I just recently installed a set of Lightning headers on my 496HO I cut off the 4inch reducer and used 5inch hose to connect to a set of 5inch tips. I have the Volvo version and the factory manifolds were as bad as the old merc style. I had to fab some brackets for the oil filter housing, ecu and relay box other than that they fit perfect. I bought them slightly used with no leaks.The guy I bought them from had them on a 500efi. I haven't had it out on the water yet but I will post my result as soon as I can. Season is over here but I don't know if I can wait till spring I might just have to put on my snow suit a go freeze my tail off .

What kind of boat do you own? I'd really like to hear if you gain anything. Put on your snow suit and let's hear about it...

CMI and others make some rather "optamistic" claims as far as hp gains. Just MHO.

Well let me start with the fact that Jan at Lighting is a first class guy! I have done business with Lighting since 1991. The first set I put on a 25ft Checkmate 454 blower motor with a speedmaster, with that set up the headers rendered a 700 RPM gain. that set is still being used, I have sold that boat here in town, and the headers are still working fine !! no leaks Internal/or External. I'm on the fouth set since then, four separate boats and have experienced very impressive HP gains! Easy to install (Custom made for your boat )

Sorry ! I hit the wrong KEY!! But to finish! On your motor I can't say how much HP it will gain But I would say call Jan he will be honest on the expectations!! Good Luck

Yes they do. But the poster was referencing headers with a $1799 price point. That's not the all stainless version.

Will e tops work on the 496?

Hey Todd did the hatch scoops get some more mph?

Harper 220 I have a 26 Corsa

Not really sure on top end. I rarely run at wot and the cats have so much room for airing them out that I never get a chance to tweak every little bit out (that could get you killed at LOTO). As far as breathing better, yes, much better... I picked up 2 mph at any given mid range rpm.