What is everyone's experieince in modifying the 500EFI?

What did you do?

Results: drivability, relaibility, HP gains, fuel requirements, speed gains (please include boat info)

Bill

Nobody's done anything, I can't believe it.

I know some people added Whipples. I don't think their is much you can do that will really give you noticable gains other than a whipple.

WILL

ASM has a monoplate throttle body and computer reprogram which adds 25HP for about $850. If you tear it down you can send the heads and manifold for porting and add ?25HP to someone like JimV.

Cobra marty

So will that be the same as a new merc 525??? I noticed a different throttle body on the new 525 25 hp for $850 So $34 per hp, may be good for 1.5mph gain

What is ASM website?? Thanks

Call Jim V. I think you will find that he can get you a lot more than 25 hp.

Who is Jim V and how can I get in touch with him?

I got an email from arizona speed and marine,,, they have a kit to make them a 525,,,,, just consisted of a throttle body and ecm reprogram

Boatinbill,
JimV is one of the top marine head porting gurus. He just finished the heads on my 540's and we just dyno tested one last week and it made 699hp @5700rpm and 704 ft# @4800rpm...that's almost unheard of with a single carbed, hydraulic cam, natuarlly aspirated, 9.5 cr in a 540" engine. His head work is top notch. 616-735-0800

Obnoxus,

could you send me a copy of the e-mail so I can check it out?

[email protected]

thanks