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I'm baaack: C34 Stagea

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I picked up a manual conversion which includes EVERYTHING I need:

- S2 RS4S gearbox with 160k km on it
- Exedy HD clutch, very new looking
- Flywheel
- Master + slave cylinders + lines
- Clutch pedal
- Manual brake pedal
- Brand new manual spigot bush
- Handbrake assembly
- Manual loom (which is apparently different to the auto one, it has an extra couple of wires coming out and going to the box I think)

I also scored some S2 interior door trims (I like them as they're a smooth looking black, as opposed to my 80s-inspired checker pattern cloth ones) and finally a radiator shroud haha.

Very excited about this package! Got to take the actual car for several drives before my mate pulled the motor and gearbox out to sell so I could verify the gearbox drives really well, clutch is great etc etc. He only wanted the shell of the Stagea for an LS swap - which in itself is going to be an awesome project!



Edited by mosquitocoils
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Over the holidays I managed to get the new turbo fitted! 

Here it is for test fitting... Hypergear ATR43, Havoc Fabrications manifold and Turbosmart Hypergate 45 (gen 4 due to space concerns as the gen 5 is slightly longer)


This also lead me into my first foray with braided lines and AN fittings. A quick trip to a well known motorsports parts shop and $250 later we have some fittings and some lines... glad I don't have to pay that again haha.


The turbo came fitted with a -4 oil feed welded into it so had to make up the corresponding line with fitting on the block. Decided to do water feed as well due to space constraints against the chassis. Picked up a new oil drain gasket too which was super handy! Here is the turbo ready to go in for the last time - 


Time to torque down the manifold in sequence - 


Put a -6 coolant fitting on the block going to the turbo and kept the OEM line that runs around the back of the motor - 


Top down view showing how close the turbo is and why I used 90 degree AN fittings -


Turbosmart gate in place and plumbed up (just for spring pressure for now) -


The final view before test starting, with intercooler piping put back together... luckily I had some spare bits and pieces to make it all fit, kinda...


I primed the turbo (CAS disconnected) until oil came out of the oil feed line... then I cranked for another 30 seconds or so and she fired up on the 2nd crank after that
! Sounds healthy and great... no major leaks but I did have to tighten my fittings a little haha.

Next step is to get the exhaust fabricated to fit between the new v-band rear housing and the cat. Probably won't be welding it myself this time haha :)

Edited by mosquitocoils
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  • 1 month later...

Got the exhaust welded up... when someone does it for a living, they make it look too easy. My mate came over and did it suuuper cheap for me which is awesome!

Started by cutting some bends and straight pipe then tacking together:



The turbo has a 5 bolt rear and came with a vband adapter... but it wasn't a standard size vband, so we cut it off and replaced with a standard 3 inch vband. Here's the finished custom dump made up:





Next up, screamer pipe:






We're going to cut the screamer a little higher so it doesn't hang so low and maybe add another little bend to throw it backwards more, but I'm happy for now.

The car sounds amazing with the new turbo... VERY loud as it's a straight through exhaust from the turbo back. Next on the cards is a varex cannon to sit right at the back so I can avoid attention late at night or around the popo etc as it's definitely way too loud to be legal!

The new loud turbo/exhaust setup has also really brought the dumb auto transmission to my attention... the way it shifts, hangs between gears etc is REALLY noticeable now... ugh, can't wait to be rid of it (in about a weeks time!)

Edited by mosquitocoils
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  • 3 weeks later...

Manual conversion time!

A few mates and I hired out a workshop for the weekend and smashed out 10 projects in 48 hours... and my Stagea's manual conversion was one of them.

I'm not going to do a full write-up as there is already a great guide on this site but I will just quickly go through the process and comment on things I found useful along the way. I took heaps of pics of things that the guide didn't cover so will throw them in too, hopefully this helps someone out one day.

