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Will Exhaust Help?

  • Thread starter Thread starter Auto Reverse
  • Start date Start date Apr 1, 2005

Auto Reverse

Member
Jul 22, 2003
265
8
19
Buffalo, NY
Apr 1, 2005
#1
  • Apr 1, 2005
  • #1
I have 1 5/8" longtubes and a Flowmaster Force II catback exhaust. I'm trying to squeeze out some more power. What kind of RWHP gains do you guys think I might see if I change out my exisitng exhaust to 1 3/4" longtubes and a MAC 3" catback exhaust?

Thanks for the help!
 

Auto Reverse

Member
Jul 22, 2003
265
8
19
Buffalo, NY
Apr 1, 2005
#2
  • Apr 1, 2005
  • #2
I'm thinking maybe 15 RWHP...is that too optimistic?
 

bluevenom867

I will have images of molesting stuffed animals in
Dec 15, 2003
1,704
1
0
St.Petersburg,FL
Apr 1, 2005
#3
  • Apr 1, 2005
  • #3
I wouldnt,you got the right size for your motor.
 
9

95Mustang302

Member
Mar 30, 2005
302
0
16
Apr 1, 2005
#4
  • Apr 1, 2005
  • #4
if you decide to do that, I'd like to buy your long tubes!

Derek
 

Auto Reverse

Member
Jul 22, 2003
265
8
19
Buffalo, NY
Apr 1, 2005
#5
  • Apr 1, 2005
  • #5
bluevenom867 said:
I wouldnt,you got the right size for your motor.
Click to expand...

I'm pretty sure you're talking about the headers...but what about the 3" MAC catback exhaust, surely the technology improvements would justify the swap. I've heard the MAC catback systems help the car breath a lot better.
 
F

fivespeedfox

New Member
Dec 6, 2004
3
0
0
Apr 1, 2005
#6
  • Apr 1, 2005
  • #6
I think you would lose a lot of midrange torque by going to 3 in. exhaust.

1 3/4 primaries and 3 in. pipes are designed more for 351 applications.

my .02
 

ninety15.0

New Member
Mar 10, 2004
1,336
0
0
Apr 1, 2005
#7
  • Apr 1, 2005
  • #7
Sounds like overkill to me too...i also think you would see a small loss in low end torque. I have heard that a 2.5 inch cat back will support up to 400 horse. What do u have for a mid pipe?
 

Saleen8786

New Member
Oct 7, 2003
209
0
0
Marlton, NJ
Apr 1, 2005
#8
  • Apr 1, 2005
  • #8
since you got the longtubes you might as well get an o/r h or x pipe (dont forget you have 4 cats ) I'd get some gears to
 
B

bLoWn331Cobra

New Member
Apr 1, 2005
6
0
0
Apr 1, 2005
#9
  • Apr 1, 2005
  • #9
3" is too much for your car, i have a blown 331 an my cat back is a 2 1/2 " ... I run bkk long tube to a dr.gas 3" x pipe off road to a spintech sportsman series 2 1/2 cat back.. Low end to top end pulls nice cars sounds killer .. Your good man
 

Auto Reverse

Member
Jul 22, 2003
265
8
19
Buffalo, NY
Apr 1, 2005
#10
  • Apr 1, 2005
  • #10
I have a ProChamber...what are cat's...?

Thanks for the help, I guess is sounds like I'm wasting my money if I go to 3" exhaust.

Do you guys at least think I'll benefit by upgrading from the Force II's to the MAC 2.5" catback system?

I also plan on a 150 shot in the late summer...I'm hoping for at least 425 RWHP, which I can't see the car not making. I just wanted to make sure there wasn't any more power to be made with a better exhaust setup.

Thanks again.
 

bluevenom867

I will have images of molesting stuffed animals in
Dec 15, 2003
1,704
1
0
St.Petersburg,FL
Apr 1, 2005
#11
  • Apr 1, 2005
  • #11
You would able to optimise your cam a little better thou.
 
B

bLoWn331Cobra

New Member
Apr 1, 2005
6
0
0
Apr 1, 2005
#12
  • Apr 1, 2005
  • #12
should have gone with the 185's instead of the 165's ! Thats one problem, other then that ur good.. you'll reach ur number without a problem with 150 shot, which is alot but not a problem
 

Auto Reverse

Member
Jul 22, 2003
265
8
19
Buffalo, NY
Apr 3, 2005
#13
  • Apr 3, 2005
  • #13
Yeah...when I got the AFR 165's I had a stock bottom end.

When the new bottom end was needed I opted for a 331 Stroker, as it was only a few hundred bucks more. How much will I realistically gain if I swapped heads?
 
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