raeburn,
Is your motor NA or blown?? I dont see a reference to it. I have a data log from my 565" NA motor if you are interested.. I could email it to you..
Dick

It's a NA 496HO, with Raylar 103 heads, intake, cam. Also running Whipple's Stage 2 ECM with CMI Sport tube headers. If you don't mind sending me your data log I would appreciate it. I will PM you my email address.
Thanks!

The Whipple Stage 2 ECU conversion is marketed on the web site for upgrading a stock 496 with 43 psi fuel pressure. I assume that Dustin was aware that your engine was not a stock 496 but a Raylar BCK103 upgraded motor that runs at 50 psi fule pressure?

No, I don't think Dustin knew it was going to be running 50lbs fuel pressure instead of 43. I will definatley bring it up with him. Thanks for the input

If you look at the Raylar web site the posted AFR numbers from the dyno tests are a lot leaner. My personal targets 13.5-12.5 idle/13.0-12.5 cruise/12.8-12.3 WOT. Keep in mind that each cylinder has a different AFR/rpm and AFR from a bank of 4 cylinders is an average so unless you record all eight individual cylinder AFR's you hedge toward the lower side. An example of a work in progress is attached.

Dustin at Whipple has been a great help. After sending him my numbers, he suggested that I lower my fuel pressure by 5lbs (50 down to 45). I'm a little cautious with this engine so I went down 3lbs - it brought my AF up from 12 to 12.3 avg. 12.5 is my target with the aluminum heads so I'm going to go another 2lbs lower and see what happens.
I'm still very rich at idle and low rpms (12.0), so I will send the PCM to Dustin at the end of summer to clean that up. I have picked up about 100 rpms already, so there is definately a few HP being left behind by being too rich. So far best mph is 73.5. I sent my labbed 28p bravo to Bblades to get tweaked a bit more - I would really like to see 75 on gps this year!
I picked up Hardin Marine's new 496 flame arrestor - l don't know if it flows better than the K&N, but it sure looks great!
Will update after running with lower fuel psi.

Update? what was your final a/f ratio?

I dropped the fuel pressure to 46lbs and it raised my air/fuel ratio a little more. I am seeing wot a/f of around 12.5 and mid-range (3000-4000) a/f of about 13.5. This seems about right. The idle/low rpm a/f is still too fat (12.5) so I will send the PCM out in the fall to get that leaned up a bit. The transom soot is still just as bad though. I spoke to Ray @ Raylar and he is insists I should only be running 87-89 octane (I'm too chicken to go below 91 because I heard the Whipple Stage 2 calibrations shuts off the knock sensor/timing retard program in the PCM). He said they found 12.8 to be the best a/f ratio, so I might drop another pound or two and see what happens.
BBlades got my prop back to me in time for the run - as promised (Thank you Brett!) I picked up another 150 rpms and almost made 75 (74.5 with 3/4 tank & 2 people). Boat ran great!!

I thought Ray told me WOT A/F ratio was supposed to be around 13.5?

Isnt 12.5 still kind of rich for WOT?

FYI - test your stock flame arrestor - mine performed 1 MPH better than K&N and the Hardin.

I was told 12.8 at wot and around 13.5 mid-range cruise, Dustin at Whipple told me 12.5, I think he's being cautious.
My main concern now is cleaning up the idle/low rpm's. That is where most of my transom soot comes from. I notice a huge difference when I run the exhaust through the leg at low rpm's compared with running it straight out.

My stock flame arrestor is long gone. The Hardin Marine arrestor seems pretty good, I took out probably three-quarters of the stainless mesh (left two layers in) - I also took a grinder to the inside of the little velocity stack on the arrestor and smoothed out all the edges.