ISUZU D-MAX AND MU-X
WORDS BY EVAN SPENCE
The Isuzu D-Max and MU-X have gained a reputation as being simple, honest, hardworking 4X4s. If you have read any of the marketing material produced by Isuzu, you would have seen the catchphrase (other than being told to go your own way) the spirit of truck. This isn’t marketing rhetoric, though, this is fact. The 3.0L turbo-diesel motor found in these four-wheel drives is, in fact, the same as the motor in ELF light-duty trucks in Japan, meaning they are massively under-stressed in a little old 4X4 ute or wagon. This also means they are capable of producing an eye-watering amount of power if you wish to turn up the wick. And let's be honest, who doesn't want (cue Jeremy Clarkson voice) more power?
To get the goss on how to make significant power safely and reliably, we sat down with Steve Etcell from Automotive Etcellence, who has tuned more Isuzu motors than we’ve had campfire roast dinners.
THE ISUZU 4JJ1 TURBO DIESEL MOTOR IS LEGENDARY FOR RELIABILITY, BUT YOU CAN MAKE BIG POWER OUT OF THEM WITH JUST A FEW MODIFICATIONS
GUIDE
REMAPPING AND ESTIMATED POWER INCREASE
Steve says a remap is going to cost about $1600, including dyno time. He says the vehicle will live on the dyno until he sees the result the customer is after. The factory ECU is tuneable, however, does have limitations. A remapped factory ECU is fine for milder gains, but for those chasing bigger numbers, Steve recommends products from ECU Shop as they offer so much scope for tuning; they aren't just a plug-in chip more of a fully tuneable module.
The factory setup produces roughly 130hp, a safe remap will round 180hp, and the sky is the limit from there. Comes down to how much you want to make, but Steve says he has seen 4JJ1 motors make up to 500hp on stock internals. That is nuts!
PERFORMANCE CHIPPING
Our industry expert said he wouldn’t recommend plug-in chip rail pressure chips for the Isuzu motor. From the tuning he has done, he says that the gains aren’t significant enough to warrant the outlay. His preference is to do a remap of the stock ECU, and if that’s not enough, the upgrade he would recommend is as mentioned supplied by a company called The ECU Shop.
“CASE STUDY: Power went from 120hp to 170hp, torque from 320nm to 508nm with 20psi of boost and a tune– everything else was 100% stock”
THE EXHAUST UPGRADES
Isuzu already fit an exhaust with 2.75” diameter tube from the factory, so installing a 3in exhaust system in its own will not see the same impressive results you would get with say a pre-DPF V8 powered LandCruiser. Sure, a mandrel-bent exhaust with larger 3in diameter will flow better, but as a stand-alone mod, I wouldn't be changing the exhaust unless it was damaged or you are really chasing big numbers. That's not to say that muffler design or routing of the exhaust can't be improved upon, but fitting an aftermarket exhaust would be low on my list of must-have mods, again, on its own.
INTERCOOLER MODS
Luckily, modern D-Max and MU-Xs have a front mount intercooler already installed from the factory. That’s not to say it can’t be improved upon, but having a front mount saves the hassle of trying to route pipes that weren’t meant to be there in the first place. The factory cooler is okay for stock duties; however, it is on the small side. There are kits for larger intercoolers available from roughly $1500. Another cheap and easy upgrade is to install a hard pipe upgrade, removing the soft rubber hoses that can expand under high levels of boost. These kits cost under $200, and I'd recommend them. Small top-mount units on older models are prone to heat soak, and Steve mentioned one of the first modifications to these engines is to install a front mount upgraded intercooler, that usually sees up to 80nm of torque gained. A worthwhile mod indeed!
INJECTORS
Injectors play a massive role with modern turbo diesel engines, and Steve suggests that larger injectors, of the plus 30 variety, will see bulk power improvements if tuned correctly. Stock injectors are happy to make up to 200hp, but it’s not ideal as they are pushed to their limit. With plus 30 injectors, a tune and an upgraded turbo, 300hp is easily achievable. You could even run plus 30 injectors on a stock motor, which will give even more gains without breaking the bank, Steve said. Plus 30 injectors will cost from $700 for the tips to $1500 or so for full replacements and are essential to making strong power figures reliably.
