Putting extractors and 2.5 inch exhaust on a 2000 diesel landcruiser

Submitted: Monday, Sep 02, 2013 at 12:02
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I wand to put a 2.5 inch exhaust and extractors on my 2000 non turbo, diesel landcruiser to improve fuel consumption any ideas to how much it would improve the fuel efficiency? And also anyone got any ideas on hiclones improving fuel efficiency. Any advice appreciated, thanks in advance!
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Reply By: Mikee5 - Monday, Sep 02, 2013 at 12:51

Monday, Sep 02, 2013 at 12:51
I am assuming you have the 1HZ engine. I put the Beaudesert Exhausts system on my 2003 1HZ powered wagon. It has Pacemaker headers and stainless mandrel bent pipes. The increase in power was noticeable in driving so I am guessing at about 10% increase from the original 96Kw. You can either drive faster with the extra power or drive the same as before and save fuel. I don't keep consumption records so I can't give actual numbers, but I am pleased with the improvement.
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Follow Up By: Jill K1 - Monday, Sep 02, 2013 at 12:55

Monday, Sep 02, 2013 at 12:55
Thanks mate
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Reply By: Member - cherrywipe - Monday, Sep 02, 2013 at 15:03

Monday, Sep 02, 2013 at 15:03
hi clone absolute con job,2 or 3 pieces of stainless steel placed in air intake.
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Reply By: Member - Duncan W (WA) - Monday, Sep 02, 2013 at 15:03

Monday, Sep 02, 2013 at 15:03
Jill I did the changes to my 1HZ 1999, 75 series Troopy and it went from hopelessly slow on the take off to something bordering on acceptable. Felt like I was driving like I stole it when I first had it done.

Fuel wise I wouldn't know as I never bother, mind you I rarely tow so I just want the power and don't worry so much about consumption, but I think I'm saving a bit.

Still a slow slog up hills but way better than before.

I think if you're really keen on saving fuel and want more grunt and can afford around the $6k mark I'd be looking at getting a turbo and intercooler having compared mine with the extractors against my mate who's is turbo'd.


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Reply By: Ron N - Monday, Sep 02, 2013 at 15:22

Monday, Sep 02, 2013 at 15:22
There's a lot of sneering about Hiclones as being as useless as all the other "fuel-saving" gimmicks that have no basis in scientific fact.

However, I installed a Hiclone in my turbodiesel auto HZJ80 Cruiser way back in 1992, and I measured an average of around 2-3% improvement in fuel economy. It's not huge, but it was measurable.

The Hiclone website claims 10-20% gains. This is just pure marketing BS. The gain is only small.

The principle of adding swirl to intake air in diesels is well known, and I came across this principle in 1962, when Allis Chalmers advertised the improved fuel efficiency of their newly-redesigned "Thousand Series" direct injection engines.

The new A-C diesels had a projection, termed a "mask" in A-C literature, on the back of the head of the intake valve.
This projection was specifically designed to add swirl to incoming intake air, to ensure a fine and even distribution of the diesel droplets in the combustion chamber.

Diesels fuel efficiency relies on even and very fine distribution of the fuel droplets with the incoming air. Large droplets of diesel unevenly dispersed in the fuel-air mix result in incomplete combustion. Incoming air swirl produces better results at higher RPM (2000 RPM and upwards).

As to the Hiclone results with petrol engines, the claims are somewhat spurious. A petrol engine does not rely on very fine fuel droplet distribution with the air, as diesel fuel does. Diesel fuel is a relatively slow-burning fuel, and trying to say the results are the same with petrol and diesel engines is marketing BS at its best.

The Hiclones used to be very high priced (I seem to recall about $160 or $180 in the early 1990's), but no doubt they're more reasonably priced today. For the investment of a few dollars, the Hiclone will probably gain you a few extra dollars in a diesel over a lengthy period of time - but as to major fuel savings - definitely, No.
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Follow Up By: Notso - Monday, Sep 02, 2013 at 15:29

Monday, Sep 02, 2013 at 15:29
An interesting sidelight, but my Triton 3.2 litre diesel has what they call a "Swirl Control Valve" obviously designed to give some sort of turbulence to the air but it's pretty hard to understand how the air can still be "Swirling" after its been compressed something like 16 to 1 before the fuel is injected.

