NEW 300XS upgrades

**strokerdean** · 09-17-2011, 06:54 PM

Thanks for the reply, I ran the boat today (91) with my fishin partener following for a short distance and no water is being sucked into the cowl. He said there is nothing close to the back of the motor. That being said I have added a water outlet tube (3 1/2" long) where the water exits the motor. I saw something similar on S & F motors for sale a long time ago. It does direct the water down and away from the motor. Before adding this, the motor used to get wet.

**Thycon** · 09-21-2011, 07:01 AM

Dave
I race a twin outboard offshore cat with 300xs s and have a huge problem with salt spray being sucked in. Can I run the carbon air intakes without changing the ECU. If so how much are they each
Cheers
Antony

**Revolution141** · 09-21-2011, 08:45 PM

Anthony
My name is Kurt Hamilton. I live in Townsville. I have always watched you guys in the outboard cat classes and cringed at the amount of spray hovering off the backs of your boats and being ingested by your motors. I cant help but think the moulded fibreglass shrowds (not sure of the correct terminology, sorry) would be a huge factor in your problem as they create a negative pressure zone at the front of the engines, pulling salty mist in to envelop the cowls. Have you tried removing them to see if this problem improves? I cant help but think DBR's different intakes would not cure your problem whilst those shrowds are there. Not to say you would have no water ingestion problems without them however i believe they are the major source of your issues.
Love watching you guys when your here in townsville by the way.

**powerabout** · 09-21-2011, 09:07 PM

you need sealed cowls with pipe coming forward into the boat
All cats drag a fog behind them which eventually kills the engines

**Revolution141** · 09-22-2011, 12:26 AM

Not bad idea. Then draw air through an ice box. Would have to seal intake to top of throttle body though to separate hot air in cowl from intake charge. Would be easy to seal cowl. Just expanda foam inside of cowl where air comes through original intake

**dentguy** · 09-22-2011, 02:19 AM

Can't forget about the air pump intake as well... If these engines are getting as wet as everyone is saying, aren't the air pumps sucking water and injecting it directly into the cylinders?

**Revolution141** · 09-22-2011, 03:05 AM

True dentguy. You could run new intake for compressor to boat as well. would take some playing around so you can just pull cowl off and put back on and know everything is lining up and sealed but it can be done. Dave have you noticed marked differences in power when intake temps are lower. I know an old trick was to stick a resistor in intake temp sensor to trick engine into thinking it was drawing colder air? I have noticed if i get on it before engine is at full temp (around 48deg C)i gain 2 mph for a short period of time so sounds like there is some method in the madness!

**eagle670** · 09-27-2011, 02:57 AM

Dave , any more news or pict to feed us with

Peter

**alli-runner** · 10-18-2011, 05:44 PM

Any updates?

**Teddy G** · 10-21-2011, 05:40 AM

Spoke with Dave yesterday about 300XS upgrades.
300XS with the Level one kit, ECU upgrade, light flywheel, and add on cowl ram air carbon intake, make the same power as a stock 300X- @330 hp or so.
Uses 5 gph less fuel throughout much of the rpm range.
300X style cowl being tested next week.

**suk35** · 11-06-2011, 09:14 PM

Any new updates?

**Mr. Demeanor** · 11-06-2011, 10:29 PM

How about a simple oiled filter similar to a K&N siliconed to the inside of the cowl over the intake vent? They shed water but let air through. Dirt bikes, 4 wheelers, etc all use them to keep water out.