• 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
lets talk 3'' exhaust and bigblocks...
#1
Ive been driving my 72 for a year now with mufflers bolted to my long tube headers and its time to finish the rest of my exhaust. Now from everything ive ever read and or heard most guys I know who are running 429/460+ strokers are running 3" exhaust but there also in jacked up mud trucks with tons of room to do anything they want with it. Us on the other hand, dont. Ive called two shops in my area and no one wants to bend 3" and just reccomend ordering pre fit exhaust.

Im almost ready to give in and just go 2.5"--- But with my 532 I think Id rather have the 3" Smile

I did some searching and didnt find much for a 3" exhaust kit for our 71-73 mustangs. SO any one got the big pipes? Im curious to see some pics hopefully of 3" and some feedback from those who have it... Thanks guys

Cody--
72 Mach-1 12:1 532 Forged internal Scat stroker, Kaase P51 heads, Comp roller cam, March serpentine conversion, C6 manual VB, 9'' 4:33:1.
66 convertible 289, 82k miles.
  Reply
#2
Not sure the size of mine. I can measure tomorrow or something. I want to say 2.5", but they look pretty damn beefy:

[Image: jj8pqa.jpg]

By the way, it's a 429.

Steve



[Image: 25yvyp3.jpg]
  Reply
#3
Here is what we ended up with. Very unique sound with the mufflers at the rear.
   

Mitch
  Reply
#4
i have 3 inch exhaust headpipes and 2.5 tail pipes with my 460. however, my exhaust head pipes hit the frame. i need to take my car to the exhaust shop and have them dent the area of hitting.

i'm also going to ditch the tail pipes going over the axle and just exit infront of the rear tire (i'm going to have to cover up the fuel lines with heat tape).

however, some guys go 3 inch tail pipes but go under the axle instead of over it.

  Reply
#5
Here is my 3". Not finished past the axle yet.

[Image: 73mach-exhaust4.jpg]

[Image: 73mach-exhaust8.jpg]

[Image: 73mach-exhaust9.jpg]

1965 D Code
[Image: 64-dcode-200x83.jpg]
  Reply
#6
Awesome pics guys. I'd like to do 3" all the way back with an x pipe. Well see what happens. Anyway we could get a sound clip vintage? Basically that's a similar set up as the 05+ mustangs with the muff right at the tail end. Very cool. Still some one well chime in with a kit. Looked at summit racing and they have universal sets of 3" with lots of curves and turns for 250 bucks. Kinda leaning that way...

Cody--
72 Mach-1 12:1 532 Forged internal Scat stroker, Kaase P51 heads, Comp roller cam, March serpentine conversion, C6 manual VB, 9'' 4:33:1.
66 convertible 289, 82k miles.
  Reply
#7
I ran a custom exhaust shop for many years and have done my own exhaust since I was able to buy my first beer!
No offense to the 3" exhaust guys out there, but there really is no performance advantage to running the 3" as opposed to 2.5" unless you are pushing 600hp and you just want all out top end. There may even be a disadvantage due to the lack of backpressure. Exhaust flows just like water through a pipe, so the larger the pipe, the more free your exhaust will flow right? Well to a point, you need a little bit of restriction to help keep the pressure up and the air flowing smoothly.
If you just want it really loud and you are not concerned with off the line or low end power and you have a bunch of room, then maybe 3" is the way to go. But for everyday running, clearance and performance, unless you have a diesel, in my experience 2.5" is a more then sufficient to get the job done, and maybe even be better.




  Reply
#8
In one of the engine builder competitions from a few years ago, there was an FORD engine builder that had to switch from a big pipe to a smaller pipe header and was amazed that he actually increase his power/torque with the smaller pipe.

It was in something like Car Craft, or HOT ROD or something like that. Might want to do some searching.

[Image: 11jmcuc.png]
351C Bold Manners, Brash Attitude
Favorite Teams: Michigan Wolverines and Whoever Is Playing Ohio State.

When I drive past a herd of cows, the cows MOO at me
  Reply
#9
guys72Mach1;63157 Wrote:I ran a custom exhaust shop for many years and have done my own exhaust since I was able to buy my first beer!
No offense to the 3" exhaust guys out there, but there really is no performance advantage to running the 3" as opposed to 2.5" unless you are pushing 600hp and you just want all out top end. There may even be a disadvantage due to the lack of backpressure. Exhaust flows just like water through a pipe, so the larger the pipe, the more free your exhaust will flow right? Well to a point, you need a little bit of restriction to help keep the pressure up and the air flowing smoothly.
If you just want it really loud and you are not concerned with off the line or low end power and you have a bunch of room, then maybe 3" is the way to go. But for everyday running, clearance and performance, unless you have a diesel, in my experience 2.5" is a more then sufficient to get the job done, and maybe even be better.

well my motor just dyno'd at 627hp and 640lbs of tq and revs to 7000rpms. i think i need the 3 inch, but,,,,,,,,,,,,,,,,,,,,,,,,i'm running 2.5 tails.
  Reply
#10
xoliex;63165 Wrote:
guys72Mach1;63157 Wrote:I ran a custom exhaust shop for many years and have done my own exhaust since I was able to buy my first beer!
No offense to the 3" exhaust guys out there, but there really is no performance advantage to running the 3" as opposed to 2.5" unless you are pushing 600hp and you just want all out top end. There may even be a disadvantage due to the lack of backpressure. Exhaust flows just like water through a pipe, so the larger the pipe, the more free your exhaust will flow right? Well to a point, you need a little bit of restriction to help keep the pressure up and the air flowing smoothly.
If you just want it really loud and you are not concerned with off the line or low end power and you have a bunch of room, then maybe 3" is the way to go. But for everyday running, clearance and performance, unless you have a diesel, in my experience 2.5" is a more then sufficient to get the job done, and maybe even be better.

well my motor just dyno'd at 627hp and 640lbs of tq and revs to 7000rpms. i think i need the 3 inch, but,,,,,,,,,,,,,,,,,,,,,,,,i'm running 2.5 tails.

Nice and very respectable!..I was being conservative in that hp range though. There is a calculation to it, back pressure vs flow or something of the sort and I think the border where it breaks is closer to 800-900hp. Maybe do some research on it, like Wolverine suggested. I am sure that Hot Rod or some published mag has worked it all out.
VintageUpgrades;63122 Wrote:Here is what we ended up with. Very unique sound with the mufflers at the rear.

Dude, that thing is sick! Very nice frame work.




  Reply
Share Thread:  


Possibly Related Threads...
Thread Author Replies Views Last Post
  2 1/2 "Exhaust Cainsable 11 352 6 hours ago
Last Post: NOT A T5
  Can FMX be removed from car without dismounting exhaust? Spechti 4 300 05-11-2018, 11:12 AM
Last Post: Spechti
  Head and Exhaust Confusion digithead 14 469 04-20-2018, 07:47 AM
Last Post: Hemikiller
  Exhaust System Kits and other questions scgamecock 6 357 03-28-2018, 04:00 PM
Last Post: red351
  1973 351C 4V Exhaust Manifold Photos Needed Wolverine 2 485 02-26-2018, 08:45 AM
Last Post: OMS
  Exhaust Recommendations RadRacer203 15 1,009 01-27-2018, 04:25 PM
Last Post: goodnigh
  Dual Exhaust Kits - what fits? roadwarrior 10 1,146 01-02-2018, 12:04 PM
Last Post: roadwarrior
  ‘73 Vert. Dual Exhaust install Pastel Blue 5 961 12-19-2017, 08:11 AM
Last Post: imusa76



Users browsing this thread: 1 Guest(s)