[in_the_blender]

HI guys and gals, im brand new, with a pretty much brand new Jimny Sierra and I have a few questions for you.

I started almost as soon as I had the keys, getting a 40mm lift with King springs and OME shocks, 235/75/r15 Federal Couragia muddies and a set of diff breathers done by the fanatical Alan from Piranha 4x4. It needed a fair bit of guard trimming to get them to fit without rubbing, but it all works well (despite having a small incident on a fast bit of trail and bending the tabs holding the front bar in to the tyres, all fixed after a bit of trail panelshop work) The springs still wont seat into their mounts at the back, which makes them bounce on the rebound on big hits, but whatever, I'm happy and its amazing off road.

Next up is an xrox bar and a snorkel before the trails get too wet to gamble on in winter (Had water flowing over the bonnet a few weeks ago, a little unnerving to say the least)

What im curious about is exhaust work, I have read a few posts on here about extractors and 2" exhaust systems being the way to go, but I am not sure how I want to approach it. The Japanese have some pretty amazing cat back systems, and as far as I can tell, some places use modified superbike mufflers from places like Yoshimura... Now, seeing as the Hayabusa is the same displacement, and capable of creating a much higher flow than the car, would there be any feasable way of modding a stock Busa muffler to suit the Sierra or am I just making this needlessly complicated?



Like this, only not spending $1500

I like the idea of making it sound a bit unique, and im not fussed if its a little noisy.

One other thing I was curious about was those return to center things, how do they work, how will it change my car off road, and do I actually need one?

Cheers guys, I'm completely smitten with this little beast, and I'll definitely be hanging around here a bit.

[Marko_SJ]

in_the_blender wrote:

HI guys and gals, im brand new, with a pretty much brand new Jimny Sierra and I have a few questions for you.

I started almost as soon as I had the keys, getting a 40mm lift with King springs and OME shocks, 235/75/r15 Federal Couragia muddies and a set of diff breathers done by the fanatical Alan from Piranha 4x4. It needed a fair bit of guard trimming to get them to fit without rubbing, but it all works well (despite having a small incident on a fast bit of trail and bending the tabs holding the front bar in to the tyres, all fixed after a bit of trail panelshop work) The springs still wont seat into their mounts at the back, which makes them bounce on the rebound on big hits, but whatever, I'm happy and its amazing off road.

Next up is an xrox bar and a snorkel before the trails get too wet to gamble on in winter (Had water flowing over the bonnet a few weeks ago, a little unnerving to say the least)

What im curious about is exhaust work, I have read a few posts on here about extractors and 2" exhaust systems being the way to go, but I am not sure how I want to approach it. The Japanese have some pretty amazing cat back systems, and as far as I can tell, some places use modified superbike mufflers from places like Yoshimura... Now, seeing as the Hayabusa is the same displacement, and capable of creating a much higher flow than the car, would there be any feasable way of modding a stock Busa muffler to suit the Sierra or am I just making this needlessly complicated?



Like this, only not spending $1500

I like the idea of making it sound a bit unique, and im not fussed if its a little noisy.

One other thing I was curious about was those return to center things, how do they work, how will it change my car off road, and do I actually need one?

Cheers guys, I'm completely smitten with this little beast, and I'll definitely be hanging around here a bit.

The extractors will scavenge the cylinders better than the original manifold hence giving performance and possibly economy improvements.

This with a 2inch system is going to be better than the busa muffler setup on your stock exhaust plumbing which will only create more noise.

I see no issue with a busa muffler fitted to the performance system, so long as you can fit it neatly and out of the way.

[in_the_blender]

I wouldn't consider just adding a muffler, I know the best way to increase flow is to add extractors and a better cat in combination with one.

I reckon its a doable mod, a bit different to a fart can, might sound better, bit less rice burner.

[Jezza86]

[in_the_blender]

haha its pretty loud, haven't hit the redline too often just yet, its only got 3000 km on the clock.

How is it just cruising around? My old Subi had a bit of a drone on the freeway that got tiring after a while.

[Jezza86]

"bit of a drone on the freeway that got tiring after a while" would cover it.

in short the kits you are looking at from japan may not suit an aussie jimny.
in japan they have the "Water-cooled 4-cycle series 3-cylinder turbo intercooler"
and the exhaust comes out the rear left, not the rear right as it does in australia.

[in_the_blender]

The ones i've seen are almost unanimously right hand exiting, Im definitely not shelling out 1500 bucks for a pretty muffler though. I reckon I'll get an Aussie shop to fab it all up and try it out with the moto muffler for shits and giggles.

http://www.findjapaneseparts.com/mt/mt- ... y&limit=20 its a shame we can't get all these parts here... So awesome.

[pete_79]

You can get lost for hours in those after market Jap parts sites.

[alien]

Please don't call your Jimny a Sierra... it's a Jimny, not a Sierra.

[DC3PTIKON]

Arent they badged as Jimny Sierra?

