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Magnaflow Cat Back install problems...

  • Thread starter Thread starter gmags
  • Start date Start date May 27, 2004
G

gmags

New Member
Feb 25, 2002
44
0
0
toms river NJ
May 27, 2004
#1
  • May 27, 2004
  • #1
i installed a stainless Magnaflow cat back on my 88 GT. I can't get a good seal where the pipes attach to the stock H pipe! I've tried re-tightening the nuts several times, but i still have some small leaks there. Anyone else have a problem like this? The kit is my opinion is difficult to install, (3 pipes and a muffler per side), i wish i had went with Flows! I've installed 2 flowmaster cat backs w/o any problems like this...
 

TwinTurbo93

Founding Member
Jan 19, 2002
153
0
0
Orlando
May 27, 2004
#2
  • May 27, 2004
  • #2
I have never had a problem with a ball-and-socket type flange on any exhaust... if you need to have the flowtubes and everything else welded up, take it to an exhaust shop to get that done and see if it helps, they should be able to get rid of it for you, more than likely its the u-bolt clamps leaking, not the flange, or maybe the flow tubes don't align correctly with the h-pipe?
 
G

gmags

New Member
Feb 25, 2002
44
0
0
toms river NJ
May 27, 2004
#3
  • May 27, 2004
  • #3
i did have a heck of time getting each side totally lined up and hung! compared to a flowmaster system, this one was difficult to install...it took me more than 5 hours! granted i was working in my driveway, but it's nothing i haven't done before. i also never had a problem with the ball/socket connection at the end of the H pipe (both stock and off road). I'm dead set against welding the H pipe to anything! i'd buy a flowmaster system before that. this paticular car still had a ford factory exhaust system on it before this. i wish i never installed the magnaflow system! i definately will not reccomend magnaflow to anyone. it's too late to revert back now 'cuz i had to cut the factory exhaust off..
 
T

TattooMatt

New Member
Mar 23, 2004
72
0
0
GA
May 27, 2004
#4
  • May 27, 2004
  • #4
gmags said:
i installed a stainless Magnaflow cat back on my 88 GT. I can't get a good seal where the pipes attach to the stock H pipe! I've tried re-tightening the nuts several times, but i still have some small leaks there. Anyone else have a problem like this? The kit is my opinion is difficult to install, (3 pipes and a muffler per side), i wish i had went with Flows! I've installed 2 flowmaster cat backs w/o any problems like this...
Click to expand...
I installed one too. I had to have the flow tubes shortened a tad. No biggie. I took it to a muffler shop after I installed it and they welded it and adjusted everything for about 50bucks. No leaks!
 

MahFiVeOh

Founding Member
Apr 26, 2002
531
9
49
Ontario, Canada
May 27, 2004
#5
  • May 27, 2004
  • #5
No probs with mine
 
G

gmags

New Member
Feb 25, 2002
44
0
0
toms river NJ
May 27, 2004
#6
  • May 27, 2004
  • #6
i was just under the car and i think i see what my problem is...
the two flanges are actually touching, preventing the complete seal. i must admit that the magnaflow flange is super thick! i'll probably break the studs before i get the whole thing tight. i guess my next step will be to wrestle the pipe off, and try to grind the edges of the flange down a bit where they are touching, and then see if i can get a good seal. the leaks are minor, but i know that they are there! i can feel the exhaust escaping there. i really only hear the leaks when its completly cold, or like when you go to the fast food drive thru where the sound can bounce back off the building...
 

TIMMY2734

Founding Member
May 17, 2002
1,330
1
36
Queens, NY
May 27, 2004
#7
  • May 27, 2004
  • #7
mine fit fine and is leak free for about 2 years. Took about an hour TOPS to put it in
 
G

gmags

New Member
Feb 25, 2002
44
0
0
toms river NJ
May 29, 2004
#8
  • May 29, 2004
  • #8
while wrestling with the flow tubes yesterday in the driveway, it started pouring down rain. i didn't have them off yet, so i bit the bullet and took the car to my favorite meinike in bricktown. they cut the flanges off, and put some different ones on (cost me $60).....no leaks! sounds great now! not much louder than stock at idle, nice & loud when i get on it...
 
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