#1  
Old 08-01-2022, 10:44 AM
Tarl Tarl is offline
Senior Member
 
Join Date: Apr 2001
Location: Bsoton, MA
Posts: 120
Default 1968 firebird convertible 400 exhaust including tips

Hi,

The exhaust the PO put on my 68 firebird is horrid, looking to put in a TKX this winter so I might as well replace the exhaust.

I have a pypes x-pipe system with the long dynomax turbo 17749 mufflers on my 66 lemans and I love the sound (been on for 20 years).

Would really like something similar on my 68 firebird with long branch manifolds. I am leaning towards a an 2.5" x-pipe system with transverse muffler. (I realize I will have to modify the convertible brace).

Part of me just thinks I should get the pypes SGF70 x-pipe exhaust and their race pro muffler and be done with it.

But since I really like the dynomax's on my lemans I was wondering if the dynomax 17553 crossover muffler with some generic x-pipe system would be a better fit for me, someone showed me a generic Jegs exhaust system (289-89021) but it wasn't an x-pipe. People have any opinions on the race-pro versus the dynomax?

Finally, I know it's not factory, but I love splitters. I think the repro ones from ames won't work because of the 2.5" exhaust, Has anyone fit the pypes 2.5" (EVT10) exhaust splitters for the 76+ TA onto their first gen?

Appreciate the input!

__________________
1966 Lemans convertible 455/5spd
1968 Firebird convertible 400/4spd
Need more Pontiacs!
  #2  
Old 08-01-2022, 11:46 AM
amcmike's Avatar
amcmike amcmike is offline
Ultimate Warrior
 
Join Date: Oct 2004
Posts: 1,727
Default

Not sure I'm understanding how you plan to use the dynomax muffler? Are you talking about using one in where the muffler sits in front of the tank, like the pypes SGF70?

The dynomax 17553 is meant to be used like an X-pipe. That means both inlets on same side of the muffler. I'm not sure it's going to work if you tried to use it in a cross-flow. If the inlets were on opposite sides of the muffler, part of the exhaust pulse would try to go back upstream on the opposite bank.


Pypes Crossflow has both pipes going through same muffler body, but they do not directly intermix:
Attached Thumbnails
Click image for larger version

Name:	2022-08-01_11h45_28.jpg
Views:	11
Size:	52.7 KB
ID:	595513  

__________________
"The Mustang's front end is problematic... get yourself a Firebird." - Red Forman
  #3  
Old 08-01-2022, 12:25 PM
Tarl Tarl is offline
Senior Member
 
Join Date: Apr 2001
Location: Bsoton, MA
Posts: 120
Default

Good catch! I assumed that was a transverse muffler, but now knowing that it isn't, I looked at Dynomax's catalog and it seems they don't make a transverse muffler for first gen f-bodies, at least one they sell separately (its with that jegs kit I linked without the x-pipe). Looks like I will end up sticking with the race-pro one.

__________________
1966 Lemans convertible 455/5spd
1968 Firebird convertible 400/4spd
Need more Pontiacs!
  #4  
Old 08-01-2022, 02:49 PM
amcmike's Avatar
amcmike amcmike is offline
Ultimate Warrior
 
Join Date: Oct 2004
Posts: 1,727
Default

The 17739 is a single in/dual out that fits the 2nd gen. But really meant for a y-pipe to single tube exhaust then dual outlets.

__________________
"The Mustang's front end is problematic... get yourself a Firebird." - Red Forman
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 08:29 PM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017