Beaudesert Exhausts

[canojeckyl]

I've recently had an exhaust 'upgrade' from Beaudesert Exhausts. From the standard on the diesel to a 2 3/4 inch straight through.

The ute (dual cab, diesel, 3.2L, 2006, ML) still drives well, but fuel efficiency has gone up 10-20%. Has anyone had these problems?

Andrew.

[snowman]

do you mean fuel efficiency has gone down?

in other words it is using more fuel?

[QueenslandeR]

I got a quote from these guys the other day, and they stated that you would get better fuel economy by approximatly 12%. How many Litres per hundred were you getting before and after?

[canojeckyl]

Sorry...yes snowman, fuel efficiency has reduced... :p Woops

Was getting about 9.9L/100km before modification (with a DP chip), then after new exhaust, has increased to about 10.5-11L/100km.

I've removed the DP chip and sent back to manufacturers for recalibration (DP suggested to try this), and now it's up to about 11.8L/100km.

Not particulary happy (at least it's still driving well).

[QueenslandeR]

Is that going off your computer or when you refill? I dont see why it would make it any worse, did you contact the exhaust shop about the problem, i'd love to see what they had to say

[canojeckyl]

Fuel efficiency going off both. My computer usually calibrates pretty closely to my actual fuel usage.

Contacted Beaudesert Exhausts, and they claimed that it's obviously due to the DP chip (but...when I take the DP chip out, it makes the fuel usage even higher).

Spoke to some guys from the diesel centre (?) bayside (?) Brisbane. Apparently, there have been some problems with exhaust upgrades on the Nissan Navara and some tritons where the exhaust confuses the car, and causes lots of problems. Also some discussion as to the size of the exhaust (BE fits a standard modified exhaust to Tritons 2 3/4 inch, so there's not much choice, unless you want to start making calls on the mods yourself [I'm a vet, so am guided by others in their fields of expertise]).

The diesel guys were suggesting there may be problems with the exhaust being too big (likened to having a hose with nothing on the end, or with your finger on the end - get more force of water rushing out with some resistance in the system causing a pressurised flow through). There is of course back pressure to consider also, but this is why we look at fitting a modified exhaust anyway isn't it.

Let me know your thoughts.

[Joe]

I have heard that 2.5 is the max you should go to with the 3.2, but hey, I'm just a printer and wouldn't know for sure

[al coholic]

Daryn just organised a group buy for a few mwmbers on a Scott's Rods 3 Inch Exhaust Haven't heard them mention that there fuel economy has gone that bad. I think Daryn especially would be royaly pissed as he got the exhaust to make his fuel consumption better.....

[canojeckyl]

Perhaps this is the problem joe1234? I guess I was guided by the experts in their field. The 3.2L has been out for at least 4 years now, so I figured they would know what they were doing.

I have sort of got the run around (everyone always blames everyone else for the problem), but perhaps I will reapproach BE and chat again?

[QueenslandeR]

did you end up getting the aluminised steel system? what did it end up costing you?

[daryn]

Daryn just organised a group buy for a few mwmbers on a Scott's Rods 3 Inch Exhaust Haven't heard them mention that there fuel economy has gone that bad. I think Daryn especially would be royaly pissed as he got the exhaust to make his fuel consumption better.....

Currently doing consumption tests at present and around town I have averaged 12.5l to 12.8l over 3 tanks in the start stop traffic of Newcastle, too me, this is the best I have had for ages as I could easily get 14.5l around town.

Of course my expense of $750 will probably take about 3 years to make up in fuel savings but my god the truck sounds awesome and performance is better (I say that with caution as I usually rave on about my upgrades, suspension, chip etc which causes a spending spree by others).

[trouble]

I have the same as daryn, I still havn't used a full tank yet but at the moment but it looks heaps better with the exhaust fitted, looking like getting around 670ks from the tank but I will update as soon as I have the figures. Although it will not be acturate as I have aslo added a front and side bars half way through this first tank.

