The R34 GTT standard intercooler arrived yesterday, as you can see from the pictures it is in almost brand new condition;



The comparisons with the standard Stagea intercooler follow, note the extra thickness and the 3 extra rows (height)




Time to measure it up, the core is 80 mm thick, compared to the standard Stagea's 65 mm. The core is 210mm wide and 225mm high (18 rows) while the standard Stagea intercooler is 210mmmm by 185mm (15 rows). This would indicate an improvement in flow of 23%, R34GTT is 206kw and Stagea is 170kw, that's a 21% improvement in power. Seems logical that Nissan would have some mathematical basis for upsizing the intercooler

The first job is the to clean out the inside, there is always some oil film in there, regardless of how new the engine is. I will be using the usual 50/50 kero and metho mix, slosh it around and empty out. Keep doing that until it comes out clean. Then flush with hot water and leave in the sun to dry out. This is what the first flush of kero/metho looked like;



And remember that's out of an R34GTT with ~30K's on it. What do you reckon the inside of your intercooler looks like?

The standard Stage mounting brackets bolt straight up to the R34GTT intercooler, as per the following picture. As do the intercooler pipes, absolutely no modifications were required;



To further improve the cooling, I want to have most of the air that goes through the LHS bumper vent go though the intercooler. Standard, around 30% of the air that goes though the vent, is ducted through the intercooler. This is the standard Stagea plastic ducting bolted onto the R34GTT intercooler. As you can see I had to redrill 1 of the three holes (RHS) and make up a spacer (strip of aluminium) for the third (top LHS).



If you look at the above picture you can see where bugs have come in through the vent in the bumper and hit the plastic above the standard duct. This was a good hint on how to configure a larger vent. Notice how the standard Stagea plastic ducting is a bit short for the extra height of the R34GTT intercooler. The new piece of ducting also has to fix that.

So the next job is to take the standard Stagea plastic intercooler ducting and add some aluminium to it to expand its dimensions to those closure to the vent. I cut a piece of alumium sheet to the right dimensions and bolted (3 X 6 mm bolts and nuts) it to the top of the ducting. Then I cut a triangular hole in the standard plastic ducting to enable the airflow trapped by the additional ducting to flow though the core.



Then it is time to fit the R34GTT intercooler and ducting into the Stagea. Since the pipework is the same as the standard cooler this is a pretty simple job, no cutting or modification required. I did the install from underneath, with the front bumper in place, this made it easier for me to measure up the ducting.

The next step is to give it a run up on the 4wd dyno and see what sort of results we get. I am anticipating a 25 to 30 rwkw increase from the intercooler and the exhaust upgrade. This is a bit more than you would expect from the parts alone, as I believe I can increase the boost with the IEBC by 0.1 bar and lean of the mixtures with the DFA to a more power friendly 12 to 1. Neither of which I can do at the moment because the standard Stagea ECU is a bit too smart. Removing the restrictions, particularly the exhaust, should mean I don't have to wind in as much correction.

Hope you will enjoy reading about this as much as I will actually doing it.


PS; this is a live post and will be updated as we go along, pictures and all.

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G'day SK,

I'll be interested in how you configure the new duct. I planned on doing the same with mine until I stuck my head under the front... Then I gave up

J

P.S. love the new pic in your signature, would look great as a poster.

Hey SK - another nice project it seems - good stuff!

Out of interest - for us Series 2 owners that already have the R34 intercooler, if we are upping stock power (exhaust etc) and boost (mines at 0.65 bar) is the only way forward a FMIC, or at conservative upgrades like this are we fine with the stock R34 intercooler?? A lot of people seem to do FMIC as a first upgrade (even my tune shop says it should be the next thing i look at), but elsewhere I read alot of people say that the R34 stockie will do if you arent going for crazy kW...???

I know what you mean about the ducting, making it from scratch is something I would leave to our race team fabricator, he is a professionsal. But I figured if I use the standard plastic duct to bolt up to the R34 GTT intercooler, then it shouldn't be too hard to make up some aluminium add ons to match the vent in the bumper. Like we do with the oil coolers on the race cars.

Yeh, the picture of the IP GTR came out OK, that was taken at Wakefield Park at the last round on the NSW Improved Production Championship. I have a few more that I will use over the next month or so.

I have done a couple of R32GTST's (RB20DET) using the standard R34GTT intercooler. It seems to work very well, the max power I have seen was 205 rwkw which is not too shabby. The only other mods on that car were a Power FC with boost control kit, 3.25" dump back exhaust (it has the standard dump) and a steel turbine wheel in the standard turbo. Obviously it has fuel supply upgrades, GTR injectors and fuel pump, but they don't add to the power in themselves.

My power target for the Stagea is 200 4wkw, so this will be a bit more than the R32GTST has. But I will be using a ball bearing hi flow RB25DET turbo which won't need as much boost to make the necessary airflow, so the turbo outlet temps should be lower. That's why it is an interesting project.

Damn I love your work sk, cant wait to see how it all goes for you

Hey SK - one more Intercooler opinion if you can...

Still unsure about going FMIC... want to keep fairly stealthy and not go to hassle of cutting into front bar etc if I can avoid it...

I have an opportunity to get an ARC sidemount intercooler for my Series 2 for several hundred dollars (direct bolt on replacement for ER34 sidemount you're installing)... it really thick... 110mm (30mm thicker than stock), and being ARC obviously of great intercooling quality...

WILL THIS SIDEMOUNT FAT ARC UNIT take care of my cooling needs up to similar power aims your aiming for with your Stag????

Great question. I was thinking the same. I want an intercooler I can install myself without too many dramas.

The ARC stuff is pretty good, there is one of their oil coolers on the car below. I see no problems with 200 4wkw through their 110 mm intercooler. I have found that thicker intercoolers don't cool quite as well as thinner (with the same volume). It has to do with amount of ambient airflow. That's why I am adding the alloy ducting to make sure it gets maximum airflow from the vent. I would suggest you look at doing the same.

PS, if I don't quite get enough cooling, say in summer, I might add a simple intercooler spray with the spray nozzle mounted into the top of the ducting.

Good stuff, I was wondering the same thing about my Trust sidemount. It's 120mm thick with very nice endtanks.

Cleaned your intercooler lately? Pictures of the flush might make you do it sooner rather than later. It makes you wonder when you hear "I put a new intercooelr and it it goes so much better", maybe just cleaning the oil film out of the current intercooler might make a difference.

i had an R34 and now have a trust sidemount IC like Jay (on an R33 GTS-t). with 0.6mm aluminium for ducting, a piece of stainless mesh to vent into the wheel arch you will get good efficiency thru these types of coolers. IMO contrary to popular belief running huge FMIC's is not the only way to skin a cat.

Should I be worried about the colour of that first flush, or would you say that would be fairly normal??

Brett

Hi Brett, nope it's fairly normal, good in fact. It only took 3 flushes to get it clean, I have seen over 10 flushes sometimes.