GTI 130 : My V-TECH experience

[gti 130 wow]

I just had my first day on the water after installing the V-TECH firmware on my boat .
The GTI-130 Rotex engine is purposely detuned by Sea Doo for marketing reasons .
The engine from Sea doo makes 96kw or 131 hp at 7300 rpms . The Rotex engine with proper firmware installed puts out 106kw or 144 hp at 7500 rpm .These figures come from the Rotex web site and its in the 2015 Sea Doo GTI users manual . I got the results I expected and and happy with it .



Before : 56mph@ 7350rpm
After V-TECH mod 59 @ 7550
conditions : choppy water , 45 degree tempt.

Their is more to the story then just 3 mph .
When cornering at 50mph on my favorite twisty route for example ,the stock motor does not have sufficient reserve power at full throttle to keep the speed from dropping . The V-TECH does which to me is a big deal .

One important measure of the performance of an engine is the width of its power band or the range of rpms that it can put out large amount of power. The spread between max torque and max power indicates how good the engine performs . On the stock GTI-130 engine its 6000 to 7300= 1300 rpm . On the V-TECH tuned engine its 6000 to 7500 rpm or 1500 rpms . That broader power band is what helps keep the speed up in cornering .

I am happy to see that the touring and eco mode still work fine.
I don't understand why they changed the rev limiter to 8600 rpm because the only time it hits that peak is in the drive way so I plan to send off a e-mail about that .

 

[gti 130 wow]

Here is the link to the Rotex web site showing what the engine that's not software detuned will do .

https://www.rotax.com/en/products/rotax-powertrains/details/rotax-1503-na-4-tec.html

 

[gti 130 wow]

GTI 130 v-tech tune week two

Well so far things have gone pretty well.
I am still not able to reset the maintenance reminder , have read on some previous post that others have had the same problem , and hopefully they will send me a update that will remedy the situation.

Here is what I discovered this week.

1: Click on the link below to see my little race coarse that starts at the exit from the boat ramp and ends on the North Landing river in Va Beach . about a 5 min run which is just right for me.

https://www.google.com/maps/@36.6917007,-76.0405763,17z

The engine is now doing a much better job in the corners keeping up the rpms and speed. The engine is now defiantly running on the cam all all the time which makes things more fun . Rpms stay above 7300 rpms in the corners and hold the speed above 50 mph at all times. To put that into perspective , the stock tune typically runs max around 7280 at 55 mph .

2: Air temperature seems to be a bigger factor then before. On the stock tune the boat pretty much runs 55 at about 7280 rpms no matter what the air tempts our pressure is . With the new unrestricted tune , the ecu provide the right mix of fuel no matter how fast the engine runs up to 8300 rpms . So last week at 45 degrees the boat ran 59 at 7550 rpms . This week at nearly 80 degrees out side the boat ran 57 at 7360 rpms . So air density is now factor after a tune .If you get a tune , get to the dock super early for max performance .

3: Fuel

Today I used about 25 gallons of fuel which was about 5 gallons more the what I normally use .
The further away from the 6000 rpm torque peak , the more wasteful the engine will be so I am paying a price for those extra 250 or so rpms .

4: Sport mode : I am sure glad they did not do what some wanted and have it start in the sport mode because it would be like having a launch button on a rocket and who the heck wants that when your at the boat ramp. Instead they got rid of the message that comes on that you must read before pushing the button again . Now you just push the button twice quickly and your ready for lift off .

5: oil consumption : none/ still at 1/2 where I put it when I changed the oil
I did not get the tune until the motor had about 55 hrs on the engine so in its detuned form it had a easy go of it at the start which can help with the heath of the engine in the long run.

6: On the Rotex web site with a proper tune max hp should be at 7500 rpm so the boat may be a little over propped in the summer and under propped in the winter or just about right but Know way to know for sure because V-tech does not publish P =f (rpm) data which is to bad.


As far as speed is concerned, what I have now is a ecu with a proper tune that gives me the top speed performance of the GTI -155 . But other factors like mid rpm torque and throttle response would have to be evaluated by someone who has driven a GTI-155 boat . I don't think I would recommend such a tune for the better boat . Like the 60 hp spark , I am getting a big boost in performance as a result the fact that the stock ecu tune purposely limits performance by screwing up its tune above about about 7300 rpm right when the engine is primed to do its best not necessarily due to some kind of clever tuning. .

