One difference i noticed immediately between the FWD Verada and the AWD is the perceived loss of power, (due to all the extra weight on the AWD I believe).
Most of the time it's not very noticeable but occasionally, such as when overtaking, it's really apparent.

I'm interested in any simple mod that can improve performance and a few ppl have mentioned headers and exhaust, the suggestion being to fit HM header and Lukey exhaust, I think.

Anyone done this on the AWD can talk to their experience about it?
I'd like to confirm if this provides a significant improvement and is worth it?
Are there any cons? What's the impact on N&V?
Is it a simple swap over job, or is there a bit of work or modification involved?
Also, are there any issues around insurance?
TIA

things were quiet around here and then all of a sudden there's 6 threads on extractors! :)

a search & read would have answered your question, but I'll do it too.

I've got a TJ AWD Sports - replaced the muffler when a hole formed. Lukey 2779 or something and it's good - a little more noise than the open Sports/VRX muffler, no change in power. If you have a restricted muffler you should get a gain in power.
I've just installed HM headers - recommended - I did it myself, bolt in job, saves over 6kg of weight.
I didn't notice a power increase, from just seat of the pants driving, but will one day go to WSID and compare my 400m time when all I had was the muffler.

Overall, my AWD is not slow, overtaking is fun & easy, mind you I do ring the tits off the valves & cams so either you're being soft on the accelerator & revs or you have some kWs to unleash with a good exhaust.

Cheers!
Graham.

http://www.aussiemagna.com/forums/showthread.php?t=98332

Thank you, from the info in the thread above the HM headers and Y pipe seem to be providing a good improvement.
I know nothing else about it. Would someone please provide a link the the HM web page for me?
And is there any special part number I should quote to them, or will they know what I need?

Try here: http://www.hmheaders.com.au/shopexd.asp?id=178&bc=no

I'm interested in any simple mod that can improve performance

Before you shell out for go fast bits, have you serviced the car and checked everything else is functioning okay? Things like throttle body and so on - simple but important stuff. If the car is in good service condition and you still feel its lacking in power then go for it, install the HM's and full exhaust.

I had the opportunity to drive my AWD with a few different exhaust combinations, pretty much trying everything in several different combinations. I'm now running HM headers, sports cat and a custom 2.5" cat back, but the HM's are the key item, not just for perceived power but for eliminating the drone. If you're AWD is not a sports variant then a rear muffler may help also.

HM RRP is $840, I sell them for $740 for a set and have them in stock. You should not have any problems finding someone to fit them for you as they are not hard to do

Changing your rear muffler from the stock twin outlet to a free flowing one will help BUT it will change how the car sounds. If you dont mind a little more noise and perhaps a little (only a little) drone then is fine.

HM RRP is $840, I sell them for $740 for a set and have them in stock. You should not have any problems finding someone to fit them for you as they are not hard to do

Changing your rear muffler from the stock twin outlet to a free flowing one will help BUT it will change how the car sounds. If you dont mind a little more noise and perhaps a little (only a little) drone then is fine.

Just be sure to get a price for fitting first. Sheesh. Exhaust shops in my town think it takes three plus hours to fit HM headers. True story. Takes me (with on arm and no hoist) 1.5 hours.

I called one exhaust shop - I asked "Give me a ballpark price to just install extractors? I'm told it's bolt on and I have all bolts & gaskets & the extractors"
They said - maybe $500. I said F that and did it myself - took me longer than 1.5 hours, but I dropped a couple of nuts & spent 30 minutes finding one of them ! :)

The best exhaust mod you can do is to fit HM headers and a VRX rear muffler. It's not loud and you'll gain genuine power. Any after market muffler is questionable and in my experience loses power and creates more noise.

I fitted the HM headers only to my TWII VRX and noticed an improvement in roll on acceleration, or mid range torque. More power, dunno, but an improvement for sure, but not night and day. A couple of the header bolts are a bit fiddly to access, but straightforward enough.

The best exhaust mod you can do is to fit HM headers and a VRX rear muffler. It's not loud and you'll gain genuine power. Any after market muffler is questionable and in my experience loses power and creates more noise.