Parts List:
- Gearbox (RS4S AWD)
- Clutch + pressure plate
- Manual flysheet (freshly machined)
- Manual spigot bush
- Throwout bearing (if you wanted to do it while it's apart, but mine was already almost new)
- Rear main seal (again, only if you wanted to do it while it's easy to get to)
- Brake pedal
- Clutch pedal and master cylinder
- Clutch slave cylinder
- Clutch lines + dampener loop
- Shifter
- Starter loom from the manual car (didn't use as-is but needed to use some of the electrical connectors and ran new wires)
- Shifter + square-circle bracket for the surround
- Handbrake + mounting bracket
- Interior centre console
- 4L gearbox oil of your choice

First things first - we got the car in the air (the hoist was such a big help) and removed the auto transmission in just over 3 hours. It's a pretty straightforward process, just unbolt everything you can see, leaving the crossmember til
last. The starter motor and bellhousing bolts were probably the worst part as there's not much room. 


Rear main seal is still very fresh with less than 5000km on the motor build, glad I got to see that.

The next morning we got stuck into the interior. The stock wide brake pedal, footbrake pedal and footrest had to come out which was probably the trickiest part of the whole job. Three of us alternated getting under the dash on our backsand had a go until we couldn't do any more. I removed the drivers seat early and left it out til the end of the weekend and it helped a lot. 

Dropping the steering column was very easy being only two bolts, and definitely helped reach the upper bolts holding the pedals to the firewall. There is some plastic air ducting in the way but it is easy to move gently to one side while you get your socket extension past it.

Then it was time to drill holes in the firewall for the master cylinder... definitely the SCARIEST moment of the weekend! You can see here how the holes are already pre-templated from factory but are covered over with material. So we ripped some of the padding out and drilled the holes. I drilled pilot holes first to ensure I was centred, then went bigger. From memory the big one was around a 37mm hole saw.

I didn't get many pics here but the master cylinder should just slide into your new holes... you may need to unbolt the brake booster to side it forwards in order to get some more room in the engine bay but it will all go together. 

Then it's time to cut your stagea even more... for the shifter. We cut a decent size "square" out of the top of the trans tunnel, basically leaving all 4x bolt holes intact. 

You can see how the cutout looks from under the car here and why it's important to not cut too far.

Back underneath the car now and we had to pull the auto spigot bush out. We had the right tool for it and it made it a breeze, it just popped out. This is very important as the manual spigot bush is different in size and needs to be swapped at the same time as the gearbox.

In this pic we also had the freshly-machined flywheel sitting loosely in place. You can also see the attesa line hanging free - remember this for later, you'll see why!

Now is a good time to run the clutch lines down the firewall from master - slave cylinder etc including the dampener section (if you are keeping it - I did for the same of keeping everything OEM for now, then can go to braided lines later if I decide to). Anyway here's the new Exedy clutch going on. Yes we moved the plate after realising we left it hanging down haha.


Didn't get any pics of putting the gearbox in but didn't need to do anything special to get it in. We did tilt the motor down at the back as much as we could to help align everything but that's about it. Once it was up in the air on the trans jack I drained and filled it with fresh fluid. 

Once the gearbox was in, we could verify our shifter hole was good! We also mounted the handbrake while we had the interior apart. The handbrake bracket itself come from the donor car and we pop-rivited it into my car with tonnes of huge rivets, it's pretty obvious where to place it but we also had photos of the donor car to use as reference. This is really important if anyone's looking for parts - make sure you get the mounting bracket (as the boring RS4 doesn't have one under the console). 


Shifter and handbrake mounted and looking pretty good.

At this point we hooked up the clutch lines and spent the next 3 hours trying to bleed the system and get pressure, with very sore legs...

Eventually we pulled the slave cylinder back off the gearbox and saw fluid seeping out of it but just sitting inside the boot where the clutch fork goes... so it wasn't actually a visible leak, the boot was just getting fuller and fuller... very odd. To fix this, we just pulled the cylinder apart as much as we could and sprayed it all out with brake cleaner. When we put it back together we had pressure and could bleed the system properly so must have cleared some crud out of the seal! I have noted to buy a new slave cylinder when I can. 

At this point we started the car and I could move it under it's own power in gear, how good! Although we forgot something with the 4WD system as the 4WD and ABS lights were on... 

