stupid question - where do my tailpipes go?

[Nate@BLI]

5.2 magnum in a 67 valiant. just got the engine and Doug's headers fitting right: Magnum 5.2 & Doug's D453 Header Fitment Issues

now moving onto fabbing up the exhaust. i have the flowmaster 15826 tailpipes. i spent some time test fitting them and have a few questions.

it kinda seems like they designed these tailpipes maybe without a fuel tank in place. the driver side fits great - mostly because the fuel tank is offset towards the passenger side. so, driver side fits great and the tube wants to be right under the frame rail.

on the passenger side, the tube can't be as tucked up under the frame rail because of the fuel tank strap hook bolt. the hook bolt being in the way pushes the tube outward quite a bit. i'm considering changing this to a different bolt arrangement to something that is captured on the bottom of the frame rail instead of hooked through the side.

so the main big question i have is where should the tail pipes go relative to the rear sections of the frame rails - say near the spare tire well? inboard, outboard or directly underneath?

other question. the tailpipe turn downs. should those be angle straight longwise or turned inward or outward? i am assuming they should not be angled in or out and should just be straight.

in the axle arch part of the frame - are the tailpipes more under the frame rail our more outside the frame rail?

words are welcome but pics are greatly appreciated. thanks!

 

[Nate@BLI]

ok i whipped up some reference pics courtesy of the flowmaster website.

turn downs - angle out, in (like shown), or straight?

i didn't ask this in my first post but also wondering if this portion should be parallel with the frame rail or angled down?

i'm assuming plenty of folks have installed these tailpipes before. would love to see how others did theirs.

 

[HemiSSDart]

You just learned something about aftermarket exhaust. 67's are unique because of the single strap across the fuel tank, 68-76 have dual straps front to back. Also, the factory tail pipes are only 1-3/4 diameter on even the 383-440 A-Body's. All that combine makes it difficult to use aftermarket tail pipes. I don't know the answer, only that I have had a couple of 67 Dart GTS's with the 383 and dual exhaust and even that was tight with the much smaller tail pipe diameter...

 

[Nate@BLI]

i really appreciate the insight! that's super helpful to know. stupid question - it's not impossible to change my '67 to the '68 style with dual straps is it? are the spots the dual straps mount to also on a '67 car?

 

[dadsbee]

Wife's '67 383 Formula S.. Yes I know the tips aren't factory.

 

[HemiSSDart]

i really appreciate the insight! that's super helpful to know. stupid question - it's not impossible to change my '67 to the '68 style with dual straps is it? are the spots the dual straps mount to also on a '67 car?

They are built into the trunk floor, you would have to get a parts car and weld them in I believe...

 

[mopar head]

I used tti system and they put the pipes under the frame rail which put the pipe exiting center of the factory cutout. The right side didn`t have the cutout, but would wind up under the rail also, and slam up against the tank hanger like yours too.
I devised a bracket that hangs from the inside of rail towards tank and turns under. There was a factory hole in the outside of frame that I transferred through, I then enlarged the outside hole to accept a deep well socket. The bracket I welded a crushed lock nut to "I think". Another words It was a royal PIA to get that pipe equidistant on the car but turned out good and is still hanging in there, pun intended

 

[Ricks70Duster340]

i really appreciate the insight! that's super helpful to know. stupid question - it's not impossible to change my '67 to the '68 style with dual straps is it? are the spots the dual straps mount to also on a '67 car?

Before you modify the tank setup, I would take your car to a custom exhaust shop and have them make a few changes to the bends and install them for you. They are in that business and have the expertise to get it done!

 

[krazykuda]

Tailpipes go in the back...

 

[LO23M8B]

Anywhere you want, they are your tail pipes.

 

[dano]

Are you using the correct muffler? Those are for offset/offset mufflers, not the stock offset/center mufflers.

https://www.holley.com/products/exh...ct_fit_pipe_kits/prebent_tailpipe/parts/15826

 

[JDMopar]

i really appreciate the insight! that's super helpful to know. stupid question - it's not impossible to change my '67 to the '68 style with dual straps is it? are the spots the dual straps mount to also on a '67 car?

I doubt the holes for the straps are in the upper crossmember above the front of the tank, but you could put some there. Then you will need the bracket that welds into the trunk floor spare tire hole that provides the mounts for the J bolts in the rear. AMD has those brackets. I plan on doing this very thing to my 65 Barracuda to get that lousy side to side strap out of the way for my passenger side tail pipe. I'll be getting a new tank anyway and have a few A body tank straps laying around, so it won't be that difficult. I want true dual exhaust on my Barracuda, and will more than likely use exhaust tips that I bought for an E body Cuda, and just cut another slot for the right side tip in the rear valance.

 

[64mopar]

Under the car.

 

[Nate@BLI]

some real comedians on here.

thank you dadsbee for the pics. very helpful.

making a couple little brackets for under the spare tire well and a couple holes in the crossmember is way easier that trying to tweak the tailpipes. regular exhaust shop isn't going to be able to re-bend mandrel bent tailpipes without making crushed bends and i'm not interested in doing that. i'd rather make some minor mods to use the pipes as they are.

dano - yes i have the correct mufflers but mufflers don't even matter at this point. i'm just test fitting the pipes without mufflers. the position of the tailpipes will determine where the mufflers go, not the other way around.

 

[dano]

some real comedians on here.

thank you dadsbee for the pics. very helpful.

making a couple little brackets for under the spare tire well and a couple holes in the crossmember is way easier that trying to tweak the tailpipes. regular exhaust shop isn't going to be able to re-bend mandrel bent tailpipes without making crushed bends and i'm not interested in doing that. i'd rather make some minor mods to use the pipes as they are.

dano - yes i have the correct mufflers but mufflers don't even matter at this point. i'm just test fitting the pipes without mufflers. the position of the tailpipes will determine where the mufflers go, not the other way around.

Well your getting the result you would get without the mufflers and rest of the exhaust installed loosely. It will be a mystery until things become more constrained.