Hi everyone,

Was at the boneyard today getting some parts for my 85 manual duke. The car I was pulling from was an 85 automatic v6. I pulled the exhaust from where it comes out of the cat. convert onward. Can I put this on my duke? Does it effect performance, line up with everything, use the same hanger/springs, etc?

Easy to put together, probably no performance gain, the tips may be tight in the exhaust cutout. Do you have a cutout on the right side?

Performance wise that's fine...I honestly just didnt want it to hurt performance...i simply like the way it looks :-D. Also, I do not believe it has the exhaust cutout..which i guess means ill be cutting up the back.

Yes it will bolt up. It does sound better than the single exhaust. I did it on mine. While you're there, get the rear bumper, egg crate, and rear halfs of the wheel wells. Everything bolts up. Be sure to get the red side marker lights too.

Jonathan

The previous owner had put a GT rear bumper (as well as other newer panels) on my '84, but I hated the way the twin cutouts on the GT rear bumper looked with one set of tailpipes.

A trip to the wrecking yard took care of that. Here is a hybrid GT/duke exhaust that a club member and I put together. The 4-banger never sounded so good!

Yep, I too have GT cat back system on my 4 cyl. That I got free from a member here. Helped cut down on my exhaust leaks a lot, making my exhaust quieter. Plus I have an 88 coupe, so no more empty, right hole in the bumper.

I have borrowed the above picture to show how I put a V6 muffler on my 88 4-cylinder:

I cut it, and my old exhaust about where I have indicated in the picture, and joined the V6 muffler to the old pipe with a sleeve and clamps. The V6 muffler, as I got it, didn't have much more pipe than that on it anyway. Where I joined them, the pipe has a small straight section.

quote Originally posted by TopNotch: I have borrowed the above picture to show how I put a V6 muffler on my 88 4-cylinder: I cut it, and my old exhaust about where I have indicated in the picture, and joined the V6 muffler to the old pipe with a sleeve and clamps. The V6 muffler, as I got it, didn't have much more pipe than that on it anyway. Where I joined them, the pipe has a small straight section.

That is actually where I cut and joined mine. The cat back I got was an aftermarket that had crimped slip joints. I undid the slip joint right about where your arrow points and shoved my stock system in there. I still have the exhaust clamps I planned to finish the joint off with in my bedroom.

The only drawback to where you fellas have indicated you cut your pipes is that you've introduced another joint, another connection, another potential place for a leak.

As you can see in my original image, my V6 exhaust system goes all the way to where the factory cat used to be located.

Either way though, it's a fine improvement over the original duke exhaust with the single set of tailpipes.

quote Originally posted by Archie: Our latest V-8 swap car arrived at the shop Saturday. It's an 87 4 cylinder 5 speed coupe with only 37000 miles. It's owned by a member of this Forum. What make this one notable in my book is that he is the original owner & bought the car new in 1987. Now the part that is strange to me is that it's a 4 cylinder coupe but came brand new with the Aero body style like 1986 SE only with the black paint on the lower aero trim. I've been around Fieros for 20+ years & never saw an 87 Aero Coupe with a 4 cylinder engine in it. Someone tell me I'm not crazy. Archie

quote Originally posted by Archie: Give it up for factory dual exhaust on a 4 banger

The '87 SE (which this is) was available with the 6 or the 4. I have seen a few others.

Jonathan

I thought this was common knowledge, but apparently was mistaken.

Some models of 4cyl Fiero (like the SE) came with the dual-outlet muffler from the factory. The only difference between the single and dual outlet mufflers is the presence or absence of the second outlet pipe. In other words, the V6 cat-back exhaust is "plug-n-play" in the 4cyl exhaust system (no cutting necessary, if the parts are in good condition). Your only concern is whether or not your rear fascia has the cut-out for the second exhaust outlet.

quote Originally posted by jasedude: Was at the boneyard today getting some parts for my 85 manual duke. The car I was pulling from was an 85 automatic v6. I pulled the exhaust from where it comes out of the cat. convert onward. Can I put this on my duke? Does it effect performance, line up with everything, use the same hanger/springs, etc?

Yup. That's what the 84 Indy had - 4-cylinder Duke and dual exhaust.


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My World of Wheels Winners (Click on links below)

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[This message has been edited by fierosound (edited 02-21-2010).]

My 88 has twin cutouts but only a single exhaust. The PO simple put a dummy exhaust tip under there clamped to the bodywork. Looks fine and who's to know!

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Dave

www.ltlfrari.com

Well then, it seems like I made the right decision in nabbing the exhaust system. My dad thought I was crazy, insisting that the single exhaust system already on my car was perfectly fine. Which is more or less true...but it doesn't look as cool in my opinion. I'm going to do the swap tomorrow, however I need to cut out the catalytic converter. I'm thinking of using a dremel tool, but considering it throws sparks could doing that in anyway lead to me getting blown up?

EDIT: Also Does anyone know the correct Diameter to use for a straight pipe?

[This message has been edited by jasedude (edited 02-21-2010).]

quote Originally posted by ltlfrari: My 88 has twin cutouts but only a single exhaust. The PO simple put a dummy exhaust tip under there clamped to the bodywork. Looks fine and who's to know!

That's just wrong!

quote Originally posted by jasedude: Well then, it seems like I made the right decision in nabbing the exhaust system. My dad thought I was crazy, insisting that the single exhaust system already on my car was perfectly fine. Which is more or less true...but it doesn't look as cool in my opinion. I'm going to do the swap tomorrow, however I need to cut out the catalytic converter. I'm thinking of using a dremel tool, but considering it throws sparks could doing that in anyway lead to me getting blown up? EDIT: Also Does anyone know the correct Diameter to use for a straight pipe?