We had plugged the attesa line into the back of the new manual gearbox, but we hadn't bled the system yet and it obviously lost the fluid that was in the line. After bleeding it (with engine running, open the bleeder nipple on the back of the gearbox with a ring spanner) once (just quickly), the 4WD lights went out.

Now for the rest of the wiring. On the manual gearbox there are 3 plugs - the two together are - 
- Front - Reverse switch - I cut and ran two wires up to the engine bay and made my own "loom"
- Rear - Neutral (don't need, leave unplugged) - will explain below

The plug by itself is the speedo, we cut the original connector on the engine bay loom side and soldered in the new connector for the manual speedo which came with the new gearbox. I think from memory it's a 4x2 plug near the fuse box. 

In the front of the engine bay near the battery are these 4x connectors used for the auto. 

Jump the first one as shown (neutral safety switch - lets you start the car). The second plug (grey) needs the black and green wires connected to the reverse switch on the new manual gearbox in order to have working reverse lights + dash warning etc. I cut this grey connector off my auto transmission to use again in the engine bay, and ran two very long wires down to the gearbox to the plug that came with the new manual gearbox, and wrapped it all in convoluted cable to tuck down behind the fuse box etc.

Then handbrake switch wiring. I cut and extended the footbrake wiring from under the dash, around to the centre console and down to the new handbrake switch. It's just one wire (black and red, up between the steering column and the stereo, sorry for potato quality photo) that needed extending. I tidied everything up once I had finished testing, the below pics just show how I figured it out haha.


The plug isn't made to click into the handbrake switch connector but it fits snugly in there with no problems so I just pushed it in.

The g sensor/g-force sensor needs to be moved as the manual centre console won't fit if it's left in place. I bent the bracket flat and used the original bolt hole to secure it near the shifter and out of the way of the cup holders. It clears the handbrake by a fair bit even though it looks close below.

Put everything back together, adjust clutch pedal free play at the stopper... then time to party!

The car drives so much differently now... it's hard to explain but now it feels like my R33 did as opposed to the fancy falcon wagon it felt like with the stock auto box! It used to almost stall after a gearshift due to maf reversion and now it just doesn't. It also sounds so much nicer going through the gears rather than hearing it flare and hang at the top of each gear hahaha. 

Edited by mosquitocoils
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3 hours ago, Dose Pipe Sutututu said:

4WD Rev Limiter Launch.mpeg not loading 😅

Hahaha man, I wish! With the big turbo on it at the moment, the stock ecu isn't enjoying all the extra airflow so I'm being pretty reserved when I do take it for test drives. Will have to wait until I have the Haltech sensors and hook them up etc before I can start playing around with the tune and make sure I'm not hurting the motor... THEN yes allllll the launches :D 

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  • 2 weeks later...

Thanks man... at this point now I'm just playing the waiting game for paychecks as all I really need is the rest of the Haltech gear.

Now that it's manual I've ordered the patch harness to suit R34 GT-T/WGNC34 so that should be here next week. That's going to make things very interesting as the MAF doesn't like the new turbo (idles perfectly smooth with MAF unplugged), so I'm hoping I can finally set it up to run mafless on the Haltech, and get it running at least solidly enough to use a daily driver for a few weeks while I sell my other car. 

From there it's a matter of ordering the wideband, the boost controller... and then eventually the flex sensor. 

I also just realised I still need to get a fuel pump as well, dammit!

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Got the Haltech patch harness in the mail this week and hooked it all up, fired up the laptop and after a bit of fiddling managed to get it to start and idle on the Haltech's RB25 base map! 

It idles SO extremely smoothly too... I'm genuinely surprised haha. The car has never run this well since owning it, but I guess since I bought it it's had a modified intake pipe so was probably confusing the MAF, whereas the Haltech base map already runs off the onboard MAP sensor, win!

Hopefully taking it out tomorrow for a few laps around town so I can start ironing out the bugs and dialing things in. 

