hi any one running twin 3 inch exhausts are you running it over or under diff
pics would be great
thanks shane
3 inch exhaust
Started by
_wileyg_
, Aug 06 2009 07:06 PM
30 replies to this topic
#2
Posted 06 August 2009 - 07:12 PM
I highly doubt anyone has managed to fit a 3" exhaust over the diff
#3
Redslur
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Posted 06 August 2009 - 07:22 PM
^^^^ I am with him^^^^^
#4
_cruiza_
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Posted 06 August 2009 - 07:48 PM
Well you would be wrong go directly to jail do not pass go do not collect two hundred dollors
My Hatch with 9in diff and sway bar and 3in exhast over the diff no knocks no rattles fully loaded or empty
(took the guy all day to do from extractor to tail pipe 3in all the way bar the very front twin 4in down to twin 3in then single 3in mandel bent no squashed or kinks
My Hatch with 9in diff and sway bar and 3in exhast over the diff no knocks no rattles fully loaded or empty
(took the guy all day to do from extractor to tail pipe 3in all the way bar the very front twin 4in down to twin 3in then single 3in mandel bent no squashed or kinks
#5
_mumstaxi_
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Posted 06 August 2009 - 07:50 PM
I too have a single 3 inch going over the diff, although the UCs have a larger diff cavity, mine is not lowered and i don't have a big 9 inch 
MT
MT
#6
TerrA LX
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Posted 07 August 2009 - 01:23 AM
Might be just me but is that 3"???
Looks like a kink next to the shock?
The real question is WHY?
#7
Posted 07 August 2009 - 07:57 AM
That's well done Cruiza although I would probably ask the same questions as above, and it depends on the definition of a kink - I wouldn't be happy with bends that tight, did it get very hot?
Also Mumstaxi has a good point, more room in a UC
Also Mumstaxi has a good point, more room in a UC
#8
_mumstaxi_
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Posted 07 August 2009 - 09:18 AM
Might be just me but is that 3"???
Compared to the shockie id say yes 3", I know what you mean tho, 3" does not look that big these days (so my misses was telling me, LOL), i think due to all the spanka's fitting the 4 & 5" Cannons you seem to see on everything !
Sad part is, most of the time they are on N/A 4 cylinder sh1tboxes
Ha-ha !
MT
#9
_sbc57lx_
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Posted 07 August 2009 - 09:39 AM
A little off the topic , from the photos the rotor looks like it is vented ( not solid ) ???.
If so, what are those brakes from, ??
I'm still to have a diff made up , and will be running rear disks, just exploring my options.
If so, what are those brakes from, ??
I'm still to have a diff made up , and will be running rear disks, just exploring my options.
#10
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Posted 07 August 2009 - 12:23 PM
Well there you go! 
I just had my car into the exhaust shop getting a quote on a new exhaust and I am going for a single 3" system to the muffler and 2 1/2 over the diff. His words were you won't get the 3" over the diff. I have a 10 bolt Salisbury though. Even with the 2 1/2 I already have over it, it only just clears things. Would have been a very tight fit with the 3".
I just had my car into the exhaust shop getting a quote on a new exhaust and I am going for a single 3" system to the muffler and 2 1/2 over the diff. His words were you won't get the 3" over the diff. I have a 10 bolt Salisbury though. Even with the 2 1/2 I already have over it, it only just clears things. Would have been a very tight fit with the 3".
#11
myss427
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Posted 07 August 2009 - 01:40 PM
Mines 3 and a half over the diff, but the floor pan is different! You can see it in the garage section.
#12
_LHoon_
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Posted 07 August 2009 - 11:35 PM
I made twin 3 inch in my LC, but went under the diff. I don't see any real disadvantage with going under.
There's some photos in this old thread: http://www.gmh-toran...showtopic=33448
There's some photos in this old thread: http://www.gmh-toran...showtopic=33448
#13
_2wild4u_
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Posted 08 August 2009 - 12:57 AM
yep ,my twin 3 inch goes under the diff no problems
#14
_cruiza_
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Posted 08 August 2009 - 07:12 AM
Yes that is a 3in pipe (just call me a lair why don't you)
The guy that did it for me was Graham Valintine, he did exhasts for a formula one team for a few years, you might say he knew his stuff!
As to the why I had it made up.
A single 3 in pipe flows 15% more then a twin 2 and a half system
If you have ever heard a V8 super car from the late eighties early ninties then you will know what my car sounds like, low revs rumble high rev high pitched scream
Burnout
the burnout isnt the best, but i had never done one before, at the end you can really get to hear why I liked it so much
The guy that did it for me was Graham Valintine, he did exhasts for a formula one team for a few years, you might say he knew his stuff!
As to the why I had it made up.
