[Lakes]

Hey Thumper, sorry m8 i'm profoundly deaf, so can't hear the sound from the video.
but the results sound good. you said it sounds like a WRX, they are horizontally opposed like a old VW, i have heard them in the past and did not like VW's sound is it that bad?

[Dazzler]

Hey Lakes,

If you give a standard i30 CRDi a bit of a rev, I reckon it sounds a bit like a WRX (but a bit more subtle) From what I could hear on the video it was still similar but a bit more free revving...

Is that a fair description folks...?

[Thumper]

Pictures of the exhaust.

Picture one, 2.5inch piping from the flange, back. (All new exhaust painted black)



Picture two, original rear muffler.



Reasons why I changed the exhaust, very restrictive piping into and out of the muffler.




Close up to the front of the exhaust system showing the particulate filter and resonator.



Will get a better sound file later.  

[Lakes]

Thanx Thumper good pic's, i like the way you kept the stock system with stock mounts still in place, i also like the way the stock system is bolted on nice and strong well mounted. i have seen some exhaust places cut off the stock mounts to use on an aftermaket system i don't like that. i like it the way you have had it done! very professional! has it still got the resognator in place? also just wondering what you used to paint the new system black with and what the reason was? also what brand of turbo muffler are you using? looks like a worthwhile mod to me.
thanks again for taking the time to post and take pic's. have you had time to test economy at rev's like you used to get your great economy numbers? as i'm really interested in things like this. also was there a weight saving in this? was it noticeable or just minimal?
cheers

[Dazzler]

Hey Thumper...

Lovely Pix (didn't think I'd ever say that about pictures of an exhaust but I'm excited...   ) This might be the Mod I just have to have will be interested to see if it helps economy as well as performance! Did you get a national company to do the job?

Regards,

Dazz

[Waja]

thumper, sounds like everyone wants to kill you for your muffler system now!!  

[Lakes]

Hi Link, i might be wrong but i think Thumper posted the price @ $280 if you read back in the post you might find it too.

[Waja]

oops >< missed that info! thanks for that lakes! daym...$280...hopefully the fuel efficiency makes up for that ><

[Lakes]

Don't think i would worry about it as i'm cheap like the feel of money
cheers

[Dazzler]

Hi Lakes,

I'm a cheapskate too but as Thumper says "he can bolt the original back on in about 10 minutes" so essentially he now has a spare...

Is the exhaust covered for a full 5 years under warranty (I don't usually keep mine that long so never had to replace an exhaust)

Got a mate that's had 2 or 3 Mitsubishi Magnas and he has had to replace burnt out exhausts every 18 months or so! (expensive)  

Cheers,

Dazz

[Thumper]

I made sure that the exhaust was made in such way that NOTHING was cut from the original system. Everything can fitted back, factory stock in under 10mins.  8-)

The nice sound is an added bonus!  



Next will be one of my 'economy' runs, with the intercooler cover fitted, to see if I can beat 3.8lt/100km  

[EymaTeapot]

Thumper, Thats great man

Just wondering though how long it was between the two ful runs with and with out flow through exaust. Reason i ask is if the car was relatively new first time, and run in wth several thousand Kilometres on it, that could make a difference. I have just over 6000k on mine now and have noticed a small improvement in fuel economy.

Either way, The results you post sure look promising.
I for one am very interested in following your example on the exaust. I have done nearly everything else i can now, short of a body kit.

[Thumper]

EYMATEAPOT, tell you what, since it's only a 10 min job changing the exhaust, and I'll be going back down to Cooma shortly, again, I will be taking of the exhaust and putting the factory one back on, to measure the difference.

While it's off, if you wish to borrow it for a day or two, be my guest!  8-)

[Dazzler]

Hey Eyma....

Hope you take up the offer would be interested in your feedback about the exhaust if you notice a marked difference in performance and economy as well I will definitely do the upgrade!

Not that I doubt you Thumper but that would be the clincher!

rgds,

Dazz

No pressure

[EymaTeapot]

Hi Thumper,

I am very tempted by your offer.
I dont have a Mechanical bone in my body, would your offer extend to helping me fit it? I would provide the beers of course. ( hope you like homebrew)

[Thumper]

*Chuckles*

Sure, no problems. It's rather easy, and I'll show you how. (Only needs one spanner and several minutes)

I'm curious to see if it's just my motor freeing up, or a definite difference!  

Let me know when you have some free time.

[EymaTeapot]

Thumper,

That would be great. Just let me know when you intend to do next fuel run and i will fit in around you.

By the way, why have you selected the name Thumper?
Is it something to do with the Bambi's mate, the cartoon rabbit, or do you just like whacking people?

[Lakes]

Thumper, sounds like the restrictive exhaust kills economy at speeds above 90kph, wonder what would happen if you used the cover on the intercooler in cold weather now? the pipe might be leaning it out a bit at speed?
now your taking a big risk giving Teapot that pipe you won't be able to catch him if he likes it
cheers

[Lakes]

*Chuckles*

Sure, no problems. It's rather easy, and I'll show you how. (Only needs one spanner and several minutes)

I'm curious to see if it's just my motor freeing up, or a definite difference!  

Let me know when you have some free time.

Thumper, you owe it to yourself to find a good wheel driven dyno and do the test! but make sure you have heat proof gloves, go there with stock pipe and do  three power runs, you need three to get an accurate # as the second and third power runs will show a gain over the first run just normal on dyno's ( oil warms up, cobwebs blow out so on ) then get under the car remove stock pipe fit the pipe you had made up, would be good if you could fit an air sensor in the pipe to see how air fuel ratio is effected, just i've never used one with a diesel but i can find out , i have an air sensor with AFR read out and play back real time, myself if they can be used with diesel i would let you use it.