TURBO TIME
The stock turbo will make around 200hp; however, most are happier at 180hp as the turbo isn't working at or near its limit. There are multiple bolt-on upgrades available if you want to take things further, including wastegate style turbos but they need supporting modifications such as larger injectors and a custom tune to get the most benefit. For 99% of people, the stock turbo is adequate; however, Steve does go on to say that the most common upgrade is to an F55 turbo which sees power increase to up to the 300-350hp range with the suggested mods we've mentioned previously.
STOCK AIRBOX
Steve mentioned that while many people do upgrade the stock airbox, he's seen over 250hp made on the stock unit. It flows pretty well apparently, and is fit for purpose. However, there are still gains to be made up fitting a more substantial and better flowing unit. It's just another piece of the puzzle… still, if you are not going nuts power-wise, the stock unit can cope adequately.
FUEL PUMP
There are upgrades, but there’s already a considerable amount of flow available from the stock pump. For 99% of people, Steve tells us the stock fuel pump is more than adequate. You could play around with the internals of the pump, but Steve says the addition of a second fuel pump would make the most sense. This is for those who are looking to make massive power in the vicinity of 500hp. Still, it's not something he sees being done often, because the nature of common-rail injection systems means there is always fuel pressure at the injectors. It's not like an old- school mechanically injected engine, where you upgrade the pump to get more fuel to the injectors. So you are better off chasing power from larger injectors, not larger fuel pumps in this case.
THANKS
A massive shout out to Steve from Automotive Etcellence in Sydney, who helped with technical information for this article. Steve is a diesel-tuning guru, who has years of experience with Isuzu and pretty much every diesel engine. If you need are after more power from your diesel, or need any work done to your 4X4 give Steve a call and tell him we sent you.
For more info: aeco4x4.com.au
Phone: (02) 8834 9711
Facebook: facebook.com/autoetcellence
ISUZU D-MAX AND MU-X
The Isuzu D-Max and MU-X have gained a reputation as being simple, honest, hardworking 4X4s. If you have read any of the marketing material produced by Isuzu, you would have seen the catchphrase (other than being told to go your own way) the spirit of truck. This isn’t marketing rhetoric, though, this is fact. The 3.0L turbo-diesel motor found in these four-wheel drives is, in fact, the same as the motor in ELF light-duty trucks in Japan, meaning they are massively under-stressed in a little old 4X4 ute or wagon. This also means they are capable of producing an eye-watering amount of power if you wish to turn up the wick. And let's be honest, who doesn't want (cue Jeremy Clarkson voice) more power?
To get the goss on how to make significant power safely and reliably, we sat down with Steve Etcell from Automotive Etcellence, who has tuned more Isuzu motors than we’ve had campfire roast dinners.
GUIDE
THE ISUZU 4JJ1 TURBO DIESEL MOTOR IS LEGENDARY FOR RELIABILITY, BUT YOU CAN MAKE BIG POWER OUT OF THEM WITH JUST A FEW MODIFICATIONS
WORDS BY EVAN SPENCE
REMAPPING AND ESTIMATED POWER INCREASE
Steve says a remap is going to cost about $1600, including dyno time. He says the vehicle will live on the dyno until he sees the result the customer is after. The factory ECU is tuneable, however, does have limitations. A remapped factory ECU is fine for milder gains, but for those chasing bigger numbers, Steve recommends products from ECU Shop as they offer so much scope for tuning; they aren't just a plug-in chip more of a fully tuneable module.
The factory setup produces roughly 130hp, a safe remap will round 180hp, and the sky is the limit from there. Comes down to how much you want to make, but Steve says he has seen 4JJ1 motors make up to 500hp on stock internals. That is nuts!
PERFORMANCE CHIPPING
Our industry expert said he wouldn’t recommend plug-in chip rail pressure chips for the Isuzu motor. From the tuning he has done, he says that the gains aren’t significant enough to warrant the outlay. His preference is to do a remap of the stock ECU, and if that’s not enough, the upgrade he would recommend is as mentioned supplied by a company called The ECU Shop.