Agreed about the HM's, but any decent aftermarket muffler that is a straight through design 2.5" in - offset /out - centre will free up more power compared to the stock baffled muffler.
I have a stainless magnaflow straight through on my AWD for example, same design & virtually identical size to stock baffled muffler.

The other advantage of an after market system, including the HM headers, is a reduction in weight. A few might laugh this off but when you add it up you can save around 15kg with a complete exhaust system change. That might sound like a drop in the ocean, but every kg counts toward improving power to weight ratio, which leads not only to better acceleration but to improvements in economy.

KWAWD, is yours the KW GTVi AWD or the KL Ei AWD? If former, then you already have the straight through muffler as fitted to the Sports/VRX and other GTV/i Veradas. When you overtake, do you just kick down or use the tippy to shift down a couple of gears? If former then if you normally drive sedately then it wont respond very quickly as it learns your driving behaviour (better to use the tippy). I use the tippy all the time and do not have overtaking issues (even with wife, 2 kids, boot full of stuff) on the highway. Bear in mind, I also have the 380 cams and SKR tune as well as modified intake to feed in cold air from outside (similar to the NZ CAI snorkel) as well as a 200CPSI metal cat.

KWAWD, is yours the KW GTVi AWD or the KL Ei AWD? If former, then you already have the straight through muffler as fitted to the Sports/VRX and other GTV/i Veradas. When you overtake, do you just kick down or use the tippy to shift down a couple of gears? If former then if you normally drive sedately then it wont respond very quickly as it learns your driving behaviour (better to use the tippy). I use the tippy all the time and do not have overtaking issues (even with wife, 2 kids, boot full of stuff) on the highway. Bear in mind, I also have the 380 cams and SKR tune as well as modified intake to feed in cold air from outside (similar to the NZ CAI snorkel) as well as a 200CPSI metal cat.
I've got the KL AWD. (Apologies about my handle here which is misleading). I don't think it comes with the EI designation, it's just the AWD?
I just use the auto in, er, auto mode, mostly. But overtaking feels less effortless than my KH, as if its holding back somehow.
I gotta say, the KL kicks down at the right times and all and I'm not necessarily flooring it at top speed when I get this feeling of holding back. It feels like its revving harder sometimes than the KH would be in the same scenario. I think it's noisier than the KH which probably gives me that impression, I dk. The KH can be slow to overtake at high speed because it won't always kick down, but it never felt like it was being held back, always felt free flowing. The KL just feels like its not breathing easily or something, it's hard to explain. Basically the car is heavier than the KH and naturally noisier given the drive train, so I put this feeling of "holding back" down to that, a perception thing. It's got to work harder to deliver the same performance as the KH, so rev harder and sound noisier right?
You're probably right about using the tippy, i do drive fairly sedately sedately most of the time. I'll try it, but I think any simple mod that improves performance is worth a go.
Sounds like ur car is quite a bit different to mine with those mods tho.

your kh will labour less because its fwd.

your kh will labour less because its fwd.
Ok, if you would take a minute to explain it? Is it just a function of the extra weight and drivetrain components as I thought?
Anyhow, that's why I was thinking of doing the HM headers.

Correct. KH FWD weighs less than a KL FWD which again weighs less than a KL AWD. The reason I said EI AWD is because the KL AWD is based on the Ei where as the KW is based on the GTVi.

The KL will also have the 5 speed auto where as the KH will have the 4 speed so the gear ratio's will be a bit different, I think that the 5 speeds are geared shorter than the 4 speeds.

Is it just a function of the extra weight and drivetrain components as I thought?
Your AWD is giving your KH more than 150kg head start (~10% more kerb mass than the KH). Not only that, but it is driving a lot more energy sapping drivetrain (somewhere in the vicinity of 50-60% higher losses than for an FWD auto based on dyno results I've looked at). The only things in the AWD's favour in this comparison are a 10% lower final drive ratio, slightly better cams (if the KH has #4s) and the most aggressive downshift points of any auto 3rd gen, but these advantages aren't anywhere near enough to balance the equation.

