AGP2006 SAU VIC Nissan Skyline GTS4 Turbo Car Club

Nissan Skyline R32 GTs-4 Turbo AWD Intercooler Upgrade

Nissan Skyline HR32 GTS4 Intercooler Upgrade Modification by fitting FMIC from Skyline GTR


Skyline HR32 GTS4 AWD Turbo


RB20DET Single Turbo 2.0  Ltr 4 Speed Automatic  AWD HICAS

First Intake Modification.

This is the first modification of many I did to my Skyline over ten years of enjoyable ownership. The inter-cooler was the easiest issue to overcome with some simple piping.
Of course this was not good enough for long, as I really wanted to get rid of that long pipe and reduce lag and heat soak!
See what i did here to totally modify the Nissan Skyline GTS4 Intake Manifold to front entry reducing the air passage and throttle response!

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The Nissan Skyline HR32 GTS 4 AWD seems very naked about now with everything removed to explore the options of the Skyline GTR standard Front Mount Inter-Cooler (FMIC) upgrade.

The front mounted Nissan Skyline GTR HR33 Intercooler fitted perfectly into the frontal radiator area with a bit of massaging with a saw into the plastic front clip.

There is actually a fair amount of flow up under the standard bumper bar to the top of the inter-cooler as well.

That is why I have fixed on a extended piece of flat Aluminum to ensure air goes though the FMIC at the top instead of taking the easy path straight over it.


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I had been to quite a few places to try to get some “expert” advice on what I should do to inter-cool the car for proposed higher boost as I want to break into the 12’s.

The advice from one shop was to makeup a hybrid I/C from two smaller coolers and come in the top and out the bottom and back to the original piping in the engine bay.

This sounded OK and the price seemed reasonable around $1800 for the work involved.

BUT every time I called in to see them they were always too busy to do anything this week!

So another shop come up with a second hand cooler from a truck core and piping at a great price under a grand so seemed to be a better idea. BUT they were very busy also!

SO what to do…Then I visited John and saw the GTR¬†cooler and made an offer of $600.
I kicked my self two weeks later when I¬†saw another one fully polished and¬†detailed for $900. This Inter-cooler was actually supplied by a¬†chance visit to see John Martin at¬† OrienT¬†Express who had originally sold me the car in ’97.

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The original holes for the two inter-cooler pipes. The rear hole
usually being for the turbo outlet.

In this mod it will be the front hole used for the turbo outlet to allow clearance for the 
Modified Nissan Skyline Air Flow Meter (AFM )

– (more about the modified AFM here)

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The Stainless Steel pipes and straight sections I bought locally at about $18 for the bends and $20 for a metre length.

The hose I bought at a good rate from the scrap bin. They made up for it on the fancy clamps which cost about $7 each though they were worth every cent.


I am sick of the standard type screwdriver fastened clamps as they never seem to hold for long and always come loose.
These clamps do not!

Well not until you are in the middle of nowhere anyway;-)



Like on the return trip from Adelaide¬†after Martin Donnan Dyno’s the car!¬†Lucky the¬†clamp was accessible through the front intake
and did not cause too much drama except when returning to Melbourne on the outskirts and I had a drag with a Commodore.

The boost must have¬†been leaking previously when Martin Dyno’d it¬†and set it at 15PSI.¬† By the way it accelerated and then started¬†detonating I figured it must be way higher and¬†when I checked it on the boost gauge¬† hidden¬†under the Ashtray it was over twenty PSI!


Tucked tight under the FMIC outlet pipes is the high volume oil cooler and 12v fan for those days when the oil temps may get a bit higher than normal.




The airflow through the front clip side hole also forces down through it at speed adding to the cooling effect. This view also shows the custom Oil Cooler system that I have engineered to reduce engine oil temperatures for the drags and mainly circuit track days.




Having driven the Skyline GTs-4 for a few weeks now with the upgraded GT-R FMIC,¬†the ECU seems to have retuned the Air-Fuel ratio’s to be a¬†bit leaner and the power has increased with
the boost still set at 10psi.

The modified fuel rail and RX7 Fuel Injectors will certainly be able to cope with any boost increase in the future.

It certainly has made a difference that I was able to detect while driving out of the garage the first time after fitment! The revs seemed to build quicker and the response to the throttle was much better.




On the passengers side where the original Side guard mounted Intercooler was now holds a securely mounted air  conditioning condenser that has a huge
volume and high flow though for the 
modified Nissan Auto Trans ( – More Here
to keep the temperatures down when stalling up the 2800RPM Soderstrom Torque converter at the drags.


This massive cooler also gets air coming in the front clip passenger side entrance duct but is also assisted by two 12vDC Computer fans for good measure while stationary at the drags.

After spirited driving on the turbo a bit I can touch the outlet
side where its very cold while the inlet side is quite hot as you would expect.

From experience the temperatures from the
turbo can be up to 200’c in extreme circumstances so any reduction makes a difference!




By the way anybody out there with an Auto Nissan Skyline GTS, or most Turbo Auto’s¬†its not so much as a blow off valve on the¬†intake piping as a BYPASS VALVE!!

The function of this item is to open immediately you push the throttle to bypass air to get everything happening quickly.

If you don’t believe me¬†just pinch the vac line (or put in a tap as I¬†did) and see how much more slower you get off¬†the line! Its an Automatic remember and you don’t¬†take your foot of the throttle to change gears¬†like manual cars do (mostly;-) where you need¬†to vent boost from slowing the turbo!



blow off valve on the intake piping as a BYPASS VALVE!!