Can a 150 Optimax be upgraded to 200?

[codprawn]

Thats what I was getting at when I said they all shared the same 2.5lt block - quite old now but nothing wrong with that - some of the best engines are based on very old technology - to be honest there hasn't been much new with engines for the last 70 years!

Efficiency has improved due to modern engine management etc but variable valve timing - twin plugs - 4 valves per cylinder etc etc have been around for a hell of a long time!

[Justwin]

So do you reckon a XS 200 ECU would work on a 150? I think that there are probably more subltle differences ie port timing etc with that range of engines...

I know what you are saying about how long some of the technology has been around for - My dad has a 1926 Bentley 3 Litre that has four valves per cylinder and twin spark plugs/ dual ignition!

[codprawn]

Originally Posted by Justwin

So do you reckon a XS 200 ECU would work on a 150? I think that there are probably more subltle differences ie port timing etc with that range of engines...

I know what you are saying about how long some of the technology has been around for - My dad has a 1926 Bentley 3 Litre that has four valves per cylinder and twin spark plugs/ dual ignition!

Look at the link I posted earlier in the thread and email them - you never know!

As to the Bentley - WOW!!! It isn't only engines - the suspension on some of the best handling cars in the world was developed in 1910(de dion) it is probably tyres that have made the biggest advance and people don't give them a second though!

[Cookee]

Originally Posted by Justwin

So do you reckon a XS 200 ECU would work on a 150? I think that there are probably more subltle differences ie port timing etc with that range of engines...

I'm afraid you know about as much as I do about XS200's now!

[Justwin]

Model Shaft Cylinders Weight (lbs) Start method Gear shift Displacement
150XL 25” V-6 445* Electric F-N-R 2507cc

200XS 25” V-6 444* Electric F-N-R 2057cc


Looks like i'm foiled again...

http://www.defender.com/inflatables/...opti_salt.html

[Justwin]

Maybe not - looks like it could be a typo

Below is copied from the website...

"MISTAKES DO HAPPEN. Typographical, photographic, pricing, and editing errors in our catalog, flyers, advertising, and website are unintentional and we reserve the right to correct them."

200XS

Key Features

· Compact 60 degree vee, 2.5L (153 CID) powerhead delivers unmatched power, performance, durability and reliability.
· PCM 038 microprocessor provides maximum power and fuel economy.
. 2-star C.A.R.B rated.
· A unique two-stage direct-injection system atomizes fuel into small, uniform particles, resulting with a complete and instantaneous combustion.
· The 60-amp belt driven alternator is the most powerful in its class.
· Electronic multipoint lubrication system delivers precise amounts of oil where and when it's needed.
· The SmartCraft™ Engine Guardian system monitors engine functions for early indications of problems that could lead to engine damage.
· Race-derived exhaust chest and tuner for enhanced power.
· Torque Master and Sport Master gearcases feature a heavy-duty propshaft for enhanced durability.

[swginn]

Official Mercury figures here:

http://www.mercurymarine.com/200xs

and here:

http://www.mercurymarine.com/mercury...imax_saltwater

Although it probably is possible to simply change the ECU in the 150 to on from a 175 I'd say that as the 200XS is a racing engine and has a racing exhaust that would need to be changed too (the exhaust probably gives it some of the extra 25hp!)

I had looked at changing ECUs before but dismissed them because of the cost of the ECU and any work you need done on your Opti won't be covered under warranty as you'll have voided it!!

[codprawn]

Originally Posted by swginn

Official Mercury figures here:

http://www.mercurymarine.com/200xs

and here:

http://www.mercurymarine.com/mercury...imax_saltwater

Although it probably is possible to simply change the ECU in the 150 to on from a 175 I'd say that as the 200XS is a racing engine and has a racing exhaust that would need to be changed too (the exhaust probably gives it some of the extra 25hp!)

I had looked at changing ECUs before but dismissed them because of the cost of the ECU and any work you need done on your Opti won't be covered under warranty as you'll have voided it!!

Don't change the whole ECU - just the chip - and don't tell anyone!!! Any probs swap them back!

[Pete7]

Right, IMHO this is a non starter for several reasons not least Mercury have always been very adapt in the past to stopping people doing just this sort of thing. Secondly who is going to buy such an engine afterwards ? would you choose a standard 150 opti, or one thats 175 hp that was chipped by a geezer in the back of his garage. And if a new ECU is £1100 who is going to be brave enough to take one apart, cos I am certainly not taking mine apart. Its all very well for ppl to say just change the chip, thats not there ECU down the pan if it goes pear shaped. Watched my opti being set up with the Mercury lap top, your also going to need access to one of these and they aren't cheap.

If you want 200 hp, sell the current engine and buy another, they are available second hand, you just need to be quick to find them.

Pete