The wideband also arrived but I haven't had a chance to hook it up yet... need to get a fat plug through the firewall on the passenger side, so I'm thinking of using the main loom grommet, but this will require me to drop the blower fan motor behind the gearbox to get enough space to push the wideband plug through. Shouldn't be difficult, just time consuming. 


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Thanks man! The wideband is definitely high on the list of priorities... although today I managed to take it out for a test spin and realised my laptop's battery only lasts for 10 minutes now. So I'm tossing up between buying a new battery for it or just buying a new cheap-ish laptop just for tuning... yet another unforeseen expense haha

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  • 2 weeks later...

Managed to get the Haltech wideband sensor hooked up. Got the CAN connector through the firewall grommet pretty easily... had to cut a small hole/slit in the grommet which took 75% of the time due to the way the ABS tower is mounted in front of it, not much room to work at all. Mounted the wideband controller in the engine bay and ran the new wideband O2 sensor across to the dump pipe. All up it only took 45 minutes, though the interior "install" still needs to be tidied up as you'll see from the pic :)



The only thing I had to do other than plug the connectors together was the wire in 12v + ground. Luckily I had already worked out which wires these were in the Stagea's ECU loom from the previous attempt at wiring the Haltech in when I had the auto transmission. I still have all the pinout info printed out and sitting in the car as well haha. So I just had to look up which wire was switched 12v and piggyback off that, and same for ground.

The software was foolproof to setup, just went in and enabled the wideband device (it already found it when I started the program, I basically just had to confirm it). Found out it's idling at about 12 AFR which explains the smell, also later figured out it was due to the Haltech base map containing very generic and very safe injector dead times. Once I found the values for stock RB25 injectors and plugged in values close to that (erring on the side of caution) I got the AFR up to about 13.7-14. 

My goal here is to gain an understanding of how each parameter of the tune affects each other, then move on to installing my 1000cc injectors, rail and FPR as that's introducing too many variables at once and if something isn't responding how I think it should, I won't know if I need to address software or hardware. 



Edited by niZmO_Man
removed duplicate photo as requested
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  • 3 weeks later...

While waiting my new boost controller and flex fuel sensor to arrive I thought I'd have a go at something I've had sitting on the shelf for a few months - halo headlights. 

Anyone can do this with pretty minimal tools and some patience (I'm still working on that last part). The longest part of this process was actually painting the housings... installing the halos was really simple. So if you're happy with the look of your headlight internals you could skip the painting altogether and save a day or so between waiting for coats to dry etc.

To start, I removed all the external stuff from the headlight, any bolts and wires that can come off.



As well as the couple of clips around the outside. Take out the bulbs to be safe.


I preheated the oven to 180° - once at temp, placed the headlight in for 5-8 minutes (I tried 5 minutes the first time but it wasn't quite enough, so another couple of minutes helped).


Once out, I laid it on a towel on a solid bench and (using an oven mitt) inserted a flathead screwdriver into a couple of spots to pry the two sections apart. It took some fiddling. I also used a (new) knife blade to help cut some of the butyl sealant in the tricky spots, although I purposely wanted to avoid doing this too much. 

It looks and feels like the edges may break but they take a lot of force before breaking... using a wider flathead lessened the chance of breaking.


I had to keep working the flathead around, using extra flathead screwdrivers, trim tools etc to stick in places to prevent it from sealing back up. 



I was left with a pretty sorry looking headlight with semi-soft nuggets of butyl around the edges... now was a good time to try and smooth them along the edges a bit (if it's still soft enough).

Inside is an extra fascia/housing which is held on with two screws so comes out easy. I chose to strip the paint off mine so I could black it out, although I left the actual headlight bulb housings alone so they remain the original chrome as I think that may be required by law. 


I soaked the plastic fascia in oven cleaner for about an hour (could be done in less but I got distracted)... it worked great! I came back and casually wiped the original paint off with no effort at all.



Gave it a good wet sand to get everything off and scuff up the plastic underneath. Then some plastic primer coats


Then I did a few coats of hi temp paint, though if I do this again I probably would use normal acrylic paint as the hi temp paint needs to be cured at many hundreds of degrees... far hotter than the plastic itself would let me heat it to. It started to melt/wilt slightly as I was trying to heat it enough to cure but I managed to get it out of the oven before any permanent damage was done.

