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91 Exhaust System

  • Thread starter Thread starter NFLjunkeez
  • Start date Start date Jul 8, 2014
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NFLjunkeez

Member
Feb 16, 2013
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0
7
Jul 8, 2014
#1
  • Jul 8, 2014
  • #1
I had an exhaust pipe break about 2 feet in front of a muffler due to rust. When I looked under the car, that 2 foot pipe (coming out of the muffler) is dangling towards the engine just waiting to catch something causing it to do a "pole vault" action and can cause big damage, possibly to my gas tank as the muffler rips away and bounces around under the car.

As some of May know, I've been battling an overeating issue with my 91 5.0 for a long time. My current exhaust pipes are 2".

Now that I have to replace these pipes, should i increase the size to 2.5 or 3" pipes? Would that help get heat out of my engine? What would it do to my back pressure?

I want to upgrade for better performance while at the same time getting rid of the amount of heat that is staying in my engine.

It's not overheating anymore but it still runs hot. After upgrading to A Frame gauges, my temp gauge reads just above 250° and stays there.

Would increasing my pipes help lower the temp?
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
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gainesville
Jul 8, 2014
#2
  • Jul 8, 2014
  • #2
No reason not to go 2.5". You won't regret it.
 
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84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
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South Jersey
Jul 8, 2014
#3
  • Jul 8, 2014
  • #3
Stock exhaust should be 2.25". The upgrade that most go to will be 2.5" exhaust and I agree that this is where you should be moving forward. There is also no reason why your car should be running that hot, the exhaust should have no bearing on that either way
 
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N

NFLjunkeez

Member
Feb 16, 2013
30
0
7
Jul 9, 2014
#4
  • Jul 9, 2014
  • #4
84Ttop said:
Stock exhaust should be 2.25". The upgrade that most go to will be 2.5" exhaust and I agree that this is where you should be moving forward. There is also no reason why your car should be running that hot, the exhaust should have no bearing on that either way
Click to expand...

What is the purpose of the upgrade? Does a quarter of an inch make that much of a difference?
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
5,222
3,254
204
South Jersey
Jul 9, 2014
#5
  • Jul 9, 2014
  • #5
NFLjunkeez said:
What is the purpose of the upgrade? Does a quarter of an inch make that much of a difference?
Click to expand...
2.5" exhaust is more of the industry standard than anything else. Is it absolutely needed? No. In years past I have had a low 10 second fox body that made roughly 500hp and still used 2.25" mufflers. That being said, any of the aftermarket exhaust systems that you will see in today's market will be 2.5". My vote for a car like yours would be a cat back exhaust system from a company such a magnaflow, stainless steel construction and a life time warranty. If it was some more growl that you are after at the same time then you can upgrade the stock H pipe to either an aftermarket H or X pipe with high flow cats.
 
Reactions: NFLjunkeez

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Jul 9, 2014
#6
  • Jul 9, 2014
  • #6
Magnaflow or bassani. Both offer stainless and are very well made. I would avoid Mac, or pypes. They are cheap for a reason.
 
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