Thats good news daryn dropping 2Lt /100

[chick_magnet_0001]

hey daryn is that with your dps chip in aswell
12.5 is great for an auto with all shit you have on your ute( i use the term shit quite liberally)

[daryn]

hey daryn is that with your dps chip in aswell
12.5 is great for an auto with all shit you have on your ute( i use the term shit quite liberally)

Yep chip is IN running Tune 4

[chick_magnet_0001]

ahh makes me wana go and spend $1300 for chip and zorst to save 2lp100 for some reason i don't think mid 11's towing will go down to 9.5 towing in the city,unless someone wants to fund this experiment im happy to offer my ute

[daryn]

ahh makes me wana go and spend $1300 for chip and zorst to save 2lp100 for some reason i don't think mid 11's towing will go down to 9.5 towing in the city,unless someone wants to fund this experiment im happy to offer my ute

Forget the fuel saving, its the POWER you will now get, that is something else.

[Homer]

This surprises me...I was always under the impression (and still am) 3" is too big and would negate some of the potential benefits available from improved exhaust, but was pretty much all that was available 'off the shelf' so to speak. And some improvement is better than nothing...

I expected 2.75" to be close to spot on and offer better improvement again...

Maybe it is a design issue..although I don't see why economy would go UP...maybe just not go down much....interesting.

[Sloth]

I put the Scotts Rod 3" exhaust and a Chipit (tune 4 no egr blank yet) in at the same time. Economy went from 12L/100 no towing to 8.5L/100 with 500kg trailer. I'm awaiting a cable and blanking plate as i'm blowing a little black smoke at the moment so possibly a little more saving to come.

[daryn]

I forgot to add my figs are with vortex, now testing with std.

[snowman]

This surprises me...I was always under the impression (and still am) 3" is too big and would negate some of the potential benefits available from improved exhaust, but was pretty much all that was available 'off the shelf' so to speak. And some improvement is better than nothing...

I expected 2.75" to be close to spot on and offer better improvement again...

Maybe it is a design issue..although I don't see why economy would go UP...maybe just not go down much....interesting.

Homer, from all my reasearch the pipe size seemed to be important for all naturally aspirated (in your case petrol) engines. it seems once you have a turbo, the impellor provides all the resistance and you dont need a balanced backpressure downstream.

Sierra is quiet, he loves researching this stuff. h'es got a chip and new wheels, maybe we can entice him into this subject.

I put the Scotts Rod 3" exhaust and a Chipit (tune 4 no egr blank yet) in at the same time. Economy went from 12L/100 no towing to 8.5L/100 with 500kg trailer. I'm awaiting a cable and blanking plate as i'm blowing a little black smoke at the moment so possibly a little more saving to come.

those figures with an auto! Now you have my attention.

[Sloth]

Yeah i found it hard to believe as well, as i'd been playing silly buggers once the chip went in spinning the 265 cooper muddies I thought for sure i would have blown the fuel usage out the window.

Even the computer figure said 8.6 so hopefully it stays accurate. Just gotta get rid of the black smoke. Will the egr blank help this or just reduce the chip a tune?

[snowman]

probably smarter people than me to answer that but too much smoke is too much unburnt fuel.

so definately the tune will help. The egr plate stops exhaust gasses re-entering the inlet so if closed (remember it is not open all the time anyway as it has a valve) it will stop the lower oxygenated (as it has already been partially burnt) air reenetering allowing slightly more fresher air and may help a little, but i would not think it would help much - if at all.

i think the EGR plate should be done solely on carbon issue - not power.

[Joe]

Some interesting information about exhausts here. A bit of a long read and it is mainly about petrol Hondas, but most of the info is still relevent and worth the effort to at least glance over. The guy has a bit to say about exhaust size and turbos.

Pipe Sizing

We've seen quiet a few "experienced" racers tell people that a bigger exhaust is a better exhaust. Hahaha… NOT.

