GT/CS and dual exhausts

[CraigB]

Which GT/CS's came with dual exhaust (with the twin tips and valance cut out). Was it an option or specific to certain engine choices?

CraigB

 

[teamlo]

J-code 302 4V (with GT Equipment Group), S-code 390 4V and R-code 428 CJ 4V would have had factory dual exhaust with the valence cutouts and the twin tips. This is to the best of my knowledge but I am not claiming to be "all knowing".

Terry

 

[GTCSMustang]

Terry,

You are correct. The 302/390 had 2-inch exhaust and the 428 had 2.25-inch. The H-pipe, resonator pipes, muffler, and tailpipes were different between the 302/390 and 428 but they all had the twin-tips sticking out the back.

Scott

 

[franklinair]

My experience with the repro GT valances= they don't fit worth a hoot.

Neil

 

[PNewitt]

If you had a non-GT car with a C-code engine, you could get a dealer-installed dual exhaust, but it had the turn-down tips in front of the stock rear valance.

If an original owner of this type of CS (or other Mustang) wanted the GT valance, I suppose a dealer could get the parts, paint the valance and set it up for the customer (except for the six cylinder).

I understand the factory setup, but I think that if you aren't too concerned about "concours" detailing, I'd go for it., because the whole back end, looking like a Shelby GT, kinda demands the dual exhaust--with cutouts look.

Personally, when I see straight pipes under a stock valance, it kinda makes me nuts, because the cutouts and dual chrome tips look so cool; like they belong there.

Paul N.

 

[teamlo]

I forgot to mention, the X-code 390 2V would have the duals with valence cutouts if it had the GT Equipment Group, though I can't say as though I've seen an X-code GT in person (I have seen one or two in magazines).

Terry

 

[CraigB]

I have to agree that the rear end with the cutout and dual chrome tips just finishes of that Shelby rear look.

Would a J-Code WITHOUT GT equipment group still have the dual exhaust as standard?

Not that it matters if it is factory or not, it looks too good not to have it regardless.

CraigB

 

[teamlo]

J-code without the GT option should have single exhaust I believe.

 

[robert campbell]

Terry,
From what I have experience over the years, you are right on. A friend and I went on a GT expedition in the mid 80’s. All years from 65 to the last 69 GT. The parts pieces and engine requirements from year to year.

We had some fun with the dual exhaust option and the GT. This is more for originality in this case. Looking for the elusive “true” (from the factory I guess, never figured out what true was) GT. We had quite a few 67 GT’s around that had some pedigree that they were from the factory. One item we noted was the most rearward exhaust hanger, by the back end of the leaf spring, bolted through the frame rail all the way through in from side to side. A threaded capture nut would have worked fine on the outside of the frame rail. What we also noted is that the RIGHT side always had a “spacer” inside the frame rail to prevent “distorting” or “crushing” of the frame rail by over tightening this bolt. To work with single exhaust cars. Then we looked at a bunch of 67 cars without the GT option or dual exhaust. Found that the LEFT side frame rail in all cars checked did not have this spacer. Went to the 76 dual exhaust cars and found this spacer in all left side frame rails of these cars.

Interesting note about 67 is that to my knowledge the dual exhaust was NOT part of the GT option that year. Then in 68 it came back and was part of the GT option group. But in 68 they dropped the front disc brakes, that was part of the 67 GT option group. Go figure…

Anyway from what we found, if your car has the spacer in the left side frame rail, it came from the factory with dual exhaust from this small survey of cars. Of note, being in the NW they were all San Jose cars. Who knows what Metuchin did… Of note my GT/CS has the spacer in the frame rail and all indications of factory dual exhaust, although we did not look at any single exhaust 68 cars.

More fun in the history of our cars!

Rob

 

[Midnight Special]

J-code without the GT option should have single exhaust I believe.

...My J-code (302 4v) had the original single exhaust. I added the dual exhaust w/ Flowmasters. 'Love it!



P.S. Nice "car'cheology" as always Rob!

 

[HappyHour]

...My J-code (302 4v) had the original single exhaust. I added the dual exhaust w/ Flowmasters. 'Love it!



P.S. Nice "car'cheology" as always Rob!

Ditto...mine was a J Code non-GT, but born again with dual quad tip and valance cut. Soweeet.

 

[robert campbell]

While we are on this exhausting subject.... I built a 67 Mustang coupe with the GT/CS trunk lid and end caps. Did not put the taillights in. It was a six-cylinder car and I put a top loader 4 speed behind it. Single exhaust that I cut off even with the bottom of the rear valance lip. Anyway, the fit of the aftermarket fiberglass trunk lid and my trunk seal were not all they could be. Bit of a leak. Well with the spoiler trunk lid that creates a bit of a vacuum behind the car…. Yup, lots of exhaust smell.

A bit of more fitment and so on and I got a good seal and smell went away. Anyway, GT/CS cars need good trunk seals.

Ever look our the back on a cold morning during warm up (lots in the Northwest) and watch the exhaust vapor “swirl” behind the car at about 25 mph??? I love it!! Great part of the GT/CS trunk lid. Not as prevalent behind a Shelby Fastback. Had a 68 GT-500 KR and it did not create as much vacuum as a GT/CS!!

Rob

 

[teamlo]

Yes, Ford did some odd things back in the day. Duals on GTs through '66 (and 4V engine was required), but then for '67 they let the 289 2V go into the GT. But then for '68, back to 4V engines only, but then they let the X-code 390 2V go into the GT. Weird.

'68 is by far my favorite year.

Terry

 

[gazrox]

Has anyone done the Shelby "pipe within a pipe" exhaust tips and the GT cutout valance? I'm thinking of doing that instead of the twin GT tips. Post some pics if anyone has - would like to see that!