking. Something we also need to think about is we've found 7mph in props and exhaust we can be slightly down on power but I still think there is more to be found with a moderate chop I know we can go in the speed were looking for

Elite Marine

Fuel System was (2) 3/8 lines to a 1/2" tee into the Wix Seperator then to the Aeromotive 1000 Red Pump then through a Peterson High flow Filter to the rail. Actual parts as on the dyno. Fuel pressure is monitored with a mechanical gauge next to a boost gauge...all is well with the system and boost reference.

Blower hose arrangement is on the engine, not changed from the dyno.

Bravo Drive 1.5 Ratio (verified)

Ran 25P, 27P, 29P Props.

Ran 82.8 with a 25P Mirage Plus @ 5400 RPM on the limiter

Ran 84.7 with a 29P Mirage @ 4700 RPM

GPS Batteries died while running the 27P

I really do not think its a prop/boat issue. As others are running the same boat in the low 90's with 600+ HP. The motor was in my 24 during this testing, not the 28 that it is in now.

WETTE VETTE

How many RPM's with the 27? The differance between the 25 and 29 seems about right to me. The 27 is likely your correct prop. It takes some pretty healthy power to pull a 29 to 5400 RPM in a 24' vee. I wouldn't expect 650 to get it there. Probably not the answer you wanted to hear and I could be wrong. Good Luck!

Craig

samracer

well i am just getting into this powerboat thing, but for starters i know that with race car headers, you can print any number with different headers, some will be less hp and tq and some will be more hp and tq, but to truly find the best set you have to go test them out, because one that is down on power but will have faster mph and et times

now i know that is for cars, but im sure it could hold true with boats as well

it has to do with header length, and size, and trying to controll the gas pluses

my advance is to find out what other boats with the same engines are running and start there

Stormrider

If you take these #s and put them in the prop slip calc, the # seems very low. Just an observation.

prop slip calc.

dana marine products

Not to start a war - but I feel the need to post facts about our exhaust systems. Check the following dimensions, they are fact.
Surface area of primary at the head -
3.062" DMP Manifold
2.759" 1 7/8" tube header

Surface area of primary at collector
2.785" DMP manifold 4 ports collectively 11.14" area
8.9416" I.D. Tube header with a 3.5" I.D. pipe 4" O.D.
11.787" I.D. Tube header with a 4" I.D. pipe 4.5" O.D.

Normal tube header runner length is 15.5"
DMP exhaust have a 27" long runner length
Our primaries carry through the riser flange.

Exhaust scavenging is not well known in the marine industry. The team of nascar exhaust engineers who designed our risers would agree that alot of power is lost through exhaust. Our exhaust systems have been run successfully on several high horsepower applications, the most recent is a 920 HP blown motor in the new 27 foot Joker boat from Dana Boats. Westech dyno'd motor. We also have a boat going together with a 1200 HP PSI blower motor that was dyno'd by Paul Pfaff. That's just to name two. I have not one complaint about our manifolds losing HP.

GLENNS

Its my understanding that on blown applications the scavenging effect of the header is not nearly as important as it is in NA applications. Would you agree??????

dana marine products

Absolutely agreed, although it has no negative effect.

otis311

Ill use your phrase "not to start a war". But you really put a screwing to me on that exhaust. I called and talked to Dana himself and asked him if that exhaust was a dry setup and was assured by him that is was, I placed the order thru Trick, paid $350.00 for shipping only to recieve something that wasnt a dry set up and the finish on the manifold had scratches on it. Las and Fred were both given a difficult time when I went to return your product and to top it off I had to pay another $200.00 of my own money to ship back your mistake. Im out over $500.00 because you misrepresented your product and then gave me an attitude. I dont care how much HP loss you claim or dont claim, Im pissed off on how you handled this whole deal. This whole story and series of events can and will be backed by Fred and Las

I would absolutly love to hear back from you and see if you want to correct this problem.

Bob Scanlon
518 361-6521 24/7

otis311

The pipes are being made by Stainless Marine

$3200.00 I dont know much about nothing, but that price is real tough for me to swallow