Cat back exhaust 4 AU 6???

aufairmontghia · 15-07-2009, 08:35 AM

Hi All.

I'm tossing up whether to fit a 2.5inch Cat back exhaust to my AU S1 Fairmont Ghia 6 VCT.

Just wondering what the benefits are? What brands to go for?? How loud is it going to be??? I have the standard system at the moment but no resonator. It sounds OK but that's all....

Also while on the subject, what extractors would fit if I'm running LPG & the gas convertor sits vertical against strut tower??

I've heard either mod really opens up the 6 as far as performance...

Any help would be appreciated!!!!

Cheers

MrXr6Tickford · 15-07-2009, 12:09 PM

Please before posting a new thread, use the search function!!

This is what it's there for!

AUbigfoot · 15-07-2009, 12:51 PM

I have a fairmont on gas. I got a 2.5 lukey cat back and I'm very happy with the sound as it has more of a crackle and pop rather that trying to sound like the loudest thing on the street. You will notice a few more kw's (perhaps 3-5 am I right?) here and there, and as you said it can really open up the rest of the system for you to get headers etc.

Post a picture of what lpg converter you have and where it is located and that might help a bit more as most converters cause problems space wise for decent headers.

The Monty · 15-07-2009, 01:33 PM

3 inch FTMFW!!!!!!
2.5 inch is good.
Not sure about the extractors.

grandpa_spec_F6 · 15-07-2009, 01:48 PM

2.5" is fine if you dont want to run boost, i've got one with a single straight-through muffler, god I love the rumble as you go through tunnels, but as it gets warm it gets quieter so good in a way, doesnt attract much attention as you putt around town.

3" is ok however if you give it some gas though you could deafen a small child :S
At least thats what my mates 3" systems sound like...

Dauphin · 15-07-2009, 02:26 PM

With a 2.5" system on the VCT six, my experience found that a 2.5" system with two mufflers and high-flow cat and headers will be very easy to live with and attracts no attention.

Replace one of those two mufflers with a hotdog and it's still pretty boring and a bit droney inside the cabin.

Replace both mufflers with hot dogs and you'll get a nice deep idle and a nice growl when you go above about 2,500 revs, so you can put-put around town easily. Going through tunnels is a real surprise sometimes.

In this situation, there's a bit of drone in the cabin around 2,000 revs but you can't have a louder exhaust without some drone.

White_sr_taxi · 15-07-2009, 03:58 PM

i got a redback on mine, its not as droney as my mates EB i have a feeling its because the newer redback on mines glass packed. scares the p platers in there matchbox ricers when you give it some.

frd906 · 15-07-2009, 05:53 PM

http://www.youtube.com/watch?v=cAx_c4ttjt4 new exhaust video
thats my exhaust

Dauphin · 15-07-2009, 06:11 PM

That's pretty full on, frd906! Sounds loud. What has been done to get that sound?

The Monty · 15-07-2009, 06:17 PM

3 inch from inside/outside on start up:
http://www.youtube.com/watch?v=XuDI0KyimBU

3 inch taking off:
http://www.youtube.com/watch?v=A5NuP...eature=related

3 inch incar run:
http://www.youtube.com/watch?v=qiXMy...eature=related

2.5 inch Lukey on skidpan, no extractors or hi flow cat, which is why it sounds so deep. Possibly the best sound from an AU from inside the car IVe heard, from the outside though it sounded very flat and not as good:
http://www.youtube.com/watch?v=-OQUJ41D_4c

3 inch setup is Pacemaker comp extractors, 3 inch cat, 3 inch cat back, single straight through muffler, and no res.

frd906 · 15-07-2009, 07:35 PM

i have a 2 and half inch stainless steel muffler, very small muffler smaller then the redback and other brand name systems, paid $280 from my local exhuast shop, 1 guy owner

set of motovatior extractors with a 3 inch opening to a 3 inch high flow ceramic cat then which goes to my 2 an half inch system. paid $350 for wreckers]

Sox · 15-07-2009, 09:07 PM

A 2.5" single system is the best for these sixes IMO.
1 good quality muffler and a hotdog if you want it pleasant, and no hotdog if you want it to drone and be a bit louder.

