Re: Removal of 496HO restriction plates
 

He did say a 15 hp gain without them. I took mine out last spring and not sure if I noticed much, but at least good to know in my head that I've freed up 30 hp on twins. :D

Re: Removal of 496HO restriction plates
 

Yeah,this is getting a little confusing,I was referring to the guys math where he figured 40 hp over stock from eddie marines cast manifolds claim of 10% gain in the other thread I was refering to. Raylar was very skeptical of that big of a gain from 2000$ cast manifolds and I garnered from what he was saying that they were definately comparing there gains to stock un-modified factory manifolds. I wasn't referring to the cmi's,BUT, I will say if I had a 496 ho in something I'd just spend the money and get the cmi's for there very impressive gain over stock,it sounds like they really put some development in them,Smitty

Re: Removal of 496HO restriction plates
 

Picture of plates

http://www.offshoreonly.com/forums/s...d.php?t=122974

Re: Rework of Merc 496 manifolds!!
 

We kind of decided to go ahead and offer a fix for the Merc 496 manifolds that some not so deep pocket boaters can afford. We have done a lot of flow bench work on the Merc 496 stock aluminum manifolds on our heads and we have developed a CNC program where we can run existing manifolds thru our 5-axis CNC machine and add some pretty nice cfm flow enhancements. This should also be very helpful to the guys worried about warranties and those adding superchargers and other power upgrades. We will be offering these reworked manifolds on an exchange basis at a very affordable cost. I will post the actual pricing very soon. Any body who has some stock manifolds around email sales @ raylarengine.com and we will most likely be buying up a few sets to get ahead of the demand. Again, Raylar tries to meet the simple needs of 496 owners without "deep-pockets"!!

Regards,
Ray @ Raylar

Re: Rework of Merc 496 manifolds!!
 

What kind of hp gains are you seeing with your manifold work along with removal of the restrictor plates?

Also how much for the exchange on a set?

Re: Rework of Merc 496 manifolds!!
 

Sounds like an interesting proposition. How are you doing the porting??? Extrone Honing would probably work well. Please keep us posted summer is almost here, that would be nice to get done before the season. Best part is it will be a simple swap over, no parts relocation...

Re: Removal of 496HO restriction plates
 

The porting and recontouring is done by 5-axis CNC maching as I previously mentioned. Extrude hone can not properly open the port at just ideal locations and unless you've priced it lately it's way to "Damn Expensive". You guys really like to come up with ways that waste money don't you? Yes these manifolds will be ready for interested parties in April.

Ray @ Raylar

Re: Removal of 496HO restriction plates
 

Ray,any idea of HP gains and cost of rework to the exhaust for those of us who would like to wait until April for your product. Also would a ECM reprogram be a good addition to the header rework?
Thanks, Tony

Re: Removal of 496HO restriction plates
 

Again, how about hp gained and exchange price?

Re: Removal of 496HO restriction plates
 

Nice Ray! Keep it coming. Also congrats on the Powerboat Magazine article on your new 700hp N/A beast. Did GM design a whole new block for you or just overbore the block for you?