Optimax 135

[Cybercoach]

Hello! I have a Mercury Optimax Saltwater 135 yearmodel 2006. Has anyone made the Ecu-modification to increase 135 Hp optimax to a 150/175 opti? How much does the operation cost? Do I have to make any other changes.
The gear ratio in 135 is 2.00:1 and Opti 150 has 1.87:1
Thank you already!

[RIB BOI]

it not so easy mate. we looked in to conveting 5.7 v8 gsi in to gsx with have more hp for a man who is lookin in to havein a new boat built for him as his 8.1 lt dose not go fast anuf and dose not burn anuf fuel so hes havine two 5.7 and wanted as much hp out of them and we looked in to doin it u have to have new pistons, cam shaft, ecu, the head re word the list whent on and on so on a big outboard there is no point just pay the cash and get a biger one.

RIBBOI

[Cybercoach]

Thank you for your opinion. Is here in the forum anyone how has actually made the modification or really knows somebody who has made it? I noticed that the ecu for 150 optimax costs in ebay 400 euros and in mercury dealer like 3000 e euros in Finland

[CJL]

It can't be done, mainly for financial reasons.

Have a look here Scream and Fly Linky and you may be able to squeeze some more out of it with a programable ECU.

Beware though, extra performance will come at the cost of fuel economy and reduced engine life (plus your warranty will be void!)

Chris