RDatTN

I have a 27 fountain fever with 496 HO. Would like to get more performance out of the engine. Would also like to not sacrifice reliability and durability. I would like to get an additional 5-10 mph at top end. Any suggestions?

t500hps

Raylar had a thread/post about a build up of this motor to around 530hp. That would be enough HP to get the speeds you desire. The testing done appears to suit your needs. I'm not familiar with it, but the info in the thread looked promising.....good luck.

Raylar

We just completed another customers boat as a project boat and had better success than most 496 owners have imagined. The boat was a 28 Ultra cat. Its a big cat with a single 496HO with the boat weight about 5400lbs. The owner GPS'd and timed the boat with two people and 140 gallons of fuel in frtesh water at Lake Havasu, Arizona. The boat tested at 66.4mph to speed at 5100 rpms and took 15 seconds to plane from zero mph with a labbed 24P Bravo 4 blade prop. The BP103 kit was installed by our dealer Absolute Marine in Havasu and the boat was retested with same fuel load, 4 people aboard this time and under same condtions. With a 28P stock Bravo 4 blade the Zero to plane time dropped to 7 seconds and the top speed was 79.8 mph GPS. All of the tested acceleration times of 20 to 40mph and 40 to 60 mph also dropped by over 1/2! Thats 4, yes 4 inches in pitch increase and now the boat hits this speed at 5000rpm not 5100rpm. Awesome horsepower and torque results that prove the 496 motor with Raylar upgrades will make the "HP525 blue motor" hard to justify! The motor was stock with just our kit. No ECM modifications! and with the stock Mercury exhaust with just our trick modification to the Mercury exhaust manifolds and our fuel pressure increase mod. Our BP103 kit consists of our "BigPower" aluminum cylinder heads with Cometic head gaskets, ARP head bolts and our special stainless steel roller rockers, our new "CoolGap" intake manifold and our new special profile camshaft. This is no fluke or smoke and mirrors. About two and one half years of serious research and development and a lot of investment has gone into making our parts and kits some of the best made and performing engine parts and systems in the industry. A lot of 496 owners have already ordered our parts and many are installing them now. A lot of new Raylar 496's will be going quicker this year all over the country. If anyone needs addtional information or wants to speak to the owner of this boat above, call me toll free M-F 8am to 5PM Pacific time @ (866) 496-8181 or by email at [email protected].
Ray @ Raylar

RDatTN

Ray:

appreciate the advice. Can you make any comments about reliability and durability and cost vs. other options?

Thanks

Russell

Raylar

As for reliability, remember, our kit consists of parts that are better engineered,manufactured , stronger and more precise than the factory parts they replace. Only time will ultimatly tell, but if our dyno, in the water and on the road testing for almost 1 1/2 years is any indicator , reliability and dependability will never be any kind of issue. Unlike supercharging, our kits do not stress the factory cast pistons and the cooler running aluminum heads and manifold actualy take heat loading off the motor and eliminate detonation while still using the same octane requirements for fuel. Power and efficiency do not have to stress engines and if properly applied can actually increase engine life. The current stock 496 marine engine tends to run to rich as sold and this will actually shorten ring life over the long run. The days of killer valve springs, out of tune carburators. lopey idles, reversion and short engine life are now being eliminated in many engines due to electronics and material and system improvements. The fresh water cooling of the 496 will be a huge factor in increased engine life due to even and constant operating temperatures. Todays drives should probably more of a reliability concern than the 496 and Raylar upgrades should be.

Just my opinion,
Ray @ Raylar

Nordicflame

iTrader: (4)

Jim,
Are you going to be testing any single or twin V hulls soon? That cat seems like it was right on the fence as far as lifting goes resulting the great gain. I would think a 100 hp increase would realistically net 6-7 mph.
Keep up the good work! Sounds great.
Dave

Hydrocruiser

If I had a 496 the first thing to go are the cast iron heads; I would leave the cam alone and probably change the intake manifold over to aluminum as well and then put a good set of headers on it and call it a day. Should be good for 75 HP. I don't feel comfortable putting a blower on the stock engine wheras I would be with a 502. I would shoot for durability and a modest increase in HP and torque.

just my usual .02