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-   -   Modifying Mercury Racing 450R to make more power? (https://www.offshoreonly.com/forums/general-boating-discussion/377383-modifying-mercury-racing-450r-make-more-power.html)

Strip Poker 388 10-14-2022 09:56 AM

Modifying Mercury Racing 450R to make more power?
 
Can a Merc 450R outboard be turned up to make more power? Reprogram and turn boost up etc. Like what Whipple and others do to the supercharged Merc inboard motors, 700's 1075's I know it would void warranty & maybe shorten life. But, What you think?

Sydwayz 10-14-2022 10:03 AM

The problem is the the lower of that motor. Even B1 XR lowers have trouble holding together at 500+ CSHP when being overly beaten on by shock loading.
And Mercury Racing already has issues with propshafts on this motor, which they believe they have solved with the latest batch.
You will see the 600HP V12 outboard is only for big boats that really don't leave the water, shock loading the drive on re-entry.

That's why you see folks just bolting on more 450s instead of them being bumped up in power.


Old hoax:
https://cimg6.ibsrv.net/gimg/www.off...c45807e769.png

PremierPOWER 10-14-2022 10:13 AM

I doubt it, the EPA and Mercury locked down the tuning on them. Whipple use to offer it for the Verado 300/350/400 but had to stop.

boostbros 10-14-2022 08:07 PM

come on someone please old school one of the 450s put some straight pipes and carbs on it for us old schoolers were not all dead yet! stock these motors sound terrible let her sing, there ought to be quite a few salvage ones after the hurricane with salted and fried computers lets have at it! an old school 450 with zoomies for all of us engine geeks that grew up on merc 2.4s 2.5s screaming till they puked ah the good old days!

compedgemarine 10-14-2022 08:19 PM

not a 450 but it is a mercury and it does have zoomies

https://cimg4.ibsrv.net/gimg/www.off...227a61fb4a.jpg

Lake rat Skater 10-15-2022 06:40 AM

A week or so ago there was some pictures floating around of an inline 6 verado with a Motec ecu. I think that is the most realistic / best chance of a solution to add power to the 450. As noted the lower is the weak link and mother mercury has put an end to ecu reflashing. The stand alone motec ecu would provide a lot of options and I would think another 50 hp could be gained just in tuning and setting them up for 93 octane only.

Interceptor 10-15-2022 12:06 PM


Originally Posted by boostbros (Post 4848218)
come on someone please old school one of the 450s put some straight pipes and carbs on it for us old schoolers were not all dead yet! stock these motors sound terrible let her sing, there ought to be quite a few salvage ones after the hurricane with salted and fried computers lets have at it! an old school 450 with zoomies for all of us engine geeks that grew up on merc 2.4s 2.5s screaming till they puked ah the good old days!

Yup, did that. Now I'm deaf.

hogie roll 10-15-2022 12:47 PM


Originally Posted by Lake rat Skater (Post 4848231)
A week or so ago there was some pictures floating around of an inline 6 verado with a Motec ecu. I think that is the most realistic / best chance of a solution to add power to the 450. As noted the lower is the weak link and mother mercury has put an end to ecu reflashing. The stand alone motec ecu would provide a lot of options and I would think another 50 hp could be gained just in tuning and setting them up for 93 octane only.

I agree, aftermarket ECU.

An e85 tune up with a tiny pulley would be sick

Strip Poker 388 10-17-2022 11:42 PM

Didnt know Merc had tightened up, Kinda like the 1075's turned up running with the supercats in the day:rolleyes:

Rob

Menage_Aqua 10-18-2022 08:54 PM


Originally Posted by PremierPOWER (Post 4848176)
I doubt it, the EPA and Mercury locked down the tuning on them. Whipple use to offer it for the Verado 300/350/400 but had to stop.

https://www.motec.com.au/filedownloa...jpg?docid=6231

Looks like the Aussies found the master key for the lock Mother Merc and the EPA tried to apply.


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