CROSSOVER DELETE OPTION
For the 1HDFTE, PDI give the option of leaving the crossover in place (with the EGR valve) or a cast alloy adapter onto the inlet manifold for all of the cruiser models (80/75/79100/105).
The 1HDFTE in our HDJ79 ute has the crossover in place and has 311rwkw and 1000nm (at the wheels). I’m sure there is a point where air flow is better without the crossover but I don’t believe we are there yet.
Leaving the crossover in place is good for:
1. Legally it has to be there since the EGR valve is in the crossover – you can still stop EGR gas flow with the valve in place.
2. No more power is made by removing the crossover (for most people)
3. Smooth shutdown is possible with the crossover and butterfly in place.
4. If the engine ever runs on its own fumes (and I’ve seen two FTEs do that) then turning off the key turns off the engine.
5. If it’s the late model with electronic butterfly then it must remain plugged in to the harness.
6. If you need to pass a pit inspection the crossover must be fitted.
Our test HDJ79 cruiser fitted with the PDI Landcruiser HDJ79 Front Mount intercooler kit is putting down 300rwkw on heavy mud tyres that suck an additional 15rwkw. This allows us to get some high load testing done and also be assured that not many are going to push it harder than we do – hopefully by then we will be pushing it harder too.
The power output for the 1HDFTE in the ute and troopy was set to be 122kW (at the engine), down from 151kW in the 100 series with the factory fitted intercooler. This normally equates to 90rwkw and 110rwkw, respectively, after drivetrain power loss.
Our first released PDI Landcruiser HDJ79 Front Mount intercooler kit had a 600x240x65mm core and now we have managed to fit a 76mm thick core behind the factory grill (with a bit of slimming to the plastic), which for many who have considered the custom install to be impossible. The pipework is also 2 1/2” stainless steel for improved flow and durability.
Initial testing of the system was with an upgraded Gturbo Badboy turbo, tuning module, Safari ARMax snorkel and running standard injectors and standard airbox. Dyno testing with this configuration has resulted in a max power of 186.4kW at the wheels with a low 20psi boost. We also managed to achieve 18psi at 1550rpm with maximum torque of 668Nm at (only) 1850rpm. There is no doubt this is has to be one of the best combinations for a “mildly modified” 1HDFTE that boasts only 122kW at the engine (100rwkw) in factory form.
Our next step was to install +30% injectors. There is a step change in performance with this upgrade and needs a retune. With a few changes we managed to get 246rwkw (330hp at the wheels) and 900nm so an excellent result.
The current setup is running +70% injectors and has 311rwkw and over 1000nm. The 76mm core will make that even easier, with larger end tanks and better internal flow for high boost.
To make space for the intercooler core, the air conditioner piping has to be rerouted. The components to do this are included in the kit and the task is simple enough. Spacers are provided to space the radiator back at the top. Then the condenser has a few spacers and longer bolts to allow that to also be pushed back so that nothing touches. The condenser stays in place and flexible lines take care of the rest of the relocating. Initial testing on two different cruisers resulted in the fitter doing the regassing comment on how well the system was performing. With the installation of the core up front it continues to work really well – on a hot day it is the place to be.
With the ambient temperature 33-37deg a heavy tandem axle trailer was hitched up to increase load.
Post turbo inlet Post intercooler inlet temperatures
Normal around town driving 50-150degC 42-46degC
Highway normal driving (towing) 90-160degC 48-52degC
Max load up long hill 180degC 60degC
Under full load thats 36% more air going into the engine, which will result in a significantly improved EGT with the same fuel or add more fuel to make even more power. For those running standard injectors this is an excellent improvement. All these results were using a 500mm wide core.
We have done some more testing of the current 600mm wide core now that we can apply more load.
When working hard the turbo outlet temp was pushed to 260degC and post intercooler temps were down to 70degC – a 190degC reduction. The results below show how effective the PDI front mount is compared to top mounted configuration.
Compare this to one of the mid size current top mount setups that had turbo outlet temp of 130degC and post intercooler temp of 90degC – a 40degC reduction. We have tested the largest top mount offering and with around 150rwkw the post turbo temp was up to 190degC and the post intercooler temp was 75degC – a 115degC reduction.
Further testing with the high flow injectors has seen the intake temperatures pulled down from 250-260degC to 70 degC on a 28degC day. That is significant. A top mount under the same conditions is expected to be no better than 140degC.
If your preference is to get rid of the factory intake crossover pipe (for the EGR system) a forward facing alloy adapter off the intake manifold can be supplied.
If you’re looking here then you’ve probably worked out that our front mounts will out perform any top mount intercoolers.
Next thing is to work out what differentiates us from other front mount options.
Bonnet latch is support with solid steel brackets from lower crossmember. We do not use the intercooler to absorb the shocks of bonnet bounce.
We maximise the size of the core behind the grill opening and have been seeing results far more impressive than the smaller core should be producing. Our custom cast end tanks were designed to give us maximum width. While it is possible to make the core taller by going down further, an examination of the space will show that a 40mm portion of the extended core is blocked off from behind by the crossmember. The area that goes below the crossmember is then also blocked from the front by the lower painted panel and additionally it is unlikely to have any cooling from the air being pulled by the fan from behind. This portion of intercooler which does not see the same cooling as the upper part can have the affect of diluting the air charge with air that has not been cooled as much and therefore.
Cast end tanks are used as airflow will be smoother, especially while going between the tank and welded pipe. No welds means a stronger tank that won’t bust open along the seems at high boost.
We have chosen to go through the front panel down low as this is the simplest penetration (with an existing hole 38mm diameter) and has limited impact on the structure. The 75/79 series six cylinder radiator is mainly supported from the top mount so strength here is important.
We have seen custom installs that may look great, but no only do they go through next to the radiator mounts, they also cut away a large portion of the lower crossmember, which is a major structural component. For these custom setups, although the rear of the crossmember is kept, there is no flow through a 50mm horizontal section of the core as it is blocked from the front and the back.
Our stainless pipework is all one piece with no welding. The stainless routing goes over and points down at the turbo outlet so we can use a straight connection in silicon. This routing also works with a range of airboxes including factory, Moonlight and our soon to be released PDI airbox.
The fact that a factory grill can be modified to fit over our intercooler is great. It means you don’t have to work out what colour to paint the intercooler core or custom grill so it looks like a Landcruiser.