Rb25det S13 Weekend Toy

[IT15ON]

Hi Guys,

I have looked around on here for a while on and off, looking at GTR's I can't afford and other build threads. Time to get amongst it and start a proper build thread! I bought my S13 a good few years ago now, and did some minor bits and pieces bringing it up to scratch while learning the basics. It already had an RB25 but just with a stock turbo etc. Owning an S chassis but joining the skyline forum was mainly because I wanted to spend weeks upon weeks of my life reading on the RB25 turbo upgrade thread, which led me to purchasing a hypergear SS1PU, and the fun began from there....

• Hypergear ATR43SS1PU turbo
• Yellow jacket coilpacks
• AEM Wideband and boost guages
• 3inch metal intake to suit turbo
• High flow cat
• Removed A/C compressor
• SARD 850cc injectors

Along with fixing up radiator issues and wiring, this was my first learning project.

Around late 2013 I left my job and moved towns, which meant the S13 had to stay with a mate for a while. Using up all my annual leave I drove the car to Sydney and got a road tune done by Toshi. It was an epic trip from Tamworth with no radio or A/C but after a couple days the tune was finished. It made roughly 220rwkw on the dyno - maybe not quite what I had hoped for at the time but nonetheless was good to get it finished. This was with the ATR43SS1PU Hypergear on 98. It was the middle of December and it seemed to have a bit of wheelspin on the dyno etc - you can think of all the excuses you want - that's all it had to give.

Driving home I was very happy. It certainly had the fat midrange I wanted and felt very quick. Every now and then I went back to my hometown for a drive and entered a few motorkhanas and burnt plenty of tyres off.

While living apart I got some help from mates and added rear camber arms, welded up the diff (shimming wasn't going to be enough very worn), and put some much needed BC BR coilovers under it. It also got a nice set of 17" work wheels (albeit used) to accommodate knuckles (which still havent happened...). The car was feeling a heap better.

New wheels and it's last cruise before retirement into paddock...

Time gets away from us and eventually the car wasn't driven - collected weeds and sat in a paddock for about a year and a half. Every time you'd try to start it it would flood itself and then the fuel was stale and it all became too hard with time commitments.

In the meantime I bought myself an XR6T and got active on their forums. We modded it in the shed and it has been to Sydney Dragway plenty of times. This is my daily and keeps me pretty entertained and comfortable.

Recently I was trying to work out what to do with this poor car, and I decided it was time to bring it down here. The decision was made and I started ordering parts. A little prep work was done on the car before it was towed down here and it now lives around Newcastle. Currently it is in the process of having all the crap removed - aim is to have the car nice and reliable and working properly ready for weekend use when I want it. Drives to Eastern Creek and hillclimb events are the final aim.

I have purchased a Megasquirt and have to learn how to wire it up now. I want to integrate boost control and cooling fans which are run separately now, and have some extra features such as flex fuel, launch/flatshift and of course the usual things such as a decent cold start and IAT correction. There will also be a sensor reading harmonic balancer for trigger instead of CAS (used for sync still) to eliminate a previous megasquirt issue and eliminate belt flex etc. The ultimate goal is a car ready to run in any conditions, drive to and from tracks using either e85 or 98 depending on availability. I have a couple of knowledgeable friends who have used megasquirt in the past to help along the way.

Edited May 7, 2016 by IT15ON

[IT15ON]

A few progress notes, may help others who find themselves in my position. I'm sure some of this info is already out there but nonetheless may help others finding it here. I hope the info is correct but if not feel free to let me know - I am no expert and my car isn't running again just yet!

The loom was all removed and found it's new home on the loungeroom floor for a while. After removal I had to check a couple of wires I wasn't sure if they were still needed or not.

The first stop was the lower engine loom - which was connected below the injector sub loom. This traces to the knock sensors and a few grounds (and one other thing I can't recall) but all up will not be used for my purpose.



Next I found that a number of wires in the body loom had been terminated already (probably when this car was converted to RB25) but some were still in use as per below.


Red - constant +
Black with red trace - switched (ign) +
Brown - another +
Black with pink trace - fuel pump relay trigger

Some of these will be discarded, some will be reused to power ecu/trigger relays etc.

The dash connector (smallest connector above ) plugs in at corner of glovebox. You can see from previous pic most of the wires have been cut off and taped up. The only ones in use are:

Yellow/red - Tacho
Yellow/green - Speed
Orange - Ignition start
Blue/black - Coolant temp
Black - Ground

Next step was to mount the new sensors, MAP and flex, along with boost solenoid and ecu.





Flex sensor sourced from a wrecker ex commodore.

I have swapped to series 2 style coilpacks, with the built in ignitors. I did this to eliminate some complication and another point of potential failure down the track.



Interesting note that the mounting is slightly different for anyone planning the coilpack swap, but they do fit. Mine are currently only held by 1 bolt as sizing is different, but they are in there fine.

S1

S2

Sorting the new ecu wires into an engine bay pile and a non used or cabin pile





I have also run a fresh clean power supply via relay and fuse to power engine bay. This is mounted with radiator fan relay.



Managed to pick up a new cooler too which will be the next project, it's been hard to find any info on my current one but the new one appears to have a similar core, width of 590 vs 400 current. Same thickness and height. Hopefully there's a notable improvement (if needed).

[IT15ON]

Yesterday was a big day of wiring, with the ecu placed into final position and some more loom run. I'm happy to see the ecu will fit under the standard kick panel!

[IT15ON]

Fast forward a few weeks to the present, I have completed the engine bay loom! Just have to do the in cabin wiring now. I'm pretty happy with the look for a first time out, as long as it all functions!

Also swapped all the blue silicone to black. Small things can make a big difference. +10kw anyone?

The breadboard knows whats up

And also got to purchase a new diff from a forum member, which involved a quick trip to Gosford. Great to meet a few of you, and sorry that I had to run off. I hope to be at a few track events with the club soon! The GTR shafts and 2 way should be future proof and handle way more than my power. I wanted to do it once and for all and be able to drive the car from Newcastle to the track or drags, go hard and drive home again.

Balancer refitted with new trigger setup, hopefully eliminates belt flex and gives a nice clean signal.

The subframe should come out next weekend, diff build, then refit and it's tuning time, getting excited now.