heres another way of looking at it, a motor is just a big air pump its only going to suck in as much air as it can get out

wow...and here all along I thought it was...

V=Bh=pi*(r-squared)*h

Okay, that is the volume of a cylindrical object...but what's that got to do with anything...

I agree with you that the K&N air filter is less restrictive than the stock flame arrestor. I also do believe like you do that their tests with dyno numbers created more hp in their tests.

Tests which were probably rigged with the air filter being the most restrictive part of the whole system. In that case, you definately will notice an increase.

However, I know from experience, that with our 496HO's, the arrestor is not the most restrictive element. It's in the exhaust, intake and ports.

[ 01-24-2002: Message edited by: Baja Daze ]

Baja Daze...

you wrote "However, I know from experience, that with our 496HO's, the arrestor is not the most restrictive element. It's in the exhaust, intake and ports."

what tests have you done to know this?

- jeff

i have a hard time believing that mercruiser would intentionally install a restrictive flame arrestor

I think mercuiser would install a flame arrestor that worked well enough to insure the engine is not going to break down in the warranty period...

Hey Jeffrey, I can only deduce this because I ran the boat with and without the arrestor within minutes of eachother and there was absolutely nothing gained in either rpm, speed or otherwise. That annoying whistling did calm down a bit, though.


[ 01-24-2002: Message edited by: Baja Daze ]

Oh ya, by the way, I have an article from HotBoat that they did tests on the 496HO with a few different modifications. They're most beneficial gains came from the exhaust upgrade. I can e-mail the article to you, if you would like it.

I can't vouch for the 496HO, which I currently have, or how much less restrictive it's filter is than the one's on the 502mag's. But, when I installed the K&N on my previous boat with the 502, I gained approx. 200 rpm (4950 to 5150) and got to know my rev-limiter. This also made the boat run faster and plane easier then it did before with "several people" aboard. This also allowed me to kick up my pitch on the prop .5" and add extra cup to give me 2 more mph on the gps and bring me back to my original stock rpm. Again, not sure how much less restrictive the new 496 arrester is than the 502's stock filter, but for the relative cheapness of the filter compared to other high-dollar high-maintenance add-ons it would be worth the trial. I also suspect we'll see different results mfr. to mfr. because a boat's configuration are so different from one another. I like JeffreyBoy, have the 496HO in a 288 Sunsation so I'll be curious how our particular configuration reacts to it...RexMarine also has the filter for 496's

Rick

[ 01-28-2002: Message edited by: Reckless288 ]