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Premium Member
98 RS | 98 L Wagon
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1,749 Posts
Discussion Starter · #501 ·
Okay, well...I haven't touched the coupe in a while. I spent a bunch of time and money getting my wagon prepped for some track days and have otherwise been busy. This weekend I finally made the time to get the engine separated, put dowel pins in and then re-assemble with all new hardware. While I was at it, I also removed the intake manifold and removed the engine harness. This will need to get modified / customized to work with my chassis harness.

I was lucky I only had to separate the engine slightly to get the dowel pins in and didn't need to completely remove it.



All new OEM bellhousing bolts...


Removed the IM and got the wire-harness ready for surgery. I also pulled out the stock turbo-inlet in preparation for the new RCM Group N hose.



And, finally...In other life-update news...I've been wanting a new daily driver for a while. I love my wagon, but I don't want to drive it through winter since its still very clean rust wise. Also, as I'm getting older, I'm placing more value on creature comforts like cruise control and a modern infotainment system haha. I was very close to buying a new STi, however in the end I jumped ship and ended up with a Honda. I have to say...so far its very, very good. We'll see how she is in the winter on a set of snow tires. I may miss that AWD...but then again, Michigan winters haven't been what they used to be recently. In any case, here she is...2021 Civic Type R in Boost Blue Pearl!


The plan is to not mod it. We'll see how that goes! I've already removed the pin-strip on the lips and have a set of winter wheels coming for it...Other than a set of different summer wheels, that should be all it needs for me to be happy!
 

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'99 2.5RS
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274 Posts
Congrats on the CTR! I had one for a bit and I loved every moment. One of the best all around cars on the market today. Even the mpg is crazy good. If you ever mod it, let me know. I still have a few bnib parts for it 😂.
 

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98 RS | 98 L Wagon
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1,749 Posts
Discussion Starter · #504 ·
Quarterly update? My work on the coupe goes in waves. I was dormant for a while, but recently there has been a flurry of activity. Here's a list of things completed since the last update:

  • Wired the surge tank pump
  • Made the transmission / small engine-bay harness
  • Made the engine harness
  • Reinstalled the intake manifold
  • Installed IAT
  • Mounted Flex sensor / fuel pressure sender
  • Mounted EBCS
  • Mounted Haltech TC8 module and fit the EGT thermocouple wires to length
  • Installed the AOS
  • Installed turbo-inlet
  • Made fuel lines to the engine
My plans changed with the engine wire harness. At first my plan was to take the stock engine harness, tear it down, re-route what I could and extend what I couldnt. I got as far as completely disassembling the engine harness, cutting each circuit to each connector and basically realized half the harness was long enough and half wasnt. I didn't like the of splicing to extend wires, so I started to plan on making half the harness new and using half the OEM harness. This didn't sit right with me, so I just bit the bullet and built an entirely new motorsports style engine harness.

A collection of OEM connectors from iWire and harnessing materials from ProWire. Being able to buy new connectors is so nice...Very thankful for that service.



I built the harness from the engine to the firewall. This way I could more easily get the lengths and runs just how I wanted before doing final layup. Here's all the connectors terminated before layup. I used DR-25 heat-shrink again for this harness as well as labels for each connector.


Heres some from the layup process. This took a lot of back and forth fitting onto the engine to get the the lengths and positions of each branch correct. Eventually, a harness emerged.






I'm waiting to shrink the last boot onto the bulkhead connector after I've confirmed everything is functional. So far everything tested is good.

Moving on...Some harness related things that happened along the way...I purchased the rest of my sensor package. I got a Continental Flex fuel sensor and the fittings to mount up the fuel pressure transducer. I also purchased a super fast response motorsports IAT sensor made by KA Sensors. And finally, a MAC 3 port EBCS. For the Flex sensor and EBCS I got some nice billet mounts from Raceart.



The KA IAT Sensor offers super fast response. And conveniently, its M12x1.50 which is the same thread size as the OEM V9 STi / Spec C IAT sensor. So, it thread right in. Voila.


I mounted the Haltech thermocouple module in front of the drivers side tub. This thing isn't waterproof, so I'm a little worried about the position here but there wasn't really anywhere else it fit nicely. I will cover most of those holes and perhaps put some thing to seal the unused connections. Also, that bulky chincy looking connector on top will get replaced with a sealed 90* Raychem boot. I also cut and terminated all 4 EGT thermocouples down to size and did some cable management.



And this is how she sits now. AOS installed. Harness installed. Fuel lines ran. Turbo inlet installed. Only a few things left before I can fire this thing up for the first time!
 

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98 RS | 98 L Wagon
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1,749 Posts
Discussion Starter · #509 ·
Badass update! Getting close.
Keep up the good work.
Thanks man, I appreciate it!

WOW, that harness is amazing. amazing amazing.

how many hours do you guestimate you put into it?
It's hard to keep track. Probably something like 20-30 hours? Populating the big multiconductor bulkhead connectors is a very time consuming process. Just that alone took me something like 8 hours.

