Before launch this year while running the engines to test all operation I noticed a crack in the starboard cast iron muffler. Boat is 68 31'. I put in a straight fiberglass exhaust pipe. My engines are 5.7 HO rated 330 hp. The boat was repowered in 2000 and I know over time a few ponies leave the stable. The centek muffler im looking at is rated 280hp max. Part # 1050400.  Thoughts ?

Views: 213

Reply to This

Replies to This Discussion

My thoughts, it's probably fine as long as you're not running around at 5,000rpms. The 330hp 350 small blocks aren't really much different than the 250-270hp 350's. They make more power mostly due to winding them up higher. If you have any doubts about it though I bet they have a customer support contract. 

Thanks Mike. my usual rpm is 2500. 3500 if i want to get the wind in my hair. The sound out of the straight pipe is a little severe. Heads do turn in the marina when i fire it up

Those 5.7 HOs should have 5” risers and exhaust hose in a proper application. Your boat wont have exhaust that large. (Usually about 3.5-4 on a 31) That being said Mike is correct that you will be fine so long as you’re not maxing out the engines. Especially with straight hose and no mufflers. The less restriction the better with a size issue. Keep in mind the day comes and you have to sell her you will have to advise a potential buyer.
Lee

A decision I made which I have not regretted for one moment.  I loved the sound of the cast iron, but when its time to convert look to the fibre replacements.  I converted my 31 with 350's 5 years ago and not a problem. Easy to install, everything lined up without modification, just changed out the hangers and hooked up.

Attachments:

I agree with Philip, when I changed the exhaust on my Columbia sailboat I went with fibeerglass also and was very pleased.  I admit the 4 cylinder Perkins is not the Detroits but I think like Philip you'll be well pleased doing it.

In comparison to the cast mufflers, is the sound a lot quieter?



Philip J McBride said:

A decision I made which I have not regretted for one moment.  I loved the sound of the cast iron, but when its time to convert look to the fibre replacements.  I converted my 31 with 350's 5 years ago and not a problem. Easy to install, everything lined up without modification, just changed out the hangers and hooked up.

You should be fine. My 350Q runs with dual 2-1/2 inch exhaust thru 2 Centek Vernalift  mufflers. These are very quiet, sounds a bit like a diesel. 

Check out mesamarine.com for pricing on Centek products.

p.s. Mesa's price is $232 for 1050400, compared with $300+ at other sites

Regarding the volume conversation. I entertained myself today to try and address that issue. 

While on my Commander 31 with twin 350's and fibre mufflers, fed with Rochester Quadrajet's I discovered this. Using my decibel app on my phone, standing at the helm fully enclosed here is what I found.

At 1000 rpm, idle, the decibel count was at 74. Conversation is rated between 41 and 75.

At 2000 rpm, idle, the decibel count was at 84. Tolerable, but similar to a slightly loud TV.

Have no idea what a cast muffler would be, but I will leave that up to someone else who has some.

I would also add that I talk to a passenger at a normal level while doing 7 knots at around 1600 rpm.

Reply to Discussion

RSS

Club News

2020 National Rendezvous Postponed

More information Click Here

_________________________

SuperDisc 15.0 and Resource Collection 5.0 Available Now!

SuperDisc 15.0 is an electronic encyclopedia of every aspect of Commander maintenance and repairs. The information on the disk is retrieved from the discussion forum and e-mail list, but organized in a way that makes information easy to find and use. SuperDisc is available on USB flash drive

Click here for more details https://commanderclub.com/page/superdisk

The SuperDisc 15.0 Complete Edition is for first time buyers of SuperDiscs.

The SuperDisc 15.0 Upgrade Edition is intended for those who wish to upgrade their SuperDisc 1.0 through 14.0. Each year we add over 1,000 posts. Don’t miss out.

Resource Collection 5.0 is great to own too!!!

The Resource Collection 5.0 contents include CC Catalogs and Brochures. CC Service Bulletins, CC Price Lists. Engine & Transmission Manuals. Dick Avery sketches and drawings, a folder for every Commander model, and all kinds of technical and interesting stuff. Over 193 folders and 2,697 Files. A true “Treasure Trove” for the Commander owner!

We thank you for supporting the club with your purchase of SuperDisc15.0 and/or Resource Collection 5.0. We hope you find it to be the value we feel it is, and trust you will enjoy the other benefits your payment will help provide. It’s your payment that helps to support the activities of this dues free organization that has grown from 12 members in 1999 to well over 4400 members in 2020.

To order now click here!

_________________________

2019 Annual Photo Contest Winners

Sixty-Eight photos were submitted for this year's contest.  They were absolutely amazing, making selecting a top 3 an extremely difficult task for your Executive Committee

Thank you to all that submitted a photo to the contest and even if your photo was not in the top 3, it could appear on a cover of Styled In Fiberglass, the club's newsletter due out in November, or the 2020 Wall Calendars, which are now available.

2019 Photo Contest Winners

Past Photo Contest Winners

2019 Photo Contest Entries

_________________________

     

© 2020   Created by CCCC Webmaster.   Powered by

Badges  |  Report an Issue  |  Terms of Service