Perfect Exhaust for a GT500 1967 that has more hp and gets driven

[Kent]

I actually have another engine in my GT500 that I built for driving it and testing my engine skills, appx 420 hp+ at the moment I have a 3" stainless exhaust under the car but that is to loud and wild, I would like to have something under the car that looks and sounds more stock I also want to to attach the original exhaust manifolds to look more stock any ideas for a nice exhaust? The Scott Fuller parts are nice but really expensive when you drive the car like I do. And I´m scared that they will rust fast with the bare metal look.

[shelbydoug]

https://www.summitracing.com/search/make/ford/model/mustang/year/1967?keyword=flowmaster%20exhaust%20kit%20for&ar=1&kr=flowmaster%20exhaust%20kit%20for%2067%20mustang

These have a nice sporty rumble to them but are made to mate up to headers.

[deathsled]

"Loud pipes save lives" as it is said. I'd keep the loud stainless if it were me. However there is a clear coat rust proof if you want to change it out.

"Shark skin clear coat" typically refers to Sharkhide Metal & Aluminum Protectant, a highly durable, clear coating designed to protect metals, fiberglass, and painted surfaces from oxidation, salt spray, and corrosion. It dries to a clear, flexible finish that does not yellow and can last for years on boats, RVs, and metal work.
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Sharkhide Store
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Key Aspects of Sharkhide Protectant:
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Finish: It provides a clear, often "wet-look" appearance on bare metal.

[jguyer]

I have a '68 GT500KR convertible, the first replacement exhaust I used was a '70 Boss 302 system. Connected to the existing H pipe (which is still on the car). Was nothing like original, no transverse muffler. Latest is Flowmaster system, but personally don't like the hollow drum sound. '67 and '68 are similar, but don't know if this will work for you.

[S412gofast]

On our GT350 #1341 we installed the following system.  All componenets fit well together.

Exhaust system is made up of components from a few sources vs going with the entire Scott Fuller system.
Factory Hipo exhaust manifolds
H-pipe and mid pipes are from Precision
Tail pipes and Chrome Tips are from Fuller
All clamps, brackets and hardware are from Fuller
Hi flow transverse muffler are from Waldron and it sounds fantastic!

[Bob Gaines]

I actually have another engine in my GT500 that I built for driving it and testing my engine skills, appx 420 hp+ at the moment I have a 3" stainless exhaust under the car but that is to loud and wild, I would like to have something under the car that looks and sounds more stock I also want to to attach the original exhaust manifolds to look more stock any ideas for a nice exhaust? The Scott Fuller parts are nice but really expensive when you drive the car like I do. And I´m scared that they will rust fast with the bare metal look.

Scott has alternatives like aluminized so it will not rust as well as bare steel.

[WT6066-2600]

Had a 68 KR with the 2 ¼" original exhaust (h pipe, intermediate resonator pipes, and tail pipes) but without the transverse muffler which was replaced with a fabricated spacer made from exhaust tubing.  Ran many SAAC convention track events (road and high bank ovals).  Good performance and enjoyed the 150+ MPH on the ovals.  Low throaty exhaust tone was pleasant when idling or at speed.  Send a PM with an email address if you want a short video of sound.  Good luck

[Bob Gaines]

In the past I have salvaged/repurpose the two uniquely shaped factory step down resonators which are aluminized from from the factory and typically survive intact when the rest of the factory exhaust rusts away . I have the the muffler shop bend and weld up new aluminized pipe in 2 or 2 1/4 inch (depending on what I want at the time) and run it to a aftermarket transverse muffler. For this type system it is better to use the repro exhaust tips . I use original hangers and aftermarket nickerson heavy duty muffler clamps that are shaped like factory . This way looking under the car the system has the look of a original system . At least that is what I have done on driver cars in the past. The key is the salvaged /repurposed resonators which have the unique look compared to the typical bullitt shaped ones. If wanting more original go with a complete system from Fuller. Any compromise like headers or other aftermarket components no use going with the Fuller intermediate pipes etc. because you are missing the point and just wasting money that could be better spent on the car elsewhere. At least that is my viewpoint.