Holy shit - the harness is unreal - looks like it's assembled better than the factory harness. Outstanding work man!
Thanks, I really appreciate it. It's definitely nicer than OEM :LOL:

IAT is going to heatsoak there, I'd move it pre-TB
This is a topic I love to debate! In my professional opinion, the IAT should be placed as close to the intake port as reasonably possible. You want to be estimating the density of the charge entering the combustion chamber for the speed density model to be most accurate. There can be real temperature changes across the path between post-intercooler and intake port. This is especially problematic at part throttle. This is why you'll almost always see OEM's putting the IAT sensor in the intake plenum (most commonly it's a combination TMAP sensor).

Can it be done successfully with IAT in the intercooler? Sure...You just end up baking in a bunch of error into the VE calibration. This means if you later want to change your Lambda target or make a change to the fuel system hardware you end up needing to make corrections to the VE map.

In any case, The sensor I chose is super fast response which should make it less sensitive to heat-soaking. And I trust Subaru chose a good position in the plenum for the sensor. :)
 

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99 WRB GC V9 Spec C RA recce
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993 Posts
in general I agree with you, and I tried it for years, but heat soaked hot starts are awful, so after years of struggle I will be moving mine to preTB
 

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98 RS | 98 L Wagon
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1,749 Posts
Discussion Starter · #512 ·
Short update...

First of all...I was able to get the engine to crank and begin testing the some of the engine wiring and all the inputs and outputs. The engine builds oil pressure, the cam and crank signals looked perfect, the ECU is syncing and showing engine speed, the injectors are firing (no fuel yet), boost controller works, etc. etc. One thing was that I did not have spark...I tested all 4 coils, check the signal with an oscilloscope, quadruple checked power and grounds. In the end, I had 4 bad ignition coils. Womp. Anyway, I have verified spark and I'm very close now to being able to start it!

I originally wanted to put the fuel filter in the engine bay, as factory. And maybe even use an OEM filter setup, but it didn't work with the packaging I wanted for the flex sensor. So, I decided to put an aftermarket filter in the back near the surge tank. Picked up this Radium setup and made a new line, used the previous feed line to connect to the filter outlet.



I wrapped and installed the RCM Downpipe. I only wrapped it to try to keep engine bay heat down. I also have a turbo blanket and heat-shield on the way. The downpipe itself was a bitch to mount. The hole spacing on the flange is very tight with the studs, so it required a LOT of finagling to get to mate. But, I got it.



And finally, some functional bling. The thermocouple connectors seemed easily shaken loose from the amplifier. Even just working around engine bay they would get disturbed. Luckily someone makes this little doo-dad. Problem solved.


I've got a bunch more parts on the way. I need to fill it with fuel and calibrate the fuel level sensor. Fill the gear box up. Finish some brake lines...many other odds and ends...We're getting there.
 

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98 RS | 98 L Wagon
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1,749 Posts
Discussion Starter · #515 ·
Alright, another update...Where to begin? Not sure I feel like typing a bunch out. Basically, I completed:

  • Thermal management - turbo blanket and modified heat shield
  • Power steering lines and reservoir
  • Installed bias knob / cable
  • Brake lines
  • Cooling system - Radiator, fan, hoses, overflow, head tank
  • Intake - filter / adapter
  • Intercooler
Brakes are bled. Engine is complete. Trans and diff have fluid. I'm hopeful to start it this weekend...at which point it should technically be a running / driving car. Onto some photos!







 

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Premium Member
98 RS | 98 L Wagon
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1,749 Posts
Discussion Starter · #518 ·
making a lot of progress! That is a piece of art in your engine bay. ♥
Beautiful! Amazing build. Super clean.
Thanks guys, I really appreciate it!

I flocked my dash over the weekend and reassembled it last night. Pretty stoked how this all came together.



 

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98 RS | 98 L Wagon
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1,749 Posts
Discussion Starter · #520 ·
Have your started it yet!?? I'm on the edge of my seat here!
Indeed I have. I got it kinda fired up on Saturday, however it first only fired on cylinder 2 and then eventually cylinder 4 as well. The 1/3 bank was not firing at all. Checked coils, checked injection wiring - Everything was good. I immediately thought it could be clogged or bad injectors - you never know with these import engines that have sat around for god knows how many years. Turns out I was right...



One was really dirty, the other not so much. The dirty one also didn't actuate when I powered it manually. I had to cycle it a few times before it came to life. I cleaned them both, put it back together and woudln't yah know it....All 4 cylinders. I proceeded to fill up the cooling system and let it warm up a bit - put it in gear on the jack stands to make sure the drivetrain was happy. All seemed good, so I took it on it's first self powered trip out of the garage. First time in going-on 7 years!


So anyways...yep, it's a car. I gotta get my bearings and figure out what to do next. I might replace these injectors just cuz.

 
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