[Thumper]

Thumper,

That would be great. Just let me know when you intend to do next fuel run and i will fit in around you.

By the way, why have you selected the name Thumper?
Is it something to do with the Bambi's mate, the cartoon rabbit, or do you just like whacking people?

No problems.  

Thumper, sounds like the restrictive exhaust kills economy at speeds above 90kph, wonder what would happen if you used the cover on the intercooler in cold weather now? the pipe might be leaning it out a bit at speed?
now your taking a big risk giving Teapot that pipe you won't be able to catch him if he likes it
cheers

I'm in the process of fitting more temperature probes, so I can record what exactly is going on when I cover the intercooler.

As for leaning out, that is how a diesel engine works. (They are designed to run very lean when on light/low throttle application)

Down low, an increase, up high, an increase, in the mid-range, not sure yet.

Yeah, keeping my mods simple.  8-)

As for the air sensor, again, a diesel can run too rich, hurting performance. Yet, running too lean, well, it doesn't go! (Simple function of diesels. Just add more fuel for it to go faster!)  

[Lakes]

what AFR is ideal for diesel Thumper?
the dyno your talking about sounds like what i have seen for bikes they hook the chain to the dyno to eliminate the tyre friction and a few other things. i still like the engine dyno's the best but have to pull the engine out so too much trouble for a street car.
is your friend building the dyno?

[Thumper]

what AFR is ideal for diesel Thumper?
the dyno your talking about sounds like what i have seen for bikes they hook the chain to the dyno to eliminate the tyre friction and a few other things. i still like the engine dyno's the best but have to pull the engine out so too much trouble for a street car.
is your friend building the dyno?

Well, diesel is a fickle mistress, compared to petrol.

A petrol engine, stoichiometric is 14.7:1, it will run at this range almost all the time. (Will try to)

A diesel engine, stoichiometric is 14.42:1, with a very big BUT!

When a diesel engine runs at stoichiometric, it will create plumes of black smoke. (Yet it will make the most power at this A/F ratio)

A normal diesel engine runs about 60-100:1 A/F ratio at idle. Up to 40:1 on the highway.

Allowing a diesel to breath better will allow more fuel to be used, thus creating more power.

Some reading on the subject:

http://www.diesel-central.com/News/cackle.htm
http://en.wikipedia.org/wiki/Diesel_engine
http://www.eng-tips.com/viewthread.cfm? ... 502&page=1


As for the dyno, I am waiting for it become available for a 'reasonable' price.  

[Lakes]

Thanks Thimper
think 14.5 AFR on a petrol is for economy but can't use wide open throtle for too long or would damage motor, i found my petrol motor made the best power at 13.0 AFR but different motors seem to like different AFR some petrol i've seen liked it in the high 12's this is with no turbo.
this set up i have has a G force reading and a few other things and if you program weight and so on and take it for a drive with it hooked up it can give very close HP numbers, can play it back on lap top.
thanks for the links i'll look at them.

[TheBunyip]

Now for anyone who wants to know more about why this is a god idea....

Try this quote to get you started

Diesel Exhausts

So when thinking about petrol engine and diesel engine exhausts, what are some of the differences to be kept in mind?

 •    Depending on the age of the diesel car, the exhaust might contain multiple mufflers, cat converter(s) and a particulate filter. If all these components are present, upgrading the exhaust to a genuinely higher flow design might be very expensive. In fact in some cases it might be impossible, especially if emissions are to remain legal.

 •   Despite the lower diesel engine exhaust temperature and different combustion behaviour, diesel and petrol engine mufflers are interchangeable – diesels don’t have unique mufflers.

 •   Diesels have very high gas flows all the time. In a turbo diesel, the gas flows will increase with load, as is the case with a petrol engine. But when off-boost, eg in light load cruise at 1500 rpm, the diesel engine will be inhaling and exhaling the same amount of air as a petrol engine of the same capacity would be at a full throttle 1500rpm! Therefore, the average mass airflow is much higher in a diesel engine than a petrol engine. As a result of this,a restrictive exhaust is likely to cause significant pumping losses (where the pistons have to push against exhaust back-pressure) much more often in a diesel than in a petrol engine. So while maximum exhaust flow of a 2 litre turbo diesel running 15 psi boost is no greater than of a petrol 2 litre turbo running 15 psi boost, on the road any backpressure will be felt more often by the diesel. Bottom line: in diesels, exhaust flow is very important! (My Italics.)

This is the conclusion from a great article at AutoSpeed. http://autospeed.com/cms/A_109291/article.html

Now don't all rush out and upgrade your CDRi exhausts.

[Shambles]

Splendid read that. Thanks TBY  :roll:  

[Dazzler]

It's OK Shambles...

He was thinkin' of my car...

[EymaTeapot]

Good Article Bunyip.

Sound like there might be some logic in what Thumper has been preaching us all this time.
Sorry Thumper, i never doubted you...Really.

[Thumper]

600km 3/4 tank. 800km 1/2 tank. 1050km 1/4 tank.

Still waiting for the fuel light to come on.

This is pure highway driving at normal highway speeds (110km/h)

[Lakes]

Thumper what is the best L/Per 100K you have seen since fitting the lower restriction system?

[Thumper]

Normal highway (110km/h) and city peak hour, 4.44lt/100km

If I slow down to 90km/h on the highway, 3.7lt/100km is what I have done from Canberra to Sydney, then back to Canberra.