Stainless Marine Headers 496 HO
 

Can you all give me some in site as to what I can expect from a 496 HO, in a 247 Baja Islander, if I change to a Complete set of Stainless Marine Headers. My current set up has captains call exhaust. No real problems with the stock set up. Looking for some bolt on power along with sound and looks. Already has a Mark, Precision Marine ECM re flash, Bblades propeller, roller rockers. Boat runs with a REV 4, 25 pitch, 65 mph @ 4780 rpm. All is good just looking for more. Name on the boat is " NEVER SATISFIED ". Go figure.
Thanks in advance.

Exhaust in and of itself isn't going to do a lot for a stockish motor. What it does is unlock the potential in motor. You have to have good exhaust for performance mods. On a boat motor exhaust is a big expense that basically allows you to spend more money to accomplish your performance goal. Without good exhaust ,you have a stone

For $2500 or $3000 what ever they cost i dont think they will give u much more than 1 or 2 mph. Maybe not even that, but they will sound better so u can piss off more sail boaters!!

Go to Full Throttle Marine web site : http://www.fullthrottlemarine.com/ and click on 'HIGH PERFORMANCE PROJECTS and view '496 Mag Dyno Testing & Myth Busting' . The in boat tests were run with Nordic straight wet exhaust plumbing which does not include captains call plumbing (more restrive).

Thanks so much for the replies. I will probably leave it alone. All tho I would not mind the looks and sound. Does anyone know what the actual weight difference is between the stock manifolds and a set of Stainless marine manifolds? Would my ECM need to be re-set?

After tons of reading, they say that spending the money on headers for the 496 H.O. is a waste of money. The stock exhaust has enough flow to let the motor breathe. As for your 4780 RPM, you can turn the stock motor a little harder, 5050-5100. I would think a re flash would bring your max RPM up to 5400 but I think the only person that can re flash our computer is Whipple. Sounds like you should maybe have a couple hundred RPM put back in the prop. Headers may look pretty, but 3K for 1-2 MPH, I would rather spend that on ice and beer.