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Sport 280

07-27-2010 04:41 PM

500 EFI Headers

Looking to install CMIs on a stock Merc 500 EFI, will the computer need to be re-flashed?

Thanks

rmfriday

07-27-2010 10:14 PM

what cmi's are you installing? 500efi's came stock with cmi e-top headers

Sport 280

07-28-2010 08:01 PM

Quote:

Originally Posted by rmfriday (Post 3169464)

what cmi's are you installing? 500efi's came stock with cmi e-top headers

I think the headers are CMI Sweepers, with built-in mufflers in the tips. The mufflers are switchable.

Thanks

Griff

07-29-2010 12:51 AM

No, it will not need to be recalibrated.

Sport 280

07-30-2010 03:51 PM

Thanks for the information.

Elite Marine

07-30-2010 10:17 PM

Nope, just enjoy.

Irishtornado

07-30-2010 11:12 PM

Should be a Etop style header if they are factory. Off Topic how does your 280 run with 500efi's?

Sport 280

08-01-2010 01:24 PM

Quote:

Originally Posted by Irishtornado (Post 3171974)

Should be a Etop style header if they are factory. Off Topic how does your 280 run with 500efi's?

The 500EFI question was a for a friend.

I installed a pair of rebuilt 97, Lingenfelter 502s in my Baja this spring. Engines were originally 540 horse EFIs that John Lingenfelter developed with Mercury.

I installed dart intakes and hollies.

Still working on props, hope to see high 70s. If I get it right may see 80, but this thing chine walks really bad.

Thanks for the info on the headers for the 500 MEFI.

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