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Old 03-28-2009, 07:33 PM
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I am rebilding my 500HPs the only parts iam reuseing are my crank & rods (block&bair heads) I thought CMIs were a good replacement for Gils but after reading a thred about CMIs leacking I doint know what to do my bud get for exhost is $6500 PSthe boat is a 2000 35 FOUNTAIN (HELP)
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Old 03-28-2009, 07:35 PM
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Old 03-28-2009, 08:57 PM
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you can buy stainless marine gen 3s they come custom fit for your boat in 4 1/2'' which will be nice for your boat. I have a friend with cmi e tops and after 3 or 4yrs got a crack which was on the out side so it did not hurt the motors. I HAVE SEEN STAINLESS MARINE EXHAUST IN BOATS FOR 12YRS and still run. on the set up you need you can find them from 3000.00 to 3400.00 per motor complete,I know my engine builder can get them he is building me a 572 blower motor that we will use the 5'' gen 3s, DEAN GELLNER pm me if you need help. cmi makes a good unit, but my motor costs to much to use anything but STAINLESS MARINE.
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Old 03-28-2009, 09:21 PM
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The largest manufacturer of headers can be an easy target for complaints. There are countless CMI headers that are just fine. I for one have had them on my last four boats. So that is 8 sets leak free. Salt water can be hard on anything if not taken care of. Have you ever torn down a salt water engine? Unreal the damage you can find. The early 525's headers were a problem for Mercury that were spec'd by Mercury and built by CMI. That has since been remedied. Every Mercury racing engine use CMI headers for a reason. They are simply the best header on the market. Personally I think manifold style exhaust is rather plain without the bling that CMI's bring to the party.
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Old 03-29-2009, 01:24 AM
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The leaking header thread is probably the one specific to 525EFI headers. Those headers were spec'd by Merc and CMI makes them to the Merc specs.

The regular CMI's are pretty good and don't leak like the 525EFI headers. I would get some standard E Tops.
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Old 03-29-2009, 06:29 AM
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Unlike Airtime my engines (my motors start my engines) make to much HP not to run CMI's. I have removed Stainless Marine exhaust on customers boats and replaced them with CMI sport tubes and seen up to 4 MPH gains but what do I know I only work on them and he sells carpet or tennis shoes.
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Old 03-29-2009, 08:16 AM
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And I build the engines for AirTime....I have run CMi's for many years and the quality is bar none. The service they provide is outstanding and customer relations is superb!! Highly recommended!

Dean Gellner
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Old 03-29-2009, 08:45 AM
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I'm going into my 9th season with the same set of CMI E-Tops.

No issues at all but I do drain them down when the boat's not in use.
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Old 03-29-2009, 10:24 AM
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http://www.offshoreperformance.com/

I have bought 3 sets from Donnie her will discount them to you great service from them the last 5 years
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Old 03-29-2009, 10:52 PM
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Originally Posted by brian41
my engines (my motors start my engines)
Funny line. Everytime I hear or see someone calling an engine a motor I can still hear my Father telling me "electric motor, combustion engine". The thing is more and more people are using the word motor. Even my boat racer and mechanic friends say it. I bet 90% of people use the term motor when talking about an engine.

CMI's work great on engines and even on motors.

Last edited by Brad Zastrow; 03-30-2009 at 04:09 PM.
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