Super Jet Tube Diameter & Exhaust Restriction

L

LeftysRule22

Location
Austin, Tx
Bear with me, I searched and came up with nothing.

I want to add an inline silencer to my exhaust routing under the tray (I hate loud skis). The silencer i picked up has roughly 1 3/4" OD with the ID being slightly smaller. Im nervous to run this one because once I button up the tray I do not plan on opening it ever again. Im using 2" sch40, and it just so happens that the 2" to 1.5" rubber couplers for PVC fit the 2" sch40 and silencer perfectly (since 1.5" PVC OD is around 1.8"). Looking down the tube, it just looks like a massive diameter drop with the silencer. Add the volume displaced by water, and things are starting to get skinny.

So for a built 701, what is the smallest diameter exhaust you can run without affecting power? I figure Yamaha chose 2" (SN) for a reason, and Id hate to handicap my motor. (But then again, I haven't noticed any different outlets on the 1100cc boats? Even seen people pushing in smaller pieces to fix that left turn bog problem? :ugh: )
 
Cannibal

Cannibal

Tasty Human
Location
Summit Lake, WA
Have you ever seen an exhaust tube for a 750sx? It's basically an inline silencer built into the tube. I have one at home I plan on using in a future project I can snap a pic for you if you want. I think they are 2".

Alternatively, you could use one of THESE either inside your engine compartment or place it under the tray. I need to build an exhaust tube for my SXR and I've thought about welding one in line.
 
L

LeftysRule22

Location
Austin, Tx
My old 750 is what gave me the idea for this. I had a coffman exhaust with no water box for a short period and it really wasn't that loud. So i figure with a stock waterbox and silencer my 701 should be pretty tame.

I almost bought a TDR but I got this 12" coffman for cheap.

Also tried adding a water fitting after the waterbox on my fx1, but it wasn't much of a difference.

Sent from my 3VO
 
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