Stretching rubber

[Project_Mayhem]

The smallest rigid exhaust hose that I've been able to get on my riser is 1-5/8". The actual exhaust outlet is 1.75". The inlet of my muffler is 1.5". There is exactly 12" between the riser outlet and the muffler inlet. Which of the following options would be the most reliable?

• 1.5" soft wall hose. I assume it will stretch much easier than the wire reinforced rigid? This would be my preferred method
• 1.75" hose, 1.75" to 1.5" barbed coupler, short piece of 1.5" hose (most expensive method)
• 1.75" hose, barb, short piece of silicone hose rated at 500F

Even with 1-5/8" I'm getting some leakage at the muffler inlet. It'd be nice to have a dry bilge for once

 

[Tally Ho]

Can you buy a silicone hose that is tapered to fit properly on both ends? I think I have seen hose that is 1.5” on one end and1.75” on the other (or whatever you sizes are).

something like this….

ETL INDUSTRIES ID 1.5" to 1.75", Length 3" Silicone Reducer Straight Coupler Hose, 4-Ply Reinforced Universal Intake Reducer Intercooler Pipe Black https://a.co/d/c8FaPsg

Greg

 

[Project_Mayhem]

The longest I've seen is about 9" for silicone adapters. I've seen radiator hoses with a temp rating around 250F that are the right sizes and length but I've heard many mentions of reasons why it shouldn't be used. I'm thinking that if a 1.5" softwall exhaust hose can be stretched to 1.75", then I can do this connection without any couplers and additional failure points. Just looking for a little bit of confirmation before purchasing.

 

[dlochner]

Centex makes all sorts of exhaust parts including fiberglass reducing couplings. If I remember correctly Ordering gets a little confusing as the sizes are the OD, not the ID.

Reducer Couplings - Centek | Fisheries Supply

Save More on Your Centek Reducer Couplings at Fisheries Supply. Excellent Customer Service, Ready to Ship. Marine Supplies Since 1928!

www.fisheriessupply.com

Centek Marine - Custom Marine Exhaust

Centek Marine is the premier designer and manufacturer of the best marine exhaust systems and components for the best boats in the world.

centekmarine.com

 

[Tally Ho]

The longest I've seen is about 9" for silicone adapters. I've seen radiator hoses with a temp rating around 250F that are the right sizes and length but I've heard many mentions of reasons why it shouldn't be used. I'm thinking that if a 1.5" softwall exhaust hose can be stretched to 1.75", then I can do this connection without any couplers and additional failure points. Just looking for a little bit of confirmation before purchasing.

I don’t know how “stretchy” any of the exhaust hose is…even the silicone may not stretch much.

Greg

 

[dmax]

I don’t know how “stretchy” any of the exhaust hose is…even the silicone may not stretch much.

Greg

Agree - I have a 1.5" silicone hump hose and I don't see it stretching to to fit 1.75". It bends but doesn't stretch much.