rich running 496/prop testing
 

Any one with 496ho in a 27? mine runs real rich
also anyone try any props. I'm running best of 69
@5100. usually 66-67. Have an xz drive, have large
shaft, need to buy props made for this drive?

How many hours on your motor, I recall a thread on their running rich for X number of hours then getting better. If you have low hours that also might be a factor on top speed. Fountains website says 71+ with the 496 so you are within 3 mph now.

Mercs EFI's run rich anyway. added an MSD boost to my 454 efi and it made a big difference on the transom soot

Can't help with props, but fountain usually does a pretty good job propping the boats at the factory, it's all about speed for Reggie you know. My 27 runs with the same prop it was tested at the factory with and did just a tad over what the spec sheet said.

prop
 

fountian; what prop are you running now???????? bill

The 496HO's run rich. I have 65 hours on mine and they still are leaving that pain in the arse soot to clean every time it comes out of the water. I do not use 92+ octane but it does not seem to matter. Merc says the new PCS555 (triple nickle) is going to do that because of the programing....

34 Vyper - you said you don't use 92+ octane! Why would you, the fuel requirements of for 87 aren't they? When I had a 502 I was told to burn nothing but 87 octane because it messes up the computer?

I may have mislead you... I never use 92+ only 87 octane. The computer will not be messed by 92 though.

340Vyper- you are using 89 octane fuel. There are no marinas around us w/ 87.

On my old '00 502MAG, I got more soot using 89 marina gas. When I brought gas cans full of 87 octane fuel, the soot was almost gone. When I put 89 back in, more soot.
Haven't tried this test on the 496HO. . . .yet.

Maybe that is why Reckless288 has no soot, he trailers to a gas station and buys 87?!?! :confused:

Thanks for the help..
I'm running a 26 bravo 4 blade at 5100, performance report
said 68 @ 5100. Which is pretty accurate. Have about 50 hours.
Have black soot on the swim platform and even on the back of
the hatch. Its tough to get it off the vinyl. Also have that air
sucking sound at low rpm's. Heard thats normal. Wrote to
crockett @ Hot Boat (june 2002) He said replace exhaust and flame arrestor. Any one try the k/n? sounds too good to be true
that any speed increase could result. He also said wrist pins too
weak for a blower on this motor. Warrenty is up in August, will
be looking to upgrade the motor or get a new boat, need more
power. Had 25 Advantage with HP carp, lot more punch for 45
additional hp.