[98SVT - was 06GT]

I'd swap the mufflers first (I'm cheap)

https://www.youtube.com/watch?v=JcqJmwaDfYE

[Kent]

Yes it's difficult, when I will built the 428 for the GT500 it could be that it will also reach the 400+ hp easily without seeing it from the outside and using pretty much all original parts. So the original GT500 Exhaust with 2" would be a bottleneck and that really sucks.

But The idea from WT6066 to delete the muffler is really good so I have a stock looking exhaust from manifolds to the rear end and only need to swap the muffler in if it's necessary, do you maybe have a picture of your adapter?

The idea from S412 is also great but maybe not exactly what I want to reach. For originality I would like to keep it bare steel but as we all know exhausts are rusting also from the inside so aluminized is maybe not helping that much. Only thing that would be maybe an option is VHT Clear Coat for high temps. I think I need to do some tests.

[WT6066-2600]

Kent,

The spacer that we fabricated was a DIY "afterhours" effort in a SEARS Auto Center.  The plan was to bend the tubing then weld the pieces, unfortunately SEARS didn't have the right size mandrel.  So, we went "basic" with a ladder style weldment of straight tubing.  Car sounded nice and performed while enough to chirp the tires and run 150+ MPH at Atlanta and Charlotte bank ovals.  Sorry, no pictures but check the attachment.

While I don't have the car anymore, the spacer is still in the car and functioning decades later.  Bill Collins is currently listing the car for a customer, beautiful Royal Maroon (sLime Gold repaint) 68 KR fastback.

[Bob Gaines]

Yes it's difficult, when I will built the 428 for the GT500 it could be that it will also reach the 400+ hp easily without seeing it from the outside and using pretty much all original parts. So the original GT500 Exhaust with 2" would be a bottleneck and that really sucks.

But The idea from WT6066 to delete the muffler is really good so I have a stock looking exhaust from manifolds to the rear end and only need to swap the muffler in if it's necessary, do you maybe have a picture of your adapter?

The idea from S412 is also great but maybe not exactly what I want to reach. For originality I would like to keep it bare steel but as we all know exhausts are rusting also from the inside so aluminized is maybe not helping that much. Only thing that would be maybe an option is VHT Clear Coat for high temps. I think I need to do some tests.

I have used before some pipe out there that is a high carbon steel that like stainless does not rust however it has the look of aluminize which is slightly shinier than the regular steel pipe but not the shininess of stainless steel.  A magnet will stick to this high carbon content pipe  which is the typical test to check for stainless (magnut does not stick to stainless).  Your VHT high heat clear idea will have disappointing results because the clear will start to yellow when exposed to heat cycles plus is also becomes somewhat tacky and attracts dirt. 

[Kent]

Thank you Bob thats a very good info. Ok so I´m now really limited as I drive and use the Shelby. The Scott Fuller Parts are top notch definitely but for a driven Shelby even if it's just maybe 100-200 miles a year it's difficult. What would be the closest to stock exhaust incl downpipe / H pipe to buy at the moment thats sound nice. I like the idea of having something like the exhaust from Waldron/ Arvinode as they are just tubes and have no real muffler.

[vtgt500]

In the 49 years of owned my GT500 I've had about 1/2 dozen exhaust systems.  For the past 20 years I have been very pleased with the current choice.  Ceramic coated, SuperComp headers,  Extended, 3" - 2-1/2" slip-on, tapered reducers, MagnaFlow 2-1/2" system with their X-pipe and original, exhaust tips.   As quiet as most any other car for in-town traffic. At 60 MPH you can have a quiet conversation in the car with the windows down.  On a deserted interstate at 140+ MPH the solid lifter, dual quad, side oiler is ROARING with no hint reduced acceleration.  Best of all, it fits perfect and zero rust.

[Shawn]

Magnaflow makes a Turbo muffler in stainless.  Doesn't have the droan or typical bad noise associated with the chambered mufflers.  Doesn't say magnaflow on the muffler but is made by them in the USA.  I'm running Dougs long tube with H pipe and the car sounds like a 60's muscle car should hands down.