As discussed earlier, exhaust gas is hot. And we'd like to keep it hot throughout the exhaust system. Why? The answer is simple. Cold air is dense air, and dense air is heavy air. We don't want our engine to be pushing a heavy mass of exhaust gas out of the tailpipe. An extremely large exhaust pipe will cause a slow exhaust flow, which will in turn give the gas plenty of time to cool off en route. Overlarge piping will also allow our exhaust pulses to achieve a higher level of entropy, which will take all of our header tuning and throw it out the window, as pulses will not have the same tendency to line up as they would in a smaller pipe. Coating the entire exhaust system with an insulative material, such as header wrap or a ceramic thermal barrier coating reduces this effect somewhat, but unless you have lots of cash burning a hole in your pocket, is probably not worth the expense on a street driven car.

Unfortunately, we know of no accurate way to calculate optimal exhaust pipe diameter. This is mainly due to the random nature of an exhaust system -- things like bends or kinks in the piping, temperature fluctuations, differences in muffler design, and the lot, make selecting a pipe diameter little more than a guessing game. For engines making 250 to 350 horsepower, the generally accepted pipe diameter is 3 to 3 1/2 inches. Over that amount, you'd be best off going to 4 inches. If you have an engine making over 400 to 500 horsepower, you'd better be happy capping off the fun with a 4 inch exhaust. Ah, the drawbacks of horsepower. The best alternative here would probably be to just run open
exhaust!

Other Rules

A lot of the time, you'll hear someone talking about how much hotter the exhaust system on a turbo car gets than a naturally aspirated car. Well, if you are catching my drift so far, you'll know that this is a bunch of BS. The temperature of exhaust gas is controlled by air/fuel mixture, spark, and cam timing. Not the turbo hanging off the exhaust manifold.

When designing an exhaust system, turbocharged engines follow the same rules as naturally aspirated engines. About the only difference is that the turbo engine will require quite a bit less silencing.

[liamb]

As far as turbo engines go the exhaust gurus (race engine engineers) always seem to talk exhaust gas velocity from the turbo because thats what spins the turbo. You want the gas to escape the turbo at the speed the turbo is pushing it out. If there are obstructions ie pipe too small, poor bends, shit mufflers/ cats the gas velocity will be reduced (could also be back pressure).
I am under the impression that if the gas gets out of the turbo at the right velocity ie through the dump pipe and cat then the rest of the exhaust system could be as big as you want!. Think about the size of the universe once the gas leaves the end of the tip. When i see engines on engine dynos they just run the waste gas through huge mufflers with flange adapters to the waste side of the turbo. The last one I saw has 3.5 inch steel after the flange.

Bill

[sierra]

I'll stick my beak in, no worries!

The EGR needs to be blanked off with the Chipit and the MAP cable spliced into the system, that's the way the mapping is set up. With exhaust you should be able to use the most agressive setting. That's my understanding of it anyway.

The exhaust after a turbo needs zero back pressure to give maximum boost efficiency. The 4psi backpressure caused by the Triton muffler detunes the boost by 4psi but even worse it's losing power and fuel efficiency due to the pumping losses.
It's got a cork shoved up its arse.
The exhaust needs to be at it's biggest just after the turbo, as the exhaust gasses cool they contract and become denser and need less volume to flow.

Chipit might be getting some polished SS 3'' systems built for them at a good price in the near future?

Personally I would choose a 2.5'' system because I think it's big enough for engines this size. A 3'' pipe looks huge, especially off a dinky little turbo like the one on mine but SS should be lighter than mild steel because it's stronger, so it's not that important.

It was interesting when Justin changed my 2 channel for a 4 channel and fitted an electronic boost controller.
We ended up putting the original boost bleed valve back on because he couldn't tune out a bit of surging on my 2.5 but in the process of sorting it the boost got clipped by the ECU a few times and went into limp mode. Easy to fix with the scan gauge or lap top but it showed that dinky little turbo can easily produce 25 - 26psi also the acceleration was wild for a moment.