NEW 300XS upgrades

[DBR]

around 6300. I cant see exactly how this ecu works(Like an aftermarket one) but a hard limit hits in at 67 and adds fuel. You will know it when it happens.

[DBR]

we are working on inexpensive easy to install upgrades first...Level one..bolt ons that you can measure and do in the garage.

We also are very hard at working making Level 2 and 3 kits that will be very, very, fun. I am confident we will be releasing a 400 hp merc of some sort not too far off. The idea is to build reliable huge tq hot rods that run for years. Not minutes.

[DBR]

Dave, for a stock 300xs what method does Merc use for limiting the RPM and when does it start? Such as going richer or backing timing down. Mine seems very happy to about 6100 but does rev to 6250 but slower.


Have you considered doing mild port work without moving the power band up inorder to retain the torque/power?

Yes. Very much so but have to say again how good of job merc has done on both the x and xs.We are trying to keep hours of porting down along with cost. There is definatley areas that help when porting. These mercs are so much better than the other brands stock. Porting that is. WE are testing and learning like crazy. It also has been a great help to have been running the 3.3 johnson for so many years. These engines are all reacting very similar to each other. We are working on a 3.6 liter x/xs that will be designed to run the same rev range as stock but have more tq. We also have forged pistons and porting for the 3.2 liter that will have less tq than the 3.6 but a bunch more than the 3.2. or 3 liter.

[Euro Muscle]

ok, so what bolt ons do you have right now for the 2.5xs 05series eng ? Thx

[DBR]

nothing. All our time has been spent on the 300 first. Sorry it is next. It takes months of dyno time to dial in each engine. We have only one cell and are probably going to build another.

There is a good possibility that the cnc flywheel might bolt on but I honestly haven't checked yet. I am still learning all the differences between the years and models.

[Rayzor]

I'm not clear what you guys are talking about with the 'soft' vs 'hard' rev limiters. I've been running some short props on my 300XS while waiting for my taller ones and every time I get up to the rev limiter the engine goes into guardian mode after just a few seconds - and holds it in guardian mode for about ten seconds. It's nothing like the rev limiters in all the 2.5s and 3.0s I've had. At least with the stock ecu, you'd better prop your rig to not exceed 6,350 - or just not keep your foot in it on the big end.

[DBR]

that is correct...the soft is so small to feel it really doesn't do any thing to you hit the hard . In fact forget about the soft. depending on what tack and all the different electronics it hits very hard at 64 and tries to beat thru to 67 with short gearing...just stay out of there or bump up the limiter if you like short props or can pull a large one to 6500..6700

[Tom Foley]

we are working on inexpensive easy to install upgrades first...Level one..bolt ons that you can measure and do in the garage.

We also are very hard at working making Level 2 and 3 kits that will be very, very, fun. I am confident we will be releasing a 400 hp merc of some sort not too far off. The idea is to build reliable huge tq hot rods that run for years. Not minutes.

I can't wait for this ! Thanks !

[Double Rigged]

Dave, Looking forward to the 400hp motors! Thank you for the information. Keep up the good work.

[Chummy]

Very good reading, glad to see some improvements for these motors and looks forward to seeing what's next

[kostas74]

What about stock optis?(200,225hp)
Are you going to release any goods?
I think the stock optis have more potential for improvement than the XS's.
Is that right?

[Adam McKeon]

we are working on inexpensive easy to install upgrades first...Level one..bolt ons that you can measure and do in the garage.

We also are very hard at working making Level 2 and 3 kits that will be very, very, fun. I am confident we will be releasing a 400 hp merc of some sort not too far off. The idea is to build reliable huge tq hot rods that run for years. Not minutes.

Your efforts and hard work are not going unnoticed! Thanks again for all the wrench/keyboard time you have put into this and for being an active member here. Many of us are looking forward to the products your putting out.

[sterling2011]

Dave is there there a level 1 upgrade for the 2010 250 xs and should you expect the same type of gains out of a 250 xs

[spidee]

Dave are there any current mods for the 175 ProXS as bolt on or ecu flashing or flywheel mods if so please explain what you can offer me.

[eagle670]

Dave,

your new mods for cowl w/ 3 air intake, is'it any problem w/ water coming in , or does it have some kind of "water traps " ??

i follow all this " 300Xs upgrade " with high interrest, but my 300XS/2011 is under warranty for another 2 year, so i have to hold my horses