[sur5a]

i call mine a sierra.
i better rip that badge off it

[in_the_blender]

The badge puts emphasis on the Sierra, i'm calling it a Sierra.

Or Honey Badger... Definitely this cars spirit animal.

[Gwagensteve]

in_the _blender,

Your car is a Jimny. Its model designation is JB. My car is a Sierra, its model designation is SJ. The "sierra" badge is a marketing exercise to highlight the "rugged heritage" of the model. Suzuki did the same thing with the Maruti - stuck "stockman" stickers on them. You can call it whatever you like, but for the purposes of choosing parts and asking for advice, best to call it a Jimny because that's what it is.

As for exhaust modifications, dyno research has shown no gain (and possibly lost) power from messing with the exhaust on these models. So long as you recognise you're not making the car go better, and you're really just messing with aesthetics and noise go crazy and fit any muffler you like. Remember too that the nature of the noise an engine makes is really a function of capacity, cylinder head design, and compression ratio. All sierras pretty much sound the same, they're just noisier or quieter depending on how little muffler the owner runs. - same for any car. Personally, I think loud cars are a bit of a pain offroad. A guy who lived in our street had a bike muffler on his sierra, and got a defect for excessive noise. (it was REALLY loud)

Personally, the cost isn't worth it and I'd only bother to mess with the exhaust if the stock exhaust was damaged offroad. I recall these motors have the cat integrated into the exhaust manifold, so adding extractors requires you to purchase a cat as well. All up a lot of money and hassle for little to no gain.

Steve.

[DarkHorse]

Oh god, where to start...

A generic 2" stainless hi-flow muffler will cost you something like $500 fully installed.
A [I]PAIR[/] ('Busa's are dual exhaust, unless you can find someone to only supply one) of bike cans will cost you at least US$700 (more for big-name brands like Yoshi, Akra, Two Bros etc) before you even get them shipped half way around the world.

Just because they are the same engine capacity doesn't mean they are a suitable design. As above, the Busa runs a 4-2-1-2 dual exhaust, so each muffler is only (indirectly) taking 670cc worth from the equivalent of two cylinders. The motor runs a 12.5:1 compression ratio and develops 128kw at 10,000rpm - when it hasn't yet reached it's redline. None of this remotely resembles your Jimny's 1328cc, 9.5:1cr, 62kW M13 that relines at what, 5,500rpm?
This is not to say that it wouldn't actually suit, just that your basis for assuming it would is seriously flawed.

If it's just for looks forget about it, it will be covered in mud and road grime, tarnished and dinged up soon enough.

If it's for the noise you're gambling on an unknown... as Steve said the muffler alone isn't going to make your car sound like a Busa... it might sound like a lawnmower or a sewing machine for all any of us know.

I don't know enough about the late Jimnys to suggest your best option, but this ain't it.

[jdk81]

+1 to what Steve said about the performance.
Im skeptical about the shops making extractors. Without flow testing etc there's no guarantee it will be better.
Auto manufacturers are looking at easy power and fuel economy gains, flow testing is and has been happening.

As per noise/muffler
Find a slip on from an old busa, gsxr, r1, r6, cbr etc.
A pre dented and scratched wont be too bad.
I would (and have) looked for stock pipes. The aftermarket ones arent as great as advertised.

I had an r1, and mates with various sports bikes all with various mods.
Unless huge dollars, in the end the mods mostly made a diff in noise and/or appearance
Its so much like 4x4 etc
Most mods make it look like its better, but often make it worse.

[Marko_SJ]

jdk81 wrote:

+1 to what Steve said about the performance.
Im skeptical about the shops making extractors. Without flow testing etc there's no guarantee it will be better.
Auto manufacturers are looking at easy power and fuel economy gains, flow testing is and has been happening.

As per noise/muffler
Find a slip on from an old busa, gsxr, r1, r6, cbr etc.
A pre dented and scratched wont be too bad.
I would (and have) looked for stock pipes. The aftermarket ones arent as great as advertised.

I had an r1, and mates with various sports bikes all with various mods.
Unless huge dollars, in the end the mods mostly made a diff in noise and/or appearance
Its so much like 4x4 etc
Most mods make it look like its better, but often make it worse.

Don't know about road bikes, but usually on the trail bikes all it does is usually take power and torque from the bottom and add it somewhere else.

Oh, and don't forget.... all importantly, makes more noise.

[Mike57]

If you want more noise just change the muffler. In doing so you will void your engine warranty. You have already voided most of your drive train warranty with the tyre selection so maybe that is not an issue any more. If you add extractors it will also be illegal and stuff up the antipollution sensors. Your model has a pre cat in the exhaust manifold with sensors and any change will require some careful thought. Alan at Piranha would not touch mine when he saw it.

Also extractors will not improve performance or fuel economy on this model. The original Suzuki manifold is already the 4:2:1 system and a pretty good design IMO.

In addition they would be illegal but it seems that may not a concern to you.

I also agree it is a Jimny and not as capable as a Sierra but a whole lot more comfortable and easier to drive.