V8 Supra Builder

iTrader: (37)

I'm pulling the rearmount turbo from my TA to make it a DD. I'll have to buy a muffler & tailpipes among other things. My desire like some I've read here is to be quiet but not restrictive, and no droning at highway speeds- I had a Flowmaster on my truck & got rid of it for that reason. My setup is:
A 383 with LT4 heads & intake, Hot cam, 52mm TB, 1.6 roller rockers, Mac mid-length headers, high flow aftermarket cat, and a 3" intermediate pipe.

The pipe had a header flange to mount the turbo, so I can easily use a collector adapter to mount either a 3" or 2.5" inlet muffler and have no need for a catback system. I have a 3" adapter, so since I have a modded motor I'm leaning towards a 3" inlet muffler. I want to retain the stock look and am planning to pickup some stock exhaust tips, or something with a larger inlet that has the same appearance. This is also a budget build, I'm selling the other parts to pay for what I'm buying.

The OEM replacement mufflers are 24" overall with a 19" case.

Here's a stock LT1 exhaust sound clip I found:
I've been doing some reading & searching on YouTube and so far have eliminated the following due to sound and/or cost/quality:

• Magnaflow (and the similar Jones/AP Xlerator, a shame because a SS crossflow muffler was only $50)
• Flowmaster & the similar Jones/AP model
• Dynomax Ultraflow
• Pypes
• All race/bullet mufflers
• Hooker Aerochamber (have read about quality issues)
• Dynomax VT (interesting idea that apparently does not hold up)
• Borla (too expensive)

I'm leaning toward the Dynomax Super Turbo. I see it is a 2.5" in/out for #17739 (OEM sized case) and the larger one is 3" in/out #17670. The 17670 is a little wider at 26" & 22" (the case is fatter also) and shows as being for the LSx F-bodies but I'm sure it could be adapted. There is a third one #17786 that is 2.5" in and 2.25" out, 26" OA and 21" case. The 17739 is the best deal of the lot at a little over $60. Dynomax describes the ST as the quietest performance muffler they sell.

This video has an LT1 Corvette with Super Turbo mufflers. I like the sound, but I know the system is different:

Other options include:

• Flowtech's Afterburner 50363FLT ($65), 3" in and 2.5 out. I watched a couple of videos:
  LT1 with Flowtech Afterburner - YouTube
  
  and
  
  
  94 Trans Am with Flowtech Afterburner Soundvid. - YouTube
  
  It did not sound too bad, especially since it is a short (14") case muffler. It has good reviews from F-body owners.

The Walker stock replacement units:

• Sound FX 18375 ($35). I found a video with a third gen Camaro and it sounded crappy IMO.
• Quiet Flow 22354 (SS, $75), both are OEM size and have 2.5" in and 2.25" out. The latter being a "premium" muffler carries a lifetime warranty and a money back replacement with up to $50 in labor. I'm thinking these would be too restrictive.

The drawbacks I see to a full 3" in/out system are:

• Noise
• Added cost for 3" tailpipes and/or adapters (the adapters applies to all the 2.5" outlet mufflers also)

If I can find a sound clip of the Super turbo 17670 3" in/out this would be a help.

Vicious95Z28

iTrader: (1)

You don't leave many options but I like Spintech.

SwampWS6

iTrader: (7)

I'd say the best way to judge off sound is to hear the setups in person. Someone with a killer exhaust setup with a shitty quality camera/phone takes away a lot of choosing an great throaty exhaust. So hear them in person before spending $$$$. Good luck!

V8 Supra Builder

iTrader: (37)

Visited their site. Difficult to use IMO, they offer a lot of mufflers. As near as I can tell (lack of illustrations), the crossflow would be the one for an F-Body, but they are like $170. I saw their dual outlet tips are $155 each! Both are way too much for my budget.

I don't get out much and am in a small town. While that's a great idea it is not practical for me.

V8 Supra Builder

iTrader: (37)

After doing a lot of shopping, it looks like I can score the 17670 3" I/O Super turbo, two stock 2.25" tailpipes, and 6 clamps @ Advance for about $101 thanks to a $10 coupon & 20% off plus 7% cashback (offsets the sales tax). It's rare when their prices beat those online, and factoring in returns are a lot easier I'll buy there. I found a couple of 3" x 2.25" reducers and 2.25" dual pencil exhaust tips for about $76, so I'm around $177 for all new parts.

chaney1974

My phone isn't letting me upload my video but I have Spintech muffler and it is truly bad ***! YouTube it Spintech F-body.

V8 Supra Builder

iTrader: (37)

As an update, I had no idea how difficult it would be to find a pair of 3" OD x 2.25" ID reducers. Walker/Dynomax doesn't make one, and the vendors that do apparently don't make many. The only parts house that carries them is O'Reilly, and while they only want $4.50 each, they want over $18 to ship them. I'm looking at buying some aluminum and making 3/8" wall bushings since the muffler is wider than stock.

UPDATE
I found a pair of 3" x 3/8" wall aluminum pipe sections (2.25" ID) on eBay that were 1.25" wide for $6. I cut a diagonal slot in each so they would seal the 2.25" pipe better and they are a good fit.

UPDATE 2
Sound clip attached. I've only driven the car for a short period and with the window open, but I think the Dynomax 17670 is the best bang for the buck w/o being excessively loud.