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496 HO - Remove Turbulator and Lost Speed?

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Old 08-19-2009, 06:46 PM
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Nice find. That looks like a used truck pull out to me. Without ascessories, I still think you would be hard pressed to put that motor or any motor together the same as a complete 496 HO for less than 10k.

Also disagree that Blue motors are easily found under 10k. If you want something that doesnt need to be freshened or hasn't been damaged that would be a hard find. Here is a great example: http://www.500efi.com/

Last edited by CheckedOut; 08-19-2009 at 06:59 PM.
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Old 08-19-2009, 06:52 PM
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Originally Posted by jordy View Post
You answered your own question. For the few mph gains you'd get by changing exhaust, etc. with the 496's you'd be better off to save your pennies and hundies and go with some blue power. The 496 is a great engine if you leave it alone and let it run like it was designed to run. I know it's tempting to start tweaking on them in the never ending quest for more speed and power, but then reliability starts being sacrificed... which is more important?
Well actually my question was about the turbulators. I hear ya though. I understand what I call the 496 dillema very well and will eventually goto different power. For now however, I am looking at other mods that are not silly money for these stock black motors. Case in point, There was a dyno proven 8hp to be gained on by removing the turbulators but I am interested in what possible side effects (outside of the obvious potential reversion/ moisture burn off) that could be caused by it and if it's possible to lose speed.

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Old 08-19-2009, 07:48 PM
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Quote:
Originally Posted by CheckedOut View Post
Well actually my question was about the turbulators. I hear ya though. I understand what I call the 496 dillema very well and will eventually goto different power. For now however, I am looking at other mods that are not silly money for these stock black motors. Case in point, There was a dyno proven 8hp to be gained on by removing the turbulators but I am interested in what possible side effects (outside of the obvious potential reversion/ moisture burn off) that could be caused by it and if it's possible to lose speed.
To me, for 8 hp, which will likely go unnoticed, I wouldn't want to risk reversion/moisture issues. Merc has been playing with a bigger budget than most shops out there combined for a very long time, which leads me to believe that if something is there, it's probably for good reason.

Now I know that you can get more power out of them, but in the long run I've seen and read of more problems on engines that people tweaked on and tried to get every possible bit of power out of, than in the ones that left them alone, did the scheduled maintenance, and ran a couple mph slower.
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Old 08-19-2009, 07:51 PM
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I would think that there is someone that has had these things off for a long period of time that would chime in....
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Old 08-19-2009, 09:55 PM
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I've put about 50 hours on my ho's without turbulators. They sound better, and I certianly didn't loose power or speed. Why would removing an exhaust restriction reduce speed? A large part of the gains the aftermarket exhaust is claiming is due to not having the turbulators. They reduce diameter about an inch.
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Old 08-19-2009, 10:33 PM
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I was thinking there could be a potential knock sensor/heat sensor impact possibly, but its just an off the wall theory.
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Old 08-20-2009, 12:19 PM
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Quote:
Originally Posted by CheckedOut View Post
I was thinking there could be a potential knock sensor/heat sensor impact possibly, but its just an off the wall theory.


CheckedOut , I have my turbulators removed a year ago.Also have the SmartCraft system [ the one that monitors 64 functions , eh] and no problems or hiccups because of the modification.
If I were you, wouldn't bother removing them!
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Old 08-20-2009, 01:19 PM
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Wink Why do Merc 496's loose power??

If you are boating in salt water or your boat sits in the water a lot DON'T REMOVE THE TURBULATORS! ,the stock steel valve and seats will rust! If you removed turbulators on stock 496's and lost power or speed, something else is wrong. Suggestion- get a fuel pressure guage and read your fuel pressure at speed with the vacume line disconnected at the fuel pressure regulator, if the fuel pressure drops below 40-41 psi under full throttle you have got a fuel delivery issue and that will turn of power quickly and you will loose speed. We have found at Raylar that most guys now with the newer 496's with the newer CoolFuel Merc assemblies forget to service the filters and water disc in the CoolFuel housing and the result can be catistrophic!! Also some boat builders and riggers were installing small size restrictive anti-siphon valves on the fuel tanks and small diameter 3/8" hoose fitting and sometimes crazy fuel line routings and really creating power loss problems for 496's. You turbulators in and out are not your problem, look else where!

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Old 08-20-2009, 06:51 PM
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This might be a stupid question but wouldn't replacing the stock risers with aftermarket risers accomplish the same thing if not more?
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Old 08-21-2009, 01:45 AM
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Wink Not your Dads old mercury exhaust manifolds!

The Mercruiser 496 risers are stainless steel tubular risers with a dry joint at the manifold and a nice sweeping design. The Mercruiser 496 exhaust is nothing like the old Mercury cast wet joint riser and manifold systems. This new 496 system is very well made and quite efficient when compared to the old log manifold and riser systems. This one of the reasons we can make 525HP on these engines with our 496 kit and stock exhaust.

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PS:
Anyone who can supply nice good shape Mercury Racing HP525's for $10K each, I'll take two!
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