“CASE STUDY: Power went from 120hp to 170hp, torque from 320nm to 508nm with 20psi of boost and a tune– everything else was 100% stock”
THE EXHAUST UPGRADES
Isuzu already fit an exhaust with 2.75” diameter tube from the factory, so installing a 3in exhaust system in its own will not see the same impressive results you would get with say a pre-DPF V8 powered LandCruiser. Sure, a mandrel-bent exhaust with larger 3in diameter will flow better, but as a stand-alone mod, I wouldn't be changing the exhaust unless it was damaged or you are really chasing big numbers. That's not to say that muffler design or routing of the exhaust can't be improved upon, but fitting an aftermarket exhaust would be low on my list of must-have mods, again, on its own.
INTERCOOLER MODS
Luckily, modern D-Max and MU-Xs have a front mount intercooler already installed from the factory. That’s not to say it can’t be improved upon, but having a front mount saves the hassle of trying to route pipes that weren’t meant to be there in the first place. The factory cooler is okay for stock duties; however, it is on the small side. There are kits for larger intercoolers available from roughly $1500. Another cheap and easy upgrade is to install a hard pipe upgrade, removing the soft rubber hoses that can expand under high levels of boost. These kits cost under $200, and I'd recommend them. Small top-mount units on older models are prone to heat soak, and Steve mentioned one of the first modifications to these engines is to install a front mount upgraded intercooler, that usually sees up to 80nm of torque gained. A worthwhile mod indeed!
TURBO TIME
The stock turbo will make around 200hp; however, most are happier at 180hp as the turbo isn't working at or near its limit. There are multiple bolt-on upgrades available if you want to take things further, including wastegate style turbos but they need supporting modifications such as larger injectors and a custom tune to get the most benefit. For 99% of people, the stock turbo is adequate; however, Steve does go on to say that the most common upgrade is to an F55 turbo which sees power increase to up to the 300-350hp range with the suggested mods we've mentioned previously.
INJECTORS
Injectors play a massive role with modern turbo diesel engines, and Steve suggests that larger injectors, of the plus 30 variety, will see bulk power improvements if tuned correctly. Stock injectors are happy to make up to 200hp, but it’s not ideal as they are pushed to their limit. With plus 30 injectors, a tune and an upgraded turbo, 300hp is easily achievable. You could even run plus 30 injectors on a stock motor, which will give even more gains without breaking the bank, Steve said. Plus 30 injectors will cost from $700 for the tips to $1500 or so for full replacements and are essential to making strong power figures reliably.
FUEL PUMP
There are upgrades, but there’s already a considerable amount of flow available from the stock pump. For 99% of people, Steve tells us the stock fuel pump is more than adequate. You could play around with the internals of the pump, but Steve says the addition of a second fuel pump would make the most sense. This is for those who are looking to make massive power in the vicinity of 500hp. Still, it's not something he sees being done often, because the nature of common-rail injection systems means there is always fuel pressure at the injectors. It's not like an old- school mechanically injected engine, where you upgrade the pump to get more fuel to the injectors. So you are better off chasing power from larger injectors, not larger fuel pumps in this case.
STOCK AIRBOX
Steve mentioned that while many people do upgrade the stock airbox, he's seen over 250hp made on the stock unit. It flows pretty well apparently, and is fit for purpose. However, there are still gains to be made up fitting a more substantial and better flowing unit. It's just another piece of the puzzle… still, if you are not going nuts power-wise, the stock unit can cope adequately.
THANKS
A massive shout out to Steve from Automotive Etcellence in Sydney, who helped with technical information for this article. Steve is a diesel-tuning guru, who has years of experience with Isuzu and pretty much every diesel engine. If you need are after more power from your diesel, or need any work done to your 4X4 give Steve a call and tell him we sent you.
For more info: aeco4x4.com.au
Phone: (02) 8834 9711
Facebook: facebook.com/autoetcellence