I sort of thought it may be to thoroughly mix the Air and gas recirculated from the exhaust?
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Follow Up By: Ross M - Monday, Sep 02, 2013 at 19:02

Monday, Sep 02, 2013 at 19:02
All diesels have a combustion chamber and piston head features to cause an extremely high degree of swirl as the piston rises and gets to TDC. The idea of having a masked valve isn't real good as it may swirl the air a bit but also restricts flow into the cylinder and it is the cylinder which you are trying to fill. The design then does the swirl and thus mixes the incoming injected fuel.
A hiclone can only swirl before the airflow branches out into 6 and that makes the swirl somewhat altered and not happening anymore.

A petrol engine DOES rely on the same mixing of fuel and air for good flame propagation within the cylinder and it is also chamber swirled by the design. Hiclone will also restrict a petrol engine intake airflow.

2 stroke engines have a squish band design of head to induce intense turbulence so all is mixed for burning. Anything in their intakes restrict induction and power will suffer.
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Follow Up By: Ron N - Monday, Sep 02, 2013 at 19:41

Monday, Sep 02, 2013 at 19:41
Hmmm .. interesting article here ..


There's a lot at play in induction aerodynamics - nothing is ever as simple as it seems, because of the large number of factors involved in the IC engine induction and compression processes. It really keeps a lot of engineers busy over a long period of time.

Engine design has also altered in many subtle ways over the last 40 years - extremely high pressure common rail injection, piezo-electric injectors, staggered injection, developments in intake manifold design, lighter and stiffer valve trains that are more responsive, variable valve timing .. as the engineers play with one area of design, so it affects the other areas.

In the 1960's direct injection and masked valves were cutting edge - now they regarded as just stepping stones along the path of modern engine development.

Some really fascinating information in this highly technical engineering paper, below.

High-tech computational programs now play a very big part in determining optimal choices in design. Check out "3: Modelling Methodology". The complexity involved in the examination of combustion dynamics is mind-boggling.


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Follow Up By: Ron N - Monday, Sep 02, 2013 at 20:24

Monday, Sep 02, 2013 at 20:24
Here's a really good, straightforward analysis and description about understanding intake swirl in diesels - and the difference between the actual fuel combustion process, between petrol and diesel.

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Reply By: Member - Des Lexic - Monday, Sep 02, 2013 at 18:41

Monday, Sep 02, 2013 at 18:41
I have a 2000 nat aspirated 100series cruiser and I fitted a set of extractors and a 2.5"exhaust system and I found when I first drove it home I felt that he performance had improved from slug to snail. After a short period I found the improvement hard to discern.
About 12 months ago, I fitted a good quality turbo by a turbo specialist in Adelaide and the difference is amazing. It only runs a 6lb boost so puts little pressure on the big end bearings.
I tow a camper trailer and now I have the ability to overtake a vehicle without the need of a tailwind and downhill.
Yes I'm a happy camper now.
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Follow Up By: Ron N - Monday, Sep 02, 2013 at 21:50

Monday, Sep 02, 2013 at 21:50
Des, turbos put little pressure on big end bearings, because the turbo doesn't give a sharp increase in bearing loads, as a big increase in compression ratio does.

A turbo gives a boost to the entire power stroke by adding a lot more air to the combustion chamber.
More air plus more fuel = more power.
This power increase is a steady boost over the entire downwards stroke, so there's no sharply increased load on bearings.

However - the area of concern when a turbo is added, is in substantially increased combustion temperatures, due to additional fuel and extra air.

The increased combustion temperatures can lead to melted pistons and valves if the exhaust gas temperature isn't carefully monitored.

For this reason, virtually all heavy duty diesels that are turbocharged, have piston-cooling spray jets installed, that cool the underside of the piston crown.

You would be well advised (if you haven't already done so), to install a pyrometer and monitor it carefully on hot days - when travelling at high speed - or when towing.
Towing up long steady gradients is a real engine killer when a turbo is fitted, as EGT's can go through the roof on a long steady pull with a heavy load.
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Follow Up By: Ross M - Tuesday, Sep 03, 2013 at 18:57

Tuesday, Sep 03, 2013 at 18:57
Ron N
The above description is somewhat flawed.
A trubo increases the air in the cylinder and that extra air increases the compression just the same as does a higher compression increase.
There definitely IS a higher load on the bearings because that is where the torque comes from, nowhere else.

"The boost" you speak of just happens to be more pressure in the cylinder as a result of the extra air compressed and then burned with extra fuel = extra load on the bearings.

Anyone who believes a turbo doesn't cause more stress is somewhat deluded.
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Follow Up By: Ross M - Tuesday, Sep 03, 2013 at 19:00

Tuesday, Sep 03, 2013 at 19:00
Turbo not trubo, lysdexic keyboard that's my story and I'm stickin' to it
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