The JMM race headers are best extractors IMO. Well designed with a primary that's not too big, and very long secondaries. They give a very broad spread of power.

A set up like the above can't be improved on IMO.

frd906 · 15-07-2009, 09:13 PM

whats imo, plus you have never seen my car or vids have you lol so dnt say it cant be improved when you havent seen my car in flesh

Sox · 15-07-2009, 09:28 PM

Quote:

Originally Posted by frd906

whats imo, plus you have never seen my car or vids have you lol so dnt say it cant be improved when you havent seen my car in flesh

IMO = In my opinion.
What gives you the idea I was referring to your post?
And even if I was, I don't need to see your car to know what works.

This 2.5" VS 3" thing has been done to death on these forums, and if you're not producing 180rwkw plus, then a 3" is a waste of money.

frd906 · 15-07-2009, 09:34 PM

i dnt have a 3 inch system i have a 2 and a half inch system with a 3 inch high flow cat and extractors big difference hey

Sox · 15-07-2009, 09:38 PM

Quote:

Originally Posted by frd906

i dnt have a 3 inch system i have a 2 and a half inch system with a 3 inch high flow cat and extractors big difference hey

Whatever it is, be happy you like it.
My opinion is just my opinion.

blueoval · 15-07-2009, 09:48 PM

Quote:

Originally Posted by Sox

...This 2.5" VS 3" thing has been done to death on these forums, and if you're not producing 180rwkw plus, then a 3" is a waste of money.

I have more than 180rwkw and am still running a 2.5" system. I reckon I can push more out of the motor before I need to re-do the exhaust. I reckon going to 3" is for those pushing more than 220-250rwkw. But thats just my opinion.

Sox · 15-07-2009, 10:13 PM

Quote:

Originally Posted by blueoval

I have more than 180rwkw and am still running a 2.5" system. I reckon I can push more out of the motor before I need to re-do the exhaust. I reckon going to 3" is for those pushing more than 220-250rwkw. But thats just my opinion.

I think you could produce more power with a 2.5" too, but I would imagine that much beyond 180rwkw you would be sacrificing some top end power.
Personally I reckon a dual 2" would be better than a single 3".

blueoval · 15-07-2009, 10:16 PM

Quote:

Originally Posted by Sox

I think you could produce more power with a 2.5" too, but I would imagine that much beyond 180rwkw you would be sacrificing some top end power.
Personally I reckon a dual 2" would be better than a single 3".

you could be right there, but i dont reckon it would sound good on a six. Love to proven wrong though.

Sox · 15-07-2009, 10:28 PM

Quote:

Originally Posted by blueoval

you could be right there, but i dont reckon it would sound good on a six. Love to proven wrong though.

Yer, I've heard a few over the years, but mainly on older F series and X series Falcons, and they sounded pretty crappy. On these higher revving engines, they might be ok.

Mmmm, we need a guinea pig!
Where's Stav and his wagon.......

The Monty · 16-07-2009, 02:59 AM

Quote:

Originally Posted by Sox

IMO = In my opinion.
What gives you the idea I was referring to your post?
And even if I was, I don't need to see your car to know what works.

This 2.5" VS 3" thing has been done to death on these forums, and if you're not producing 180rwkw plus, then a 3" is a waste of money.

I pretty much agree, I think its mostly just personal choice. There is no proof for either being better or worse until we hit big power. A three inch system isnt sacrificing any power over a 2.5, and vice versa.
I got my 3 inch for a good price with a hi flow cat, for when I was going turbo, but still used it when I sold all my turbo gear off. Seeing as Ill be going S/C with this car, I used the three inch on it when I sold the Monty.
The sound difference also is much of a muchness between the two, only difference will bear in the type and size of mufflers you use, resonators, and hotdogs. Just because you have a three inch doesnt mean its loud at all.

aufairmontghia · 16-07-2009, 10:49 AM

Gr8 feedback Guys...

I'm getting a 2.5inch mandrel bent redback cat back system for the Ghia today. Installed for $330 I can't argue with that!!!

I've had redback systems before & was happy with them but not on a Ford.

I'm on LPG but either way it should open her up abit & go alot better...