Using a dremel to cut an exhaust won't blow you up. What it will do is cause you to die of boredom before you get an appreciable amount of cutting done.

A Sawzall would do the job nicely, or you could use the chain-type pipe cutters available at your local auto parts store, which work a bit slower than a Sawzall but faster than a dremel. Chain type cutters look like this:

[This message has been edited by KurtAKX (edited 02-22-2010).]

quote Originally posted by Patrick: That's just wrong!

Yeah, but if I didn't tell you, would you know?

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Dave

www.ltlfrari.com

quote Originally posted by KurtAKX: Using a dremel to cut an exhaust won't blow you up. What it will do is cause you to die of boredom before you get an appreciable amount of cutting done. A Sawzall would do the job nicely, or you could use the chain-type pipe cutters available at your local auto parts store, which work a bit slower than a Sawzall but faster than a dremel. Chain type cutters look like this:

AutoZone carries these tail pipe cutters, were $45.00 to rent. Get your money back when ya return the cutter. They work good and fast. Makes a clean cut on the pipe too!!

quote Originally posted by ltlfrari: Yeah, but if I didn't tell you, would you know?

For sure. There wouldn't be a whole lot of steam coming out of the "dummy" tailpipe at startup.

Seriously though, a duke with two sets of tailpipes sounds different better than a duke with a single set. I noticed that right away when I put the V6 exhaust on my '84 duke.

Ok, Ive hit a bit of a snag. I got the old pipe off and positioned the new exhaust roughly where it should be. However, I noticed that the brackets holding the springs for the muffler don't seem to be made for the v6 muffler. Are the v6 Brackets different then the duke's? I didn't think to get them from the junkyard, if this is the case is there a way to rig something? I'm Itching to test drive this thing :-D

quote Originally posted by jasedude: I noticed that the brackets holding the springs for the muffler don't seem to be made for the v6 muffler. Are the v6 Brackets different then the duke's?

I actually had to cut the spring hanger off the cradle on the passenger side of the muffler as it was interfering with the positioning of the muffler. I believe this hanger (which was welded to the cradle) was hitting the pipe coming out of the muffler for the passenger side tailpipe which of course the original exhaust system didn't have. The spring hanger on the driver's side was fine, and I proceeded to re-attach those three springs.

I then added regular exhaust hangers on both sides that clamped onto the tailpipes immediately in front of where the twin tips converge, and the straps were bolted straight up to the sheet metal mounts for the steel bumper. (Sorry, I don't have a picture of this.) I had my rear bumper cover off while mounting the exhaust so it gave me good access. I like having the exhaust hangers located where I've indicated as this allows excellent control of the distance between the tailpipes and the cutouts in the bumper on both sides.

[EDIT] I should clarify that I did not use any "factory" hangers on the tailpipes, just the two generic hangers by the bumper cutouts, plus all the supporting springs of the exhaust system (minus the ones on the passenger side of the muffler).

[This message has been edited by Patrick (edited 02-24-2010).]

Well, I finally got it all hooked back up, and because my dad is more patient then me, he managed to get it hooked up using both the left and right hand muffler brackets, but boy are those springs a pain! Unfortunately, after we backed it out of the stall we noticed the exhaust pipes are not at all centered, as both tail pipes are to far to the left by about 2 inches. Is this because I used the old mounts for the muffler?

This might be obvious, but connect up the springs BEFORE you connect it to the engine. You need the extra movement of the exhaust to allow you to slide the springs on more easily.

quote Originally posted by jasedude: ...after we backed it out of the stall we noticed the exhaust pipes are not at all centered, as both tail pipes are to far to the left by about 2 inches. Is this because I used the old mounts for the muffler?

I have no idea if you read my previous post or not, but...

quote Originally posted by Patrick: I actually had to cut the spring hanger off the cradle on the passenger side of the muffler as it was interfering with the positioning of the muffler. I believe this hanger (which was welded to the cradle) was hitting the pipe coming out of the muffler for the passenger side tailpipe which of course the original exhaust system didn't have. The spring hanger on the driver's side was fine, and I proceeded to re-attach those three springs. I then added regular exhaust hangers on both sides that clamped onto the tailpipes immediately in front of where the twin tips converge, and the straps were bolted straight up to the sheet metal mounts for the steel bumper. (Sorry, I don't have a picture of this.) I had my rear bumper cover off while mounting the exhaust so it gave me good access. I like having the exhaust hangers located where I've indicated as this allows excellent control of the distance between the tailpipes and the cutouts in the bumper on both sides. [EDIT] I should clarify that I did not use any "factory" hangers on the tailpipes, just the two generic hangers by the bumper cutouts, plus all the supporting springs of the exhaust system (minus the ones on the passenger side of the muffler).

quote Originally posted by Blacktree: I thought this was common knowledge, but apparently was mistaken. Some models of 4cyl Fiero (like the SE) came with the dual-outlet muffler from the factory. The only difference between the single and dual outlet mufflers is the presence or absence of the second outlet pipe. In other words, the V6 cat-back exhaust is "plug-n-play" in the 4cyl exhaust system (no cutting necessary, if the parts are in good condition). Your only concern is whether or not your rear fascia has the cut-out for the second exhaust outlet.

I made a similar post but we are both wrong. You do have to cut no matter how good the parts are. The V6 exhaust separates on the driver's side and the 4-cylinder separates closer to the center of the car. They both, however, have the same straight piece that runs between the front cradle mounts. This is where your catalitic converter is (or isn't). This is where the two systems are commonly joined, as shown in the picture above.

Jonathan