If you haven't already got the straight through muffler as others have suggested, it is by far the most bang for buck performance mod you will make. The AWDs do respond well to the HM headers due to the cost cutting design of the stock "collector" that joins the piping from each bank, but the reality is that the headers will cost at least twice as much as the muffler and deliver at best half the performance gain.

Unfortunately, as I've noted elsewhere, I believe that the AWD WOT upshifts are a bit too high (at about 5800rpm) for the stock engine/exhaust power/torque curves. I've not driven an FWD to know when the WOT upshifts happen in such cars but from the shift maps I would expect somewhere about 5400-5500rpm, which is closer to where I think the stock AWD upshifts should be.

Your AWD is giving your KH more than 150kg head start (~10% more kerb mass than the KH). Not only that, but it is driving a lot more energy sapping drivetrain (somewhere in the vicinity of 50-60% higher losses than for an FWD auto based on dyno results I've looked at).
As usual, WytWun, you're providing great info, thank you!

But I'm surprised now about the straight through muffler recommendation; so you're advocating that as being a much more significant mod over the headers with twice the performance gain?

Mal said earlier:

Changing your rear muffler from the stock twin outlet to a free flowing one will help BUT it will change how the car sounds. If you dont mind a little more noise and perhaps a little (only a little) drone then is fine.
I hate N&V. But I'm willing to try it if there's a noticeable improvement.
From what I understand, swapping the headers for the HM's will reduce some of the drone, so maybe I need to do both. I might just start with the muffler, sounds easier and cheaper?
Can anyone recommend any particular muffler? (I guess the OEM VRX are not available?)

OEM VRX, GTVi or sports off a wreck will be fine. AWD muffler has a shorter pipe so if you want direct fitment, get an AWD unit.

My redback drones horribly but I love it. If you want to avoid drone, don't get a redback. Lukey is popular.

OEM VRX, GTVi or sports off a wreck will be fine. AWD muffler has a shorter pipe so if you want direct fitment, get an AWD unit.

My redback drones horribly but I love it. If you want to avoid drone, don't get a redback. Lukey is popular.

HM headers will sort out the drone. Mine droned with the OEM straight through muffler. The immediate realisation of driving off with the HMs was how quiet it was (no more drones). It also creates a little burbling noise.

Magnaflow part number 14586 polished stainless, 2.5" in/out, Offset/Centre, straight through, full size type.
I know I sound like a broken record as I always recommend this muffler when the suggestion of choice comes up in a forum & yes I have one fitted to my AWD Verada. Compared to the Lukeys I've heard it isn't quite as growly but instead is deeper & beefier sounding which I love. It's also virtually identical in size compared to the stock muffler & is the same Offset/Centre piping configuration. Just get the exhaust shop to use the existing hangers off the old muffler & fit a shortish downward facing tip & you're good to go.

It's pretty much the same volume at idle and only marginally louder than a stock baffled Magna muffler when on the gas & it gives a nice wail at WOT.
Personally, I'd invest in the HM perry headers with Y pipe - For the AWD this is a must do if you are chasing better performance.

HM AWD part number for you OP if it is of assistance

HM116SS

But I'm surprised now about the straight through muffler recommendation; so you're advocating that as being a much more significant mod over the headers with twice the performance gain?
Apart from the T join (instead of a proper Y join) between the banks in the AWD the exhaust system in the later 3rd gens was quite reasonable for a locally made family car, with the only difference between the "sports" badged (VRX, GTVi etc) cars and the others being the use of the straight through muffler (pretty much a Lukey LR-2779). Mitsubishi's published figures indicate the muffler would be worth 8kW (peak).

The info I have suggests that the HMs could be expected to show a gain of no more than about 4kW (peak - a little bit more than that is gained lower in the rev range).

Just with the rear muffler only, I'd be looking to get either a stock muffler or a as close to stock as possible option. I had the rear muffler changed on mine, with stock headers/Y-pipe, and the drone was HORRENDOUS. Bad.

