[Rec01L]

Hey guys,

have a long drive to work each day so ive taken my mums i30 off her hands, Diesel hatch. as a hobby ive been modifying turbo jap cars for years. mainly conversions on subarus but plenty of SR,4A,13B etc stuff too. But diesel is a new one!

So on our cars we have a pretty small front mounted intercooler, fair enough, keeps the lag down, though the rear positioning of the turbo adds enough unecessary cooler piping! The cooler gets sweet FA air flow if you look at the bumper design and i have a stack of aftermarket cores around, so i was thinking of upgrading to a proper FMIC, probably a cross path one (in/out tanks on the same side) to keep piping short. And adding a V3 STI RA automatice cooler spray i have kicking around

Ive noticed a few people excitedly aiming for rediculously (and IMHO impossible) bolt on and tune power figures, talking about changing Turbos etc.

Question is has any one gone down the path of upgrading the cooler? If so what was the verdict?

[Ultralights]

i Know exactly what your talking about, i have modified my forester in a similar way and have seen some results, but with the top mount IC. im am assuming the same principles apply to a turbo diesel.  but then again, diesel is a compression engine and relies on heat to fire the fuel air mixture..   so how would that effect efficiency and performance? or even just a simple BOV, not that a BOV gives any real performance gain, but does richen up the mixture on the subaru.

[Ultralights]

please forget my lame comment about the BOV...

[Dazzler]

please forget my lame comment about the BOV...

It didn't "Bover" me...

[2i30s]

Andrej's has done the mods you've mentioned to his diesel i30. [i think it was his car] 

[mattyallatti3013]

The inter cooler  that is on  the car dosent need to be begged or change unless ur upgrade the turbo witch there is no real point coz all ur go to get more lag in the boost and so best bets is take it to a runner and get the  turbo tuned

But yes the piping could be more direct from turbo to intercooler then engine 

Andrej's has done the mods you've mentioned to his diesel i30. [i think it was his car] 

You are right.
If i remember correctly he got some gains in acceleration above ~110kph.

[Rec01L]

The inter cooler  that is on  the car dosent need to be begged or change unless ur upgrade the turbo witch there is no real point coz all ur go to get more lag in the boost and so best bets is take it to a runner and get the  turbo tuned

But yes the piping could be more direct from turbo to intercooler then engine

Well... No.. actually. The goal is not to increase core volume, as that would indeed create a greater void to fill and a longer time off boost.
The goal is to use a different core of the same or similar internat volume but positioned in a location with better air flow and therefor better cooling potential.
I guess then the question would be would the ECU be able to accurately compensate for the increased air density by richening the fuel mixture. On any AFM or Map fitted petrol engine (particularly forced induction system) this would be a given, but on a Common rail diesel this may not necessarily be the case.

changing the turbo is an option i guess, but having looked into the system the stock garrett unit is more than up to the task of an increased boost system, the exh housing is such that it should be able to effeciently create boost in the upper 20PSI range, so any change made would be to upsize the comp housing/wheel, maybe swap for a mitsubishi TF03, or a IHI VF14/28 primary TT turbo, but then you'd lose the benefit of the VVGT turbo and introduce lag.

[Onijin]

I was thinking about this and I believe a water to air intercooler, while more expensive, would be more efficient and you wouldn't have to change much of the piping, keeping any piping induced lag to a minimum. That gap between the engine radiator in the front bumper would work well to position the radiator for the water to air intercooler. Would just need to find somewhere to mount the pump securely and should look almost factory.

Mind you, given the cost ($2000 in some cases for a water to air setup), would be better off reserving this for later on in the modding stages.

[trsc27]

I can tell you now changing the intercooler will do very little for increasing the performance of the engine, without an ecu reflash dumping in more fuel its not going to help you too much, Ive found on the track the fmic does its job more than adequately, its the radiator that needs beefing up if anything