Try at my own GenIII Coupe side-pipe setup...

[Dave Tabor]

This is GenIII Coupe #17 with a FRP 302, 345hp, B-cam, carbureted.

The FFR pipes are loud and I don't dislike my neighbors.

Goals:

decrease in sound level
minimal blockage of the 4 header-out tubes- or at least block them all evenly.
space to weld in an O2 sensor bung to meter at least one bank of 4 cylinders.


The flanges are custom-cut with a 4 inch center hole. Into this goes a cut-off 4" elbow. Yes, I will cut the center of the 4-hole gasket out. It's $40 a side to get this far.


I can get any angle I want, in-out / up-down, banging it around with a dead-blow hammer, and grinding off the excess from the inside. Welding will happen on the inside of the flange. I did a quick few spot welds (flux-core) just for this test.


I did a really quick setup today just to see if any of this would take me in the right direction. I had a bunch of mufflers sitting around. The dB meter was 3 feet away. Idle tests only for today. I did not have turnouts which may change things for better or for worse. FFR pipe was always present on the passenger side.


Looks like the Flowmaster Slimlines will work for me- not a surprise as they have been all over the forums for a while.


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Video comparison here:


https://youtu.be/aUiSJYkpvXE


Dave
GenIII Coupe #17

[David Williamson]

Interesting post, I will also be changing the side pipes. I found the FFR side pipes are far too loud, my Cobra sounds like a Rolls compared to the Coupe. OK it is a different engine the Coupe has a Levy Dart 363 and the Cobra has a warmed up '93 GT 5.0 in it but still... When I did a slow go-cart ride at about 20 mph 1500 rpm I could not talk to the passenger.
Keep the information coming. I suspect others will be changing the side pipes too.
David W

[Jeff Kleiner]

Thanks for the info Dave! Something similar is on my radar for an upcoming Gen3 build, not just for of the noise factor but reportedly the Coupe's 4 into 2 pipe design is a huge power robber.

Jeff

[Jacob McCrea]

Thanks for posting this, and please keep the information coming. I think I will be doing the same since my Gen II side pipes won't even slide onto the headers without re-welding or expanding them.

[Bob Brandle]

Dave,
I'm still waiting to receive my Gen 3 Type 65 Coupe with a FFR Aug-11 target production date complete, so maybe I'll receive it around the end of August or early September.
In the mean time, I'm planning my built out and preparing for the arrival.

Instead of keeping one aspect of my car's design secret until it takes shape in my build, here's what I'm currently planning for the exhaust for the Gen 2 Coyote 5.0 with one of the key design goals to reduce the loudness of the exhaust:
Coyote Shorty Headers > Pypes MiniCat > Custom J-Tube > 30" Flowmaster Slimline Sidepipe Muffler > Angled Exhaust Outlet Pipe.

This will be a single thick diameter sidepipe arrangement.

Here's a trio of Photoshopped concept images that I put together from online product images and other people's Type 65 cars. I hope that it shows what I'm thinking of. I do realize that the Coyote Shorty Headers are not likely as effective as the 4 into 4 FFR but they do provide the pipe length to add in the Pypes Minicat. I'm already sold on the attributes of the single Flowmaster Slimline sidepipe muffler per side and can deal with not having the more period correct twin sidepipes per side. This is all about compromises and hopeful other benefits obtained.

Bob

[Dave Tabor]

Folks,

I will keep this updated- my body/nose are off right now and I'm trying to finish the fill/sanding bit this week.

I can certainly dyno the car with both sets of pipes- I'm curious enough do spend the ~$200 to do it.

Bob, just wondering- why the Minicat and not some short 'bullet' muffler? Is it an emissions thing?
What you're doing looks great- thanks for sharing.

I'm not at all caring about the loss of the double side-pipe look- most folks (sadly) these days don't even know what an original Coupe is.

Dave

GenIII Coupe #17

[Bob Brandle]

Dave,
There is no emissions issue that I'm trying to solve or trying to meet with the mini-cat. The Pypes Minicat does have the needed oxygen sensor port for the Coyote 5.0 that I'll be installing, should provide some noise reduction, looks good or OK at least (if something extra is going to be there), should eliminate or reduce non-cat exhaust smell (though this isn't really an issue or point for the minicat) and isn't that expensive given that I'm also having the custom Flowmaster sidepipe muffler. A small bullet muffler would likely provide some of these benefits, but what about the oxygen sensor port?

[John Dol]

There's a thread that shows Mark Dougherty making a set of dual pipes with new mufflers that reduce sound and flow better.
Check out his link

https://thefactoryfiveforum.com/show...muffler-source

The raptor pipes are nice too.

John

[65 Cobra Dude]

Another option to consider is the Boig Motorsport sidepipes and headers. I have them on my Gen III with a Coyote motor and it is much quieter with no loss of HP. They can make for any motor and are currently looking for a Gen III with a small block to mock up.

Thx,

Henry

[thriftychicken]

I'd love to have something quieter than the FFR side pipes. I have a Gen III with a 408 Windsor with the 4 header pipes that run into a wall (side pipe flange). I need to keep an eye on this thread and see what options get mentioned. Raptor looks good but would also like to see what Boig might offer.

[GoDadGo]

Hey Gang,

Have any of you looked at Spintech for your Daytona Coupe leg burners?

https://spintechmufflers.com/5-oval-...daytona-coupe/

Looks like they are really trying to give you Type-65 guys a super cool solution.

Steve