I have a fresh 3800 Series II SC ready soon for a swap. Trying to plan ahead, I would like to get some good ideas about exhaust system choices available for this Fiero swap.
There are many threads about the 3800 exhause in th esearch function. there are lots of different ways people route them, too many to list. I like the stock manifolds and use a spintek muffler www.spintek.com call them and tell them what you have and they have the correct muffler for you. Buy a couple of exhaust doughnuts to cut in half for the bends and a couple of straight pipe pieces. it is easy like puzzle.
As Revin has said the choices for a 3800 exhaust are numerous. If you want to keep your trunk then you are more limited in your choices. Spintech, and the Flotech afterburner are about the same size as the stock muffler. Some guys have adapted the Camaro/Firebird Flomaster crossflow but it needs modification to fit. A stock drop in, Fiero size muffler cannot be any longer than about 13" L about 10" H and 4" W. With such a small muffler the sound at the exhaust will be loud. . If you decide to eliminate the trunk then you can use a larger, quieter muffler like the Magnaflow or even dual exhaust mufflers.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
A stock drop in, Fiero size muffler cannot be any longer than about 13" L about 10" H and 4" W. With such a small muffler the sound at the exhaust will be loud. . If you decide to eliminate the trunk then you can use a larger, quieter muffler like the Magnaflow or even dual exhaust mufflers.
Any reason a muffler longer than 13' won't fit? I'm looking at a Spintech muffler that is 15' L, 10' H and 4' W. Link below.
I use a magnaflow #12158 muffler that is a shortened F body muffler that does fit barely with the trunk left intact and works pretty well. As for the exhaust system itself it depends on a lot of things like which tranny you are using as the stock 3800 cross over interferes with the Fiero 4 speed manual shifter assembly. How much power you are planning as more power does require larger diameter piping, if you are running a CAT plus many more things. Dan
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DARN Cars now open with Over 30 years wiring experience between cars and trade as an avionics technician in both Canadian Air Force and civilian aviation. Over 25 years experience building and modifying cars. Over 10 years of full Fiero engine swaps and harnesses building and still going.
Call Spintek. Tell them 3800/Fiero , size of pipe and they will get the correct one for ya. Many have asked for their mufflers and they know where to notch or whatever it is they do, to insure a good fit.
Mine made as I said
[This message has been edited by revin (edited 04-04-2013).]
I'm following a very similar set up to yours. Question is how far below the trunk does your exhaust hang? I have mine mocked up right now and I'm worried how low the muffler would be hanging. Any pictures of it installed would be appreciated.
Spinteck makes a great sounding muffler. I had them on my 05 GTO and my 88 Fiero w/ DOHC 3.4
I plan to do almost the same thing you did, except I am going to use a series of 90's and have it loop around to top of itself. One loop will be the cat, then below it the muffler. The muffler will be horizonal not vertical like in yours. I have a picture of it, but its at home. Its the same "loop on top of a loop" picture that many have used here. I am cutting the trunk out so space is not a problem. Great looking system.
Luke, I am just using the stock manifolds. I had them ceramic coated. If I was doing it again, I'd swap out the front manifold for a Powerlog from ZZP, and use the stock rear one.
no "hangin" pic. sorry the way I mocked it up was starting at the manifold, get that 1st bend right. From there it is just a matter of turning some of the "bends or curves" in difference directions to get the muffler tucked up under the rear. I know it seems like it is flat sitting there but there is a leaning affect once attached to the manifold. not 90* or 45* but somewhere in between. you will see once you get to that point.
I also painted a very high heat paint(black) to help hide the muffler. But you really cannot see it all that well.
[This message has been edited by revin (edited 06-10-2013).]
Call Spintek. Tell them 3800/Fiero , size of pipe and they will get the correct one for ya. Many have asked for their mufflers and they know where to notch or whatever it is they do, to insure a good fit.
Mine made as I said
Revin is that a Cat before your muffler? Does your setup fit without cutting your trunk? I can't believe that will fit without the muffler almost touching the road. Any pictures of it installed on your car that we could see? I want a cheap easy setup to get me through the summer, because next winter I'm gonna go turbo and will have to completely change my exhaust setup.
anyone know the part number for the spintech muffler 2.5"in dual 2.5" out that revin used. I called a while ago and got the price and part number but have seince lost the information. also if there is a way to order off their website using the part nu,mber or even better a link to it.
Here is some pics of my current setup. It is a spintech with a 3 inch inlet and dual 2 1/2 outlets. IMHO it sounds very mellow, there is no rasp to this setup which I am very happy with the way it turned out. I am using ZZP's Stainless headers. There is my first startup video as well. http://youtu.be/Q6Ul2sNg_ZU
Here is some pics of my current setup. It is a spintech with a 3 inch inlet and dual 2 1/2 outlets. IMHO it sounds very mellow, there is no rasp to this setup which I am very happy with the way it turned out. I am using ZZP's Stainless headers. There is my first startup video as well. http://youtu.be/Q6Ul2sNg_ZU
When I bought my 84 with a 3.8 sc, it had WC Fiero headers hooked up to the stock 4 cyl exhaust. The car was real quiet. Last week, I had the 3" single in/ 3" single outlet WC Fiero exhaust system installed. The single in/out setup came with the car and was never installed previously because the PO thought it would be too loud. It uses a Spintek muffler, which I thought might be too noisy. It was a cat delete setup, but I had the muffler shop install it with the 3" ZZP cat that was on the car already. To my delight, the car is not noisy at all, and there is little to no drone at highway speeds. Because it's a 3" pipe, I may get accused of being a bit ricer since the only acceptable stainless tip I could find was somewhat unusual by my taste. It hangs a bit lower than I would like, but that may be due to the installer. I think with a little more patience, it could have been made to fit up tighter, but after all it is 3" and takes up a lot of room under there.
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