So putting back the stock thermostat might increase the risk of detonation (with the compression ratio of Raylar's heads, and the Stage 2 calibrations)? What else do you think can be done to substantially decrease the amount of soot. My brother-in law has the same boat but with a 540 and has no soot problems at all (he's running 750hp on the dyno). I often get a strong fuel smell from the exhaust when going through no-wake zones (stronger than my previous boat - a 502 carb).
Thanks
Bruce.

More Clean time
 

Guys:
As I have posted in the past, a lot of the black soot you are seeing on the back of the boats is from the fuel itself.
We've actually done some testing on the dyno and what we see is the black soot in the dyno headers after testing even when we have leaned the air fuels to a point of detonation and power loss. Most of this soot seems to be from the various fuel blends for the new lower emmisions fuels (HA!)
and when we used base (testing) fuels the soot disappeared.
On various hull designs the transoms especially extended transoms have a negative pressure area behind the boat at the transom that can pull the exhaust back to the boat and give it more time to deposit the soot on the transom.

My suggestion on the 496 is not to run 91 or higher octane unless you running a supercharger. On a stock or our Raylar 496's it is not needed and in fact its slower burn rate will create more unburned fuel in the exhaust and create more soot.

Just some info here to help explain the conditions for todays fuel soot!

Best Regards,
Ray @ Raylar

Ray, any info on the 2007 program yet. We had to pull the water pressure sensors and plug them off to keep the motors from going into gaurdian mode. As soon as the water pressure sensor hit 43 psi we would get an alarm an the motor would go into gaurdian and drop the rev limit down. Removing the sensor and leaving it plugged in and pluging the cooler has worked for now but it is a temporary fix.

Your water pressure should not be running that high in actuality. Check the system with another sensor or a mechanical guage and if the pressures are that high start checking your system for a restriction somewhere in the raw water system. I am surprised at those kind of pressures that the pressure relief valves have not been opening and dumping a lot of water in your bilge.

Best Regards,
Ray @ Raylar

No. The water pressure is not that high. When the key is on engine off the value for the water pressure is 28psi,then when you start the boat it goes to 32 psi. (So it is actually 4psi at idle) Since the new program you installed, the starting water pressure is 28psi! It is a programming issue that needs to be addressed.

I was having a major soot issue on my boat as well. The problem was there stock, then with a Raylar/Stage I and Raylar/Stage II. After explaining my problem to Ray and Dustin, I sent the PCM back for another tune (along with all my data). I now only run Sunoco 89 as well. A few runs later, the soot is gone! I don't know if was the tuning or the fuel I'm now running, but I'm not going to change either. :D

One more thing, I have a FASS 02 monitor @ the helm which reads both manifolds and I always know my AF.

I don't know who I should be thanking more - Bob, Dustin, Ray, BES or Plane Silly. Thanks guys! :D

Hey guys what I get a little soot too and was wondering what products are out there to remove the soot without removing the wax / shine and damaging the surface.
Is it at all possible to have a completely clean white transom after a day of operating??

I trailer my boat, so everytime I get home from the lake I wash the boat - doesn't remove the soot, though. I've found that Meguiar's Boat Wax takes the soot right off and leaves a coat of wax on the transom. If the soot is particularly bad I will use Meguiar's Mirror Glaze 45 Boat/RV Polish first (dissolves the soot right off), and then wax with Meguiar's Mirror Glaze 56 Boat/RV Pure Wax. The transom comes completely clean - no residue left behind at all. I have noticed that over time the gel coat has started to yellow a bit from the soot, not really noticeable.

Do you use the low temp thermostat that comes with the Stage 2 kit? What kind of engine temps do you run at? I have the Raylar 103 kit and Whipple Stage 2, and the transom soots up big time. I've been running 91/92 octane, but will try 89 instead. I'm wondering if the low temp thermostat is also adding to the soot problem (my engine runs 140-150 F). Did Whipple do a custom program on your PCM? Did they say what kind of changes they made to it?
Thanks
Bruce

I'm using the stock stat. I'm told you don't need the low temp stat and only need 89 gas with aluminum heads. Yes, Dustin did a custom program based on all the data I sent to him. I recorded the A/F, fuel pressure and manifold pressure @ 500 rpm increments. It's very difficult to get it tuned just right from 3,000 miles away, so it took a few times. I really don't know exactly what he did to it, but it works. :D As far as the gas goes, if you have Sunoco in your area, give their 89 a shot.