Anyone interested in the ultimate Amphicar muffler project ?

[DavidC]

In my new parts stock I have a late spec muffler. Now there have been many muffler options for Amphicar over the years, some better than others but all are noisier than ideal. I have been talking to an engineering company today who know how to make mufflers near silent without sacrificing horsepower. I am going to have them make one for me. It'll be stainless and to original dimensions (they will copy this one) so it will look and fit perfectly - especially around the important seal on the back panel where the exhaust comes out. I'll have them enlarge the inlet pipe in to the muffler so it can cope with my 1300 but it would work just as well with a stock 1147 - there would be a choice of U shaped pipes.
Now I don't know exactly how quiet it will be but having seen their work I'm hopeful it'll be a lot quieter than any other Amphicar muffler out there. Modern cars have to meet certain db levels and there is a lot of knowledge in this area now.
I also don't know price - but it will be expensive, my guess is between $500 and $1000 given the work, it will be hand made in the UK, shipping would be straightforward, the company already ship systems all over the world.
Anyone interested ? Let me know.
(There is no commitment until I have a protoype working well and final pricing for a batch !)

 

[jfriese]

Hi Dave,

I'm a bit curious about the angle of the exhaust pipe. I have always had the pipe come out of the car exactly level and let the chrome end piece adjust to the angle of the rear panel. This has always looked right to me and I've never had an issue with water coming in. Your pipe has such an angle to it that it wouldn't come out anywhere close to level. What's your thinking about this?

John Friese
67 White
67 Red

 

[SNOWBIRD]

In pic one I have a std muffler that I custom fit to each Amphi I restore, They are Very Quite. I even had a Quite shoot out at Celina one year and won!
in Pic 2`, I had a original muffler and welded the ends to my replacement muffler. This car will be at Celina this year.( originals that came with most cars had round ends)
you can see in the car that muffler is on a slant so exhaust pipe HAS to have the bend like Daves photo for it to come out the rear level.

 

[mike_israel]

I always thought the original mufflers had the rounded ends? Was there more than one type from the factory?

I think there is a market for a high quality, stainless reproduction. Beyond $500 might be a tough sell.

Could always go full ricer. HaHa

 

[DavidC]

Bullet type exhaust was only early cars. The later ones (which are more common here) had the square end type as in my pic. There was at least one other slightly smaller style muffler that Amphicar tried.
All have that kink John. Reason is the pipe then emerges perp to the back panel, no tilt on chrome tailpipe - that makes it easier to seal. I've had that seal below the water line a few times on steep exits, it needs to seal well !
Gord, that 90 degrees bend on the inlet pipe will be a big part of making your muffler quiet - making the gases change direction is how they muffle - but too sharp a change saps power.

 

[Jon March]

David, Gord, etc - After seeing 75 Amphis in Celina, I can say mine is one of the LOUDEST, and most annoyingly "metallic" sounding ...like a tractor!!
I want as quiet as possible!!
I see a lot of videos on youtube about muffler re-packing on motorcycles (ceramic wool, etc).

Is it possible that could be bad or missing in my canister muffler?
What do they look like inside - and why are some nice and quiet?!

listen to the exhaust here - and thats from a distance!!

 

[Midwest Amphicar]

I want a quiet muffler!!!!! Stainless for my 1300 !!! Dave send me a prototype to USA test!!

 

[Jon March]

Gord won the decibel shootout awhile back he says...

 

[Jon March]

David - Is there a time when you will have a gathering of Amphicars there... where you can take a decibel meter to take a few different level-readings, at a few different rpms?
(at a two meters is prob best/most real-world) And take pictures of each muffler for reference
Then you will be in the best position and a "baseline-to-beat" to demonstrate the sound-improvement when you put the new prototype to the same test

How soon before you might be able to illustrate this exciting idea?

 

[DavidC]

db numbers would be good, project on hold for now, the people making out of mild steel are too busy and I've had my stainless one reworked to make it a bit quieter - but still not where I want it. I will pick this up again at some point.

 

[peterboz]

made a repro off the old exhaust in stainless steel

 

[peterboz]