probably but it may not be as simple as that.

injectors could be different but are more than likely the same.

the 115 mercs on my boat are the same as the 80 and 100 engines but you cant put the ecu from the 115 on to the other engines to make it a 115.

 

And why can't you swap them??

 

You will lose your warranty as well Stu, and have you seen the price of Suzy ecu's and injectors, you may want to check the gear ratios too?

 

Also the cams may be different, don't forget they are twin cam motors too?

Gear ratios are the same by the way.

 

By the time you have fitted the 90 ECU plus any other parts required it will have cost you as much or more than the price difference between a 70 & 90.
Manufacturers do this to stop people just buying the lower hp engine in a model range & fitting the higher hp ECU.
Also they generally want the old ECU off you (Evinrude certainly do) so to get a 90hp ECU you would have to give them a 90hp ECU.
I looked into this quite a bit for a friend with a 75hp ETEC who wanted to uprate it to 90HP.

 

As Headlight says, the manufacturers are incredibly protective of the upgrades of modern engines and make the higher rated ECU's incredibly expensive and monitor the sale of them very carefully to stop people buying the lower rated engines - look at Evinrude for example - the 200 is the same engine as their 300 - they're not going to make that extra 100hp accessible to anyone for less than the price difference between the two ratings and would come down very hard on a dealer that tried to do it too.

 

Exactly Clinker.
When I looked into it for friend who wanted to uprate the power of his ETEC 75 to that of an ETEC 90 the ECU alone cost exactly the same as the price difference between the price of a new 75 & new 90, plus they wanted the "old" 90 ECU as they reckoned they needed to programme certain information from it into the new ECU ?
I don"t know whether this was true or just to prove that you were really replacing the ECU on a 90 & not just uprating a 75.
They also wanted various serial numbers off the existing 90hp motor.
Obviously we had none of the above as the original motor was in fact a 75.
Things are not as easy now as it was back in the day with carbed 2 stroke outboards where often a jet change or carb change would increase the power of an outboard to that of a higher one in the same model range.

 

Probably the cheapest, and certainly the simplest way to do it would be to part ex your 70 against the cost of a new (or even a used) 90.

 

Also worth checking that you're getting the best from the current engine with the optimum mounting height and best prop.

 

If you check the part numbers on here http://www.boats.net/parts/search/Suzuki/Outboard/2011 and Later/parts.html you see that the camshafts are different.

 

There are very simple & cheap ways to modify ECU"s to produce more power.
You can buy plug & play ones for cars for not much more than £50.
Basically they have a resistor in them that when plugged in to the ECU loom fools the ECU into thinking that the O2 it is receiving is colder & therefore denser than it actually is.
As a result the ECU injects more fuel resulting in more power.
I have no doubt that this could be done cheaply for an outboard ECU by someone who knew what they were doing.
The problem is though that this method of increasing power can have side effects such as rough idling, difficult starting, bore wash & potentially engine damage as basically all you are doing is over fuelling right across the rev range.
The proper way is to have the ECU properly re-mapped, with the aid of a rolling road, in other words it"s entire programme over written with a new programme.
This is what fitting a differently power rated ECU does as it has a different programme to the lower powered one.
I can buy a plug & play ECU power chip for my car that for £60 will increase it"s power from 150bhp to 190 bhp but the remap/rolling road session to do this properly & safely is about £600.

 

I'm glad I've opened a can up for everyone to get there teeth into!!

 

Personally don't eat worms......but each to their own I suppose :veryconfused:

 

So you would need to most likely change the sensors, injectors, ecu, re-mapped....

Yes you may increase the power but the key bit of information is the torque speed curve of the motor. Power is Torque x Speed so in changing the power in the shaft the torque goes up and then bearings get damaged etc. There is a reason why manufacturers are very careful with ECUs.... it's not just cost, it reliability, emissions etc too

 

There are very simple & cheap ways to modify ECU"s to produce more power.
You can buy plug & play ones for cars for not much more than £50.
Basically they have a resistor in them that when plugged in to the ECU loom fools the ECU into thinking that the O2 it is receiving is colder & therefore denser than it actually is.
As a result the ECU injects more fuel resulting in more power.
I have no doubt that this could be done cheaply for an outboard ECU by someone who knew what they were doing.
The problem is though that this method of increasing power can have side effects such as rough idling, difficult starting, bore wash & potentially engine damage as basically all you are doing is over fuelling right across the rev range.
The proper way is to have the ECU properly re-mapped, with the aid of a rolling road, in other words it"s entire programme over written with a new programme.
This is what fitting a differently power rated ECU does as it has a different programme to the lower powered one.
I can buy a plug & play ECU power chip for my car that for £60 will increase it"s power from 150bhp to 190 bhp but the remap/rolling road session to do this properly & safely is about £600.

I am guessing you have a turbo or supercharged engine not a naturally aspirated petrol. The process you describe won't work for a petrol. You have a certain air flow into the engine and, to prevent damage, a fairly small range of fuelling that will work with that air flow. You can get small gains with minor adjustments to mixture and timing but for significant gains you need to get more air in.

 

Ok yes turbo.

 

Come on get your Wallet out! buy bigger engine/boat

 

Hi theres a boat in our club thats got a 70 suzuki 4stroke thats blown a head gaskit hes looking to sell as spears.