A single 3 in pipe flows 15% more then a twin 2 and a half system
If you have ever heard a V8 super car from the late eighties early ninties then you will know what my car sounds like, low revs rumble high rev high pitched scream
Burnout
the burnout isnt the best, but i had never done one before, at the end you can really get to hear why I liked it so much
#15
ls2lxhatch
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Posted 08 August 2009 - 02:35 PM
The area of a 2.5" pipe is 4.9" and the area of a 3" pipe is 7". The dual 2.5" system has area of 9.8" vs the single 3.0" system area of 7". Therefore the dual 2.5" system has 40% larger area than the 3" system. It is difficult to believe that the 3.0" system can flow 15% more than a system with 40% more area. I would like to see some flow bench results.
There are advantages and disadvantages in running under the diff. What is a disadvantage to me may be a advantage to others as we all have different aesthetic and performance criteria.
1. Under the diff will flow better due to the shorter pipe with less bends but it will also be louder.
2. Clearance for decoupled sway bar mounts can be a problem with under the diff.
3. Clearance at full suspension travel or when the car is on a chassis hoist can be a problem.
The tailpipes on my hatch ran under the diff and I would not do it again if I avoid it.
There are advantages and disadvantages in running under the diff. What is a disadvantage to me may be a advantage to others as we all have different aesthetic and performance criteria.
1. Under the diff will flow better due to the shorter pipe with less bends but it will also be louder.
2. Clearance for decoupled sway bar mounts can be a problem with under the diff.
3. Clearance at full suspension travel or when the car is on a chassis hoist can be a problem.
The tailpipes on my hatch ran under the diff and I would not do it again if I avoid it.
Edited by ls2lxhatch, 08 August 2009 - 02:38 PM.
#16
_Bomber Watson_
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Posted 08 August 2009 - 03:14 PM
Cruisa, i'll have to teach you how to do a skid one day. 
And you seriously needed line locks on that thing, i'll help you install a set when you get another one.
Cheers.
And you seriously needed line locks on that thing, i'll help you install a set when you get another one.
Cheers.
#17
_Drag lc_
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Posted 08 August 2009 - 03:23 PM
hey bomber ill have to teah u how to do them before you teach michael to do them 
for a start get off the brakes.hehe
sorry for the thread steal im done here
Cheers Hayden
for a start get off the brakes.hehesorry for the thread steal im done here
Cheers Hayden
#18
_cruiza_
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Posted 08 August 2009 - 03:34 PM
everyone is a critic lol
In answer to question on brakes I was useing a line lock, multigrips on rear brake hose
rear brakes are ford rear caliper off XB GT same as diff and holden hq front rotors
As for area of 2.5 verses 3 in I wanted largest single pipe that would fit Graham said he could do 3in and did I liked single pipe as something different everyone else had duels I had been told 3in would flow better then deul 2.5 if someone wants to prove me wrong, more power to them. My car is red so it goes faster anyway
In answer to question on brakes I was useing a line lock, multigrips on rear brake hose
rear brakes are ford rear caliper off XB GT same as diff and holden hq front rotors
As for area of 2.5 verses 3 in I wanted largest single pipe that would fit Graham said he could do 3in and did I liked single pipe as something different everyone else had duels I had been told 3in would flow better then deul 2.5 if someone wants to prove me wrong, more power to them. My car is red so it goes faster anyway
#19
TerrA LX
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Posted 08 August 2009 - 04:36 PM
Sorry if offended you.
#20
GML-31
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Posted 08 August 2009 - 04:43 PM
I bet the owner of that factory was shocked when he saw his carpark...
#21
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Posted 08 August 2009 - 04:58 PM
I think 2 into 1 would make up for that.
#22
_cruiza_
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Posted 08 August 2009 - 05:41 PM
Sorry if offended you.
Its cool I get grumpy sometimes read things take them the wrong ask my wife she will tell you
#23
_cruiza_
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Posted 08 August 2009 - 05:51 PM
I bet the owner of that factory was shocked when he saw his carpark...
You don't know the half of it, I had permission to do it although the guy was not expecting so much mess and the other thing was it was next door to the local cop shop sort of
As for calulation on flow rate surface fiction of pipe is a factor making larger single pipe better then two smaller ones
#24
_mello92_
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Posted 08 August 2009 - 07:47 PM
As for calulation on flow rate surface fiction of pipe is a factor making larger single pipe better then two smaller ones
Yep, thats exactly what Ive been told, and not by idiots either.
#25
_Bomber Watson_
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Posted 08 August 2009 - 08:13 PM
hey bomber ill have to teah u how to do them before you teach michael to do them
sorry for the thread steal im done here
Cheers Hayden
Ah yeah i cant do them off the brakes yet.....Hayden is god, or is that runna202? Who is winning the skid comps now days???
Anyway, i agree, sorry for the thread steal i'll but out now to.
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