I didn't get any pics of the painted fascia alone, but here it is when I was just starting to fit the halos. I didn't bother sanding anything as these will be pretty hidden inside the headlight housings and it looked decent anyway. 


Now on to the halos themselves!

I measured the ring sizes and found some 90mm LED rings on Amazon for the inner holes (surrounding the foglights) and some 150mm LED rings for the outer holes (surrounding the headlight bulb). I picked these as they were the cheapest 150mm rings I could find, just I could test proof-of-concept. This part required waiting around two weeks for shipping...

I drilled some tiny holes around the edges and fed some fine jewellery wire through to wrap around the rings and tied it tightly at the back. I thought it seemed a bit ghetto but apparently this is how it's done...


There isn't enough room to do the same on the outer/larger ring, but there is a perfect gap behind the fascia so I installed the LED ring directly to the headlight housing. Same deal - a couple of small holes and some wire to hold it in place.



With the rings all ready and the electrical wires poking out the back near the bulb connectors, it was time to seal them up. I gave everything a good clean on the inside before doing so.


I put the glass side of the headlight in the oven at 180° for 8 minutes by itself (until the butyl started running slightly), then the housing side into the oven for 3 minutes. Then I basically mashed them together and used a flathead to pick up any extra bits of butyl that squeezed out, trying to run it along the seam to help in sealing.


And that's everything done! 




I'm really happy with how they turned out! It'll be interesting to see how long the LEDs last. I'm stoked I learnt how it all works and next time I'd be happy to step up to something higher quality but for now these look awesome haha

Edited by mosquitocoils
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  • 4 weeks later...
  • 1 month later...

Haltech flex fuel sensor is here... along with a Walbro 460



Also after speaking with my tuner I decided to get the PRP R35 coilpack kit... Hitachi coilpacks along with the PRP bracket, loom and their custom-made short stalks so I can tuck it away under the valley cover if I ever decide to do so... 


Edited by mosquitocoils
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  • 3 weeks later...

Fuel system time

So my final parts pile consisted of:
- Billet (BPP) top feed fuel rail
- Bosch 1000cc injectors (+ loom adapters)
- Turbosmart FPR800
- A bunch of fittings/adapters to make it all work


The idea, at least for now, is to use the stock fuel lines and just adapt all these aftermarket bits to hook up to them. So even though the rail has a -8 size feed, I'm running stock 5/16 line up to the rail then using an adapter to go 5/16 -> -6 -> -8 into the rail haha. If I do go E85 then I'll need a new fuel filter as well and they generally have -6 inlet/outlets so my line setup would need to change then anyway. 

I set to work pulling all the old fuel lines off everything in the engine bay then pulling out the stock rail. The good thing about this forward facing style of manifold is that the rail was only 3 bolts and so I had it out in about a minute. Once everything was removed I put the new injector adapters into the manifold, popped the new injectors in and put the new rail on the top.

I had the thought of also tucking the injector loom underneath the manifold and it makes a huge difference aesthetically, especially with the new loom adapters you can see sticking up between each runner.

FPR getting set up with gauge

Flex fuel sensor mounted down on the chassis/bottom of the strut tower

I got to this point then realised the black paint on the manifold looked like crap... so what did I decide to do? Turned my simple single-afternoon-fuel-system-install into a week long process of stripping the paint off the manifold!


I've never liked working with paint, thinners or anything of that nature... so my knowledge was limited but now I've got a good handle on things... and I think it came out really well considering I left it bolted in place!



Now you can really see the different that tucking the loom underneath makes

Rail back on

The finished product

I went into the Haltech and changed the settings to suit and basically fired right up! Ran great while cold... didn't like being started while hot though which is the opposite of what I assumed was going to happen! I'll keep working on figuring it out and also install my fuel pump soon. 

Then it's just R35 coilpack install and then off for a tune when money (and tuner's schedule) allows... getting excited!

Edited by mosquitocoils
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