Replaced the headers with HM and the drone went away.

I'm not sure what brand/model muffler was put on, for reference, but it's a straight through thing and quite compact. I'll post a part number in the morning. If you just want to do the rear muffler the one that's on my car would be one to avoid.

kwawd, kim aka kj380 is selling magnaflow and berklee mufflers. best to get one of them and then the hm headers. as wytwun mentioned, the straight through muffler will bring your flywheel power from 154kw to 159kw. adding the hm headers will increase it to at least fwd sports/vrx flywheel power of 163kw plus a couple more to 165kw.

Magnaflow part number 14586 polished stainless, 2.5" in/out, Offset/Centre, straight through, full size type.
I know I sound like a broken record as I always recommend this muffler when the suggestion of choice comes up in a forum & yes I have one fitted to my AWD Verada. Compared to the Lukeys I've heard it isn't quite as growly but instead is deeper & beefier sounding which I love. It's also virtually identical in size compared to the stock muffler & is the same Offset/Centre piping configuration. Just get the exhaust shop to use the existing hangers off the old muffler & fit a shortish downward facing tip & you're good to go.

It's pretty much the same volume at idle and only marginally louder than a stock baffled Magna muffler when on the gas & it gives a nice wail at WOT.
Personally, I'd invest in the HM perry headers with Y pipe - For the AWD this is a must do if you are chasing better performance.
I hadn't thought about fitting. Do these after market mufflers just mount to the existing OEM brackets/hangers on the AWD or is there some modification required to fit them?

And is anyone else able to comment on the Magnaflow product versus the Lukey?

I hadn't thought about fitting. Do these after market mufflers just mount to the existing OEM brackets/hangers on the AWD or is there some modification required to fit them?

And is anyone else able to comment on the Magnaflow product versus the Lukey?

You get the exhaust shop to cut the hangers off your original muffler and weld them on to your new muffler they will also weld on the muffler to the flange pipe. For an exhaust shop, this is a straight forward job, nothing overly technical or difficult. As I said previously, this particular magnaflow is virtually identical in size compared to the original muffler. I'll pull out the camera and post up some pics later on when I'm back from work. I'll also get a sound clip organized and put that up also.

As for another opinion on the magnaflows, send AMC member ALSCALL a pm. He has the exact same muffler on his AWD i believe, but with a custom stainless steel mid pipe section. Mine's just the stainless muffler & stainless flange pipe only (though we both have the HM perry headers with Y pipe fitted to our AWD's)

The info I have suggests that the HMs could be expected to show a gain of no more than about 4kW (peak - a little bit more than that is gained lower in the rev range).
For some dyno charts, see: http://www.aussiemagna.com/forums/showthread.php?t=71053&p=1596077&viewfull=1#post1596077. On my TW VR-X AWD, the HM headers netted 9.6% more peak torque (20Nm) and 7.0% more peak power (7.4Kw) than stock. With HM headers, the output is more than the stock peak output all the way from 4400rmp to 5700rpm. At 5000rpm and lower, the HM headers consistently produce 8-10% more torque than stock.

So, i finally got around to this and have had the HM headers fitted, along with a freer flowing muffler, from a VRX

*** Big thank you to the fellows at MitsFix; Mal, Brendan and the rest of the team!
Fantastic job with no complaints at all. :) ***

Very first thing i noticed was how much quieter the car is - Headers paid for themselves on that point alone for me!
The new muffler can be a bit boomy in high gear at lower rpm, especially when going up hill... the AWD loves to stay in higher gears, but its not enough to bother me and even sounds quite sporty sometimes - lol for a boat that is.

There has been an improvement in how the car feels too, doesn't feel like its "holding back" anymore. Picks up very well from standstill and even overtaking at 100 k's feels effortless now.

GF commented on the quieter ride too and told me she expects me to stop complaining now, heh.

I'm very happy and can now appreciate the extra gear over my KH. The KH pulls well but can be slow while building up revs in 2nd gear whereas the 5 speed feels quicker through the range.

I highly recommend the headers to all the AWD drivers.