Will see tonight!!!

blueoval · 16-07-2009, 12:07 PM

Quote:

Originally Posted by aufairmontghia

Gr8 feedback Guys...

I'm getting a 2.5inch mandrel bent redback cat back system for the Ghia today. Installed for $330 I can't argue with that!!!

I've had redback systems before & was happy with them but not on a Ford.

I'm on LPG but either way it should open her up abit & go alot better...

Will see tonight!!!

Nothing wrong with redback systems. I have one on my car. Combined with the s/c its making good power. Plus I have an extra muffler fitted for added quietness and stealth sound.

Dave_Obsession · 16-07-2009, 03:25 PM

I spoke to the guys at Sureflo Exhaust (site sponsor) when I was getting my Ballistic Cat, and they were of the opinion that Redback was a much better option for Falcons than the Lukey......higher quality product.....

MAD · 16-07-2009, 03:52 PM

Quote:

Originally Posted by Sox

Yer, I've heard a few over the years, but mainly on older F series and X series Falcons, and they sounded pretty crappy. On these higher revving engines, they might be ok.

Mmmm, we need a guinea pig!
Where's Stav and his wagon.......

The old 250 2v sounded fantastic with dual exhaust.
I'm yet to hear it on a crossflow, and have always wondered myself, but to scared to shell out the dough to find out it sounds crap.

pmpdau · 16-07-2009, 03:55 PM

Quote:

Originally Posted by aufairmontghia

Gr8 feedback Guys...

I'm getting a 2.5inch mandrel bent redback cat back system for the Ghia today. Installed for $330 I can't argue with that!!!

I've had redback systems before & was happy with them but not on a Ford.

I'm on LPG but either way it should open her up abit & go alot better...

Will see tonight!!!

Just wondering with that price, whats included? And where abouts are you getting it done.....for that price I might get mine done too :P

Sox · 16-07-2009, 06:11 PM

Quote:

Originally Posted by The Monty

I pretty much agree, I think its mostly just personal choice. There is no proof for either being better or worse until we hit big power. A three inch system isnt sacrificing any power over a 2.5, and vice versa.

Without going into a tit for tat argument here, I actually believe a 3" will sacrifice some low down power.
How much is any ones guess, and would need back to back dyno runs to show it.
On the other hand, a 2.5" system is practically ideal for a 4L 6 with a power spread from say 130rwkw to 180rwkw.
That's just my opinion based on what I've learnt over the many years, and it's also shared by my exhaust dude who's been in the game for a very long time.
It's all about air speed and scavenging.
A clue is also the size relationship between TB and exhaust.

Quote:

I got my 3 inch for a good price with a hi flow cat, for when I was going turbo, but still used it when I sold all my turbo gear off. Seeing as Ill be going S/C with this car, I used the three inch on it when I sold the Monty.

Sounds fair enough.

Quote:

The sound difference also is much of a muchness between the two, only difference will bear in the type and size of mufflers you use, resonators, and hotdogs. Just because you have a three inch doesnt mean its loud at all.

True enough, but it is more difficult to make a 3" as pleasant as a 2.5".
That goes for any increase in pipe diameter, nature of the beast.

Amyway, it's getting off track so I'll let it go here.

Sox · 16-07-2009, 06:20 PM

Quote:

Originally Posted by MAD

The old 250 2v sounded fantastic with dual exhaust.

You reckon?
I always thought they sounded like someone farting down a drain pipe.

:

Quote:

I'm yet to hear it on a crossflow, and have always wondered myself, but to scared to shell out the dough to find out it sounds crap.

Do it.

aufairmontghia · 17-07-2009, 10:58 AM

Guys

Had Redback exhaust fitted yesterday & let me say was quite surprised!!!

One thing for a 2.5inch system with straight through muffler & resonator, it was very quiet.... There is a subtle note on idle & the same while driving!!! I was expecting a loud exhaust but NO.... Considering I dropped the standard system less resonator.... which was loud or maybe more boomy....

The other noticable thing was the performance.... I was blown away how much better the car actually drove!!!! Heaps more power, acceleration & breaths alot better on LPG!!!!!!

I'm RAPT..... :hihi:

Dauphin · 17-07-2009, 11:05 AM

Congrats!

Make us a video!