 

[gti 130 wow]

Speed =f( tempt) so far

45 degrees: 59@7550 rpms
75 degrees: 58@7400 rpms
80 degrees: 57@7380 rpms

 

[gti 130 wow]

12/26/2015 on the coarse and fuel Economy and range

My coarse at 67 degrees temperature :

https://www.google.com/maps/@36.6917007,-76.0405763,17z


speed range : 50@7350 to 58@7480 (note : I have less the 100hrs experience on a pwc )
Rpms running in a 130 rpm range which is much better then stock and adds to the fun . The stock rpm range was about 6900 to 7280 or a range 380 rpms which shows the difference . This engine now really fights like hell to keep the speed up in turns .

 

[gti 130 wow]

Fuel consumption

All day more then 50 % in :

ecno mode : 15@20 gallons closer to 15
sport mode : 25@30 gallons closer to 30

Before the tune , I never had used more then 20 gallons so that gives a rough idea of how much the performance cost + High test fuel that with a 10.6 cr engine some would argue you should be using anyway. If you spend all day in the engines new 7300 to 7550 rev range , you will burn a lot more gas then before .

 

[JoeZ]

Some nice numbers and information. We haven't done extensive testing on the 130 with a vtech tune, but this thorough information really shows the differences. I may have missed it, but where are you riding for these numbers? River?

 

[gti 130 wow]

Some nice numbers and information. We haven't done extensive testing on the 130 with a vtech tune, but this thorough information really shows the differences. I may have missed it, but where are you riding for these numbers? River?

I boat on the west neck creek and intercoastal waterway in Va Beach .

The west neck creek is 2 miles of curves with no blind spots .
Just check out the link .



https://www.google.com/maps/@36.6917007,-76.0405763,17z


Buying this tune was a leap of faith . I found one on you tube video with a guy claiming almost 100km/ hr or 61 mph but sad to say that was not so.I thought I would do a service by posting my results .I read about people uping the performance of their sc boats boats but sad to say its overall cost is to high for many including someone like me who wants to use it every weekend . So with my post , you can now make a informed decision on whether it's worth $900 for you. My only complaint is that the maintenance required reset is not on the menu for my tuner and have not got a response so far .

 

[JoeZ]

Nice riding area. Modding is definitely expensive, and addictive!

If they don't get you sorted at V-Tech, we'll help you out. We are an authorized V-Tech dealer.

 

[gti 130 wow]

Nice riding area. Modding is definitely expensive, and addictive!

If they don't get you sorted at V-Tech, we'll help you out. We are an authorized V-Tech dealer.

Mike at V Tech finial got to me .
A software update now has the maintenance reset and error history clear working fine

So I now have :

1: A meaningful increase in hp
2: Much improved mid rpm power band by employing a more aggressive engine timing
3:Two quick clicks and I am in the sport mode
4:The ability to reset the maintenance reminder and read and reset error codes

 

[hfgreg]

Great news thanks for the update. I am sure others will find this thread helpful when it comes to the GTI.

 

[delonnelj]

Nice riding area. Modding is definitely expensive, and addictive!

If they don't get you sorted at V-Tech, we'll help you out. We are an authorized V-Tech dealer.

Mike at V Tech finial got to me .
A software update now has the maintenance reset and error history clear working fine

So I now have :

1: A meaningful increase in hp
2: Much improved mid rpm power band by employing a more aggressive engine timing
3:Two quick clicks and I am in the sport mode
4:The ability to reset the maintenance reminder and read and reset error codes

Thanks. I'm debating if I should tune as well.

 

[gti 130 wow]

Long term update ;
My GTI 130 Sea Doo purchased in the fall of 2015 and received a tune in the summer of 2016 now has an in creditable "492" hours on it . During that time , the only problem I had was a in warranty bearing failure in the jet pump which as you know could have possibility been the fault of something being sucked in but no way to tell .Oil consumption is nil so long as I don't do things to cause the revs to go over about 7500 rpm's . This makes my Sea doo the best mechanical purchase ever for me .I ride with people who have SC motors and I find although they can go at speeds as high as 80 mph , doing so is rather nerve racking and quickly drains their gas tank . Their typical high speed cursing speed is in the 55 to 60 mph range that makes my V Tech tune spot on .I here of problems they experience with their high strung engines including one recently that had to have his sc Yamaha engine over hauled do to some failure . The day the fail occurred , I had to give him a tow back to the dock in Norfolk on my trusty GTI 130 . For me I have a great balance between performance , reliability and safety when I have yet to read of someone hurt going 60 mph or less and falling off although I am sure its possible .