Finally found some time to install the air/water intercooler setup I'd been planning for a while.
Was a fair amount of work, but the results are as good as I could ever have hoped. It has dropped my max EGT down by 250F at least!It is very consistent and has no problem dumping the heat. It probably has substantialy more capacity than my engine requires.
Recently I also replaced the abismal factory exhaust with 2.5" mandrel from the turbo back with an Aeroturbine muffler and ported dump pipe. This modification dropped my EGT's by 150F and increased economy by 1l/100km. I'm hoping the intercooler will further increase economy.
Running 1bar boost with the factory fueling going up a 2lte killing hill (Malahat summit Vancouver Island) full throttle I cannot get the post turbo EGT's above 700F. I can do most of the mountain at 100km/h+ in overdrive!
Power is much more consistent. Before it was very evident when heat soak set in from periods of high boost. Now the power is always there, and there is more of it. I'm going to turn the fuel up with the spill control valve adjustment screw and run my max EGT's about 200F more. I expect this will make a lot more power.
The system uses a Bosch pump, 5/8" hose, a ebay 26"x7"x2" intercooler radiator, a ebay a/w intercooler with a 9"x4"x3.5" core (overall size 9.25"x6"x3.5"), 2" aluminum piping with silicone couplers, and a custom throttle inlet.
I had to modify the grill bracketry a bit to fit the intercooler radiator in the front. But all in all it fit well. I also installed a transmission oil cooler at the same time.
I removed my bullbar and fog lights to get better air flow to the intercooler radiator. I do plan on installing a winch and custom bumper which will likely reduce airflow to the intercooler radiator again, but based on the performance i've seen, I think it'll be fine now.
I HIGHLY recommend a setup like this if you have a LJ7x or KZJ7x and want to avoid head problems and be able to tow etc.
EDIT! Thought I'd follow up on the work I did here:
Following all the work I've done, I started playing around a bit with the tuning. I turned up (in) the screw on top of the fuel pump spill control valve just under half a turn. What a difference!! This made a big increase in power. At full throttle from stop, there is a little puff of black smoke to begin, but once the boost hits the truck pulls good with no black smoke!
I also increase the boost to 15psi. I wanted more but my cheap ebay MBC seems unable to hold more boost (spring weak maybe?). I used my bleed off valve on the boost sensor to reduce the boost that the ECU see's by half a psi. This keeps the computer from going into error mode from an over boost condition (factory 14.7psi limit).
For some reason, turning up the fuel this much only raised the EGT's about 100F. A small price to pay for so much more power. Booting it around town (short hard acceleration) I still only see 600F post turbine (stock would have been 1000F easy). Long periods of full throttle high boost up a mountain towing produces a maximum of 800F post turbine (stock setup this would have been way way into the danger zone and a cracked head for sure).
Pictures:
I recently bought a very clean LJ78 (1990). Would love to see more photos of your work here and hear some feedback after what looks like maybe several years post intercooler install? For some reason I cannot see the pics you posted originally here?
