Like Tree0Likes

When can you use silent choice?

Reply
Old 05-11-2005, 07:35 PM
  #1
Registered
Thread Starter
 
rush's Avatar
 
Join Date: Jan 2004
Location: Reedville, va. Chesapeake Bay
Posts: 752
Default When can you use silent choice?

We have a 2000 38' Fountain 502 efis with cmi headers on it with silent choice. I've been told that you can only use silent choice while idling, is this the case? Or how fast can you run with the silent choice on?
rush is offline  
Reply With Quote
Old 05-11-2005, 08:15 PM
  #2
Registered
 
dockrocker's Avatar
 
Join Date: May 2002
Location: Deeee-troit!
Posts: 3,356
Default Re: When can you use silent choice?

I think it depends on the motor... think about it, lots of non-Mag 454's out there only have through prop exhaust and they dont' have a problem.
dockrocker is offline  
Reply With Quote
Old 05-11-2005, 08:22 PM
  #3
Registered
Thread Starter
 
rush's Avatar
 
Join Date: Jan 2004
Location: Reedville, va. Chesapeake Bay
Posts: 752
Default Re: When can you use silent choice?

Thanks for the reply. I was told with it on it was hard on exhaust valves above low rpms.
rush is offline  
Reply With Quote
Old 05-11-2005, 09:18 PM
  #4
Gold Member
Gold Member
 
Dave M's Avatar
 
Join Date: Oct 2000
Location: LaPlata, MD, USA
My Boats: 2017 30 Concept, 300 Verados
Posts: 5,221
Default Re: When can you use silent choice?

I recall seeing some systems that say not to be used above 3000 rpms.
Dave M is offline  
Reply With Quote
Old 05-11-2005, 09:21 PM
  #5
GLH
Platinum Member
Platinum Member
 
GLH's Avatar
 
Join Date: Dec 2002
Location: Burlington, VT
My Boats: Azimut
Posts: 15,267
Default Re: When can you use silent choice?

Idle
GLH is offline  
Reply With Quote
Old 05-11-2005, 09:21 PM
  #6
Registered
 
dockrocker's Avatar
 
Join Date: May 2002
Location: Deeee-troit!
Posts: 3,356
Default Re: When can you use silent choice?

I think I remember reading about the HP500 had to be open above X rpm, but for the life of me I can't remember the details.
dockrocker is offline  
Reply With Quote
Old 05-11-2005, 09:27 PM
  #7
Registered
 
Join Date: Nov 2004
Posts: 28
Default Re: When can you use silent choice?

I asked the same question to a mechanic at a Baja dealership about My 496 mag ho with switchable exhaust. He said it's ok to run it either way, just don't switch it while at the higher RPM range, He recomended to switch at idle or low RPMs...
kfm237 is offline  
Reply With Quote
Old 05-11-2005, 09:28 PM
  #8
Registered
 
Brock's Avatar
 
Join Date: Oct 2004
Location: LONGMONT, CO
My Boats: 97 FOUNTAIN 42' LIGHTNING
Posts: 15
Default Re: When can you use silent choice?

I've ran mine at 75 with no problems... I've actually heard in some cases that it's better out of the hole since you have more backpressure which gives you more low end torque.... but that depends on the engine.
I got a few exhaust tip mufflers made so I don't need to run on silent choice on the busy weekends at Lake Havasu... I'm sure the exhaust running on silent choice doesn't help out the drive temps when it's 115 degrees out.
Brock is offline  
Reply With Quote
Old 05-12-2005, 06:35 AM
  #9
VIP Member
VIP Member
 
offshoredrillin's Avatar
 
Join Date: Feb 2004
Location: Maryland
My Boats: 00 Cig Tiger,74 Cig 20'
Posts: 10,945
Default Re: When can you use silent choice?

Quote:
Originally Posted by kfm237
I asked the same question to a mechanic at a Baja dealership about My 496 mag ho with switchable exhaust. He said it's ok to run it either way, just don't switch it while at the higher RPM range, He recomended to switch at idle or low RPMs...
Same here, I had Corsa on my donzi, only switch at low RPM, you could run WO either way, just no switching above 3000...
offshoredrillin is offline  
Reply With Quote
Old 05-12-2005, 09:31 AM
  #10
Registered
 
Join Date: Jul 2004
Location: Palm Harbor, FL
My Boats: Fountain 34CC, Boston Whaler 15 Sport
Posts: 438
Default Re: When can you use silent choice?

There was a "Teague on Tech" article in Powerboat about six months ago that said motors with horsepower above 300 should have the exhaust open above 3000 RPM's.
Loan Ranger is offline  
Reply With Quote
Reply

Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
35 White Lightning
Fountain
3
11-11-2006 12:34 PM
u150
General Q & A
8
04-23-2004 08:44 AM
mfb357
General Boating Discussion
4
12-03-2003 06:30 AM
dowhat
General Q & A
4
11-12-2002 08:14 AM
edb07
General Q & A
3
07-22-2002 02:03 PM



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 09:53 PM.


Copyright 2011 OffShoreOnly. All rights reserved.