Georgia Fiero Club Forum

All Things Fiero => Tech Tips, Tech Questions => Topic started by: f85gtron on March 05, 2018, 07:04:53 am

Title: Which muffler? Thrush or Spintech for 3800sc?
Post by: f85gtron on March 05, 2018, 07:04:53 am
I have acquired both thrush and Spintech mufflers that I can use for my 3800sc exhaust. Which one sounds better? I looked for a comparison, but couldn't find this specific comparison. I'm gonna run a cat too. I'm going for something mellow, less drone potential at highway speeds. Some loudness is ok when i punch it.
Also, any tips recommendations?
Ron

Ps. I forgot to mention they're both 1 in, 2 out.
Title: Re: Which muffler? Thrush or Spintech for 3800sc?
Post by: GTRS Fiero on March 05, 2018, 07:10:55 am
Nothing like a 3800SC, but I have a Spintech on my 3.4.  I get what I call harmonics at highway speeds.  Actually, certain RPMs.  I don't know if the muffler causes this or not.
Title: Re: Which muffler? Thrush or Spintech for 3800sc?
Post by: Fierofool on March 05, 2018, 07:58:37 am
Oftentimes harmonics are caused by something nearby reacting with your exhaust.  I find that happens when near trucks or other vehicles with exhausts that have a little tone to them. 

Ron, since you're using a 3800, look around in the yards for some Grand Prix exhaust tips. 
Title: Re: Which muffler? Thrush or Spintech for 3800sc?
Post by: GTRS Fiero on April 07, 2018, 12:44:44 pm
I have C4 tips on mine.  The exhaust shop did a terrible job.  For the harmonics, I don't recall being near anyone, but certainly no big trucks.  If I speed up or slow down a few MPH, the sound goes away.  It sounds almost like tire whine, but is metallic.  Maybe some of the exhaust is rubbing against something.

For me, the Spintech is mellow, but has plenty of throatiness.  I'm curious what Raydar thinks.  I think he was the one that went through several mufflers on his 4.9.