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catback 2.5" or 3"?

  • Thread starter Thread starter Holik95
  • Start date Start date Jan 23, 2007
H

Holik95

New Member
Aug 14, 2005
90
0
0
Granite City,IL
Jan 23, 2007
#1
  • Jan 23, 2007
  • #1
i was going to buy a mac catback in a couple weeks but dont know if i should get the 2.5 or 3 inch system. can someone help me choose? is there a power/sound difference between the two?
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Jan 23, 2007
#2
  • Jan 23, 2007
  • #2
Unless you have plans on running a really high boost twin screw (25+psi) in the future I think you're better off with the 2.5 inch. The 3 inch is overkill unless you are passing some serious spent gas. You need to maintain a small amount of back pressure for the engine to run at peak efficiency.

U.M.
 
H

Holik95

New Member
Aug 14, 2005
90
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0
Granite City,IL
Jan 25, 2007
#3
  • Jan 25, 2007
  • #3
ok i'll get the 2.5". what size tips look the best?
 
C

Cobracide

Founding Member
Nov 8, 2001
111
0
0
Charlotte, NC
Jan 25, 2007
#4
  • Jan 25, 2007
  • #4
Holik95 said:
ok i'll get the 2.5". what size tips look the best?
Click to expand...

3" tips fill out the cutouts best.
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Jan 26, 2007
#5
  • Jan 26, 2007
  • #5
I think my Magnaflows have 3.5 in tips. They fill up the bumper cutouts quite well.

You could always go for the 3lb coffee can tips if you really want to impress the ricers. That's what I do when I go out cruising....

U.M.

 

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SVT98Snake

New Member
Apr 15, 2005
258
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0
OK, USA
Jan 26, 2007
#6
  • Jan 26, 2007
  • #6
I gained 2 mph consistently with the MAC 3" over the 2.5 Stinger kit I had. I also noticed a considerable seat-of-the-pants difference top end. I did lose a little down low on torque on the dyno, but it pulls harder up top.

I do have plans for a twin screw though and that is the only reason I got the 3".

But for the record, before the 3" I ran 120, now I run 121.5-122 consistently.

I like the 3.5 tips the best, but my old Borla 4" tips looked sick. If you do go 2.5 though, buy the SLP double wall tips....those are awesome. I even have a brand new unused set if you are interested.
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Jan 26, 2007
#7
  • Jan 26, 2007
  • #7
Wow, you had a complete 2.5 inch system (X-pipe & cat-back) and then swapped it out for a 3 inch system? Both systems utilized the same mid-pipe? Catted? Uncatted?

U.M.
 

SVT98Snake

New Member
Apr 15, 2005
258
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0
OK, USA
Jan 26, 2007
#8
  • Jan 26, 2007
  • #8
sorry...clarification...

2.5 o/r X pipe into a 3 cat back. Prior I had the 2.5 X into the 2.5 Borla...
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Jan 26, 2007
#9
  • Jan 26, 2007
  • #9
SVT98Snake said:
sorry...clarification...

2.5 o/r X pipe into a 3 cat back. Prior I had the 2.5 X into the 2.5 Borla...
Click to expand...
Gotcha! Just wanted to clear that up. I didn't think you were running 3 inch throughout. Hell, does anyone even make a 3 inch X?

U.M.
 

SVT98Snake

New Member
Apr 15, 2005
258
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0
OK, USA
Jan 26, 2007
#10
  • Jan 26, 2007
  • #10
Uncle Meat said:
Gotcha! Just wanted to clear that up. I didn't think you were running 3 inch throughout. Hell, does anyone even make a 3 inch X?

U.M.
Click to expand...

I know Flowmaster did.....I wouldn't recommend it though. Like you said....overkill for the whole kit.
 
C

Cobracide

Founding Member
Nov 8, 2001
111
0
0
Charlotte, NC
Jan 26, 2007
#11
  • Jan 26, 2007
  • #11
Uncle Meat said:
I think my Magnaflows have 3.5 in tips. They fill up the bumper cutouts quite well.

You could always go for the 3lb coffee can tips if you really want to impress the ricers. That's what I do when I go out cruising....

U.M.
Click to expand...

Meat - you are correct, 3.5 tips. Now I have fart can envy now! Do they sound as good as they look? Nice ricer mod. ; )
 
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