Can a 150 Optimax be upgraded to 200?

[Justwin]

I was just wondering.... seeing as the 150 and 175 / 200 etc optimax's use the same block, does anyone know if a 150 can be upgraded horsepower wise to say 200? Possibly an ECU change or something? (Mariner in this case)

Any information would be gladly recieved as it has to be cheaper than buying a new engine...

Too much is never enough!

[TIM]

I dont think this is possible.......

As far as i am aware, the intake ports and exhaust port are different heights in the block, ie for 150-175-200 and to up the HP you would have to change this........ I dont think its a matter of rechiping or reprograming the fuel injection......

I am only 60% certain of this though ....

[Daniel]

I must be your 40% then Tim... I am 99% sure it's just an ECU swap that's needed. I think they are nearly £3k though.

FYI as far as i remember it's the 135/150/175 that are the same, 2.5li v6 the bigger engines are 3litre and no amount of electronics can change that.

[Justwin]

hmmm, 3K for 25 horse - barely worth it I suppose... I would suspect that it is just electronic and possibly the exhaust system too, at least I'm told that that was the case on the older Yams. I can't imagine the the cylinder casting would be any different for production cost reasons.

[DM]

Originally Posted by Daniel

I am 99% sure it's just an ECU swap that's needed

I must be your 1% Daniel. I'm 99.9% sure that the bore/stroke are different between the 150 and 200. I am 100% sure that the gear ratios are different.

I am only 25% sure what month it is.

DM

[codprawn]

200hp is different but the 175hp is the same - prob is just an ecu swap - many modern engine makers do this - especially on turbo diesels.

3k for an ECU is just daft - maybe someone does a reprog chip or else you could borrow a chip and read out the codes.

http://www.brucatosvs.com/

These people actually do upgraded adjustable ecu but not shure if for optimax yet!

[TIM]

Well if its just ECU then go for it ......

I am sure you can get someone in the states who has done this before... you could proably fine it on the web.... with fichts we can reprogram form a laptop , and can get the sofware from the web

The Piont I made about the ports.... the block and bore stroke are all the same ... but the difference is that the hieght of the intake and exit port a crutal in a 2 stroke ... 1mm makes a huge differance in the final HP of a engine........

So they might have the same blocks etc but suttle differences , are the key . this is why we are stuck with 75 instead of 115hp

[codprawn]

You could well be right TIM - until we actually see some blueprints or someone takes them apart we will never know!

[codprawn]

Having said that the optimax is based on the old 2.5 block - various different sleeves are available which contain the ports - on the old sleeves they were the same for the 150 - 175 and 200hp models.

[daviesd]

I think the 135 / 150 / 175 all use the 2.5l block, but the 200 / 225 / 250 all use the 3l block.

[Rogue Wave]

have a sniff around some of the American sites scream and fly or OSO (offshore only) the market is a bit more sophisticated out there and the chips may be cheaper.

[Daniel]

Originally Posted by davidmanning

I must be your 1% Daniel. I'm 99.9% sure that the bore/stroke are different between the 150 and 200. I am 100% sure that the gear ratios are different.

I am only 25% sure what month it is.

DM

Completly different engines are the 150 and 200 so yes you are right.

The 150 and 175 share the same gearbox. All the part numbers are identical, except stickers and ECU, hence i'm so sure - i have done my homework on this one. I have a plan up my sleve to prove this but wait and see...

[Rogue Wave]

Mr Manning, Rumour has it my chip in my Happymax has been sorted. It's not me but I am told that it was upgraded when Nokia owned it. I was told this by the guys from Lee Faiweather's. As you presently are kindly rebuilding my Happymax have a look around the ECU and see if it's been interfered with (if you want to that is).

Daniel, how are you ......you don't call , you don't write when are you and Tappy coming down next.

[Daniel]

I'm alive old boy, manic with work that's all. Last time we spoke i thought you were visiting me. Pleased to hear engines and boats are starting to get it together for you and i'm planning an alderney dash in september i think so see you then (are you coming?)

[DM]

Originally Posted by Rogue Wave

have a look around the ECU and see if it's been interfered with

I'd love to do this but it was mistakenly sold at a car boot sale. oops.

The chip may well have been remapped when it was owned by Nokia. This would explain why the smartcraft gauge occasionally said 'you have 3 new messages'

Mariner 200 optimax. Mariner 150 optimax

Bore/stroke 3.63 x 300 3.50 x 2.65
cc 3207 2507
Gear ratio 1.75-1 1.87-1
Weight 497lbs 431lbs

DM

[Daniel]

Originally Posted by davidmanning

Bore/stroke 3.63 x 300 3.50 x 2.65

??

[DM]

Originally Posted by Daniel

??

Delete the bloody full stops and add some spaces . The information is there. You just have to look for it .

D M . .

[Justwin]

Thanks for all your replies, it was a while since I looked at the specs on the Merc/Mariner website, and after looking again - obviously a 150 is of a smaller displacement than a 200 so that upgrade would be tricky to say the least! As for the 175 option, looks/sounds promising....

[CJL]

Originally Posted by daviesd

I think the 135 / 150 / 175 all use the 2.5l block, but the 200 / 225 / 250 all use the 3l block.

Daviesd is correct. I`ve had a 150 Opti and I`m now on a 135. They are both based on the 2500cc V6 block. I asked the question on how much it would cost to up-rate the engine to 150/175 and I was told by the mechanic that the ECU would need to be replaced at a cost of around £1100. Not really worth it in my opinion. I`d play with the props and the boat set up first.

Plus there is the warranty issues!
Chris

[Cookee]

Just to throw a spanner in the works the XS 200 which is also an Optimax is a 200 hp 2.5 litre engine!