This plan has come from almost two years of reading “The Forum.” It was going to be in the First Gen section as I was planning to boost my 85 GSL-SE.

Last summer my son decided he wanted to sell his 86 Base and get a motorcycle. It had new paint, decent tires and wheels, fresh brakes, upgraded exhaust, aux port inserts. It had acceptable compression, ran quite well. O’Course it a good stereo and sub So I gave him the $1000 he needed to for bike. I then spent the summer driving both cars. Hard to say which was the favorite?

In October a coolant seal let go so I knew it was time for the swap.
Over the previous year and half, I had procured many parts for SE build, but still need so much more. I decided to boost the 86 Base instead. It would take less time and money. I had a mix of S4 and S5 TII parts.

I drive mostly in a small town and short hops on the Interstate. For this, I choose to use S4 N/A rotors for the build. I wanted the low end power I was accustom to with the 6 port NA cars. I ended up with 2 S4 turbo and 3 exhaust manifolds, so sent one to BNR for the Stage 2 upgrade. Found a N332 ECU and had Rtek add the 2.1 chip. Now 4 SE 680 injectors are being serviced.

The Forum has answered most any questions I have had, a quick search and the answers appear. I’ve started to remove stuff from the car while finishing the engine build. There are a few surprises. That I would like input on, so I finally started a build thread

 

Got the twin scroll flapper removed and plugged the hole. Took a grinder to the twin scroll servo mount in hope of removing a crack. got the mount pad off but crack was still there. then got it on the engine. Put the rear seat back in that my son had removed for his sub box. Going to make a new smaller box and place it in the back corner of cargo area.

 

one of the unresolved part is the BAC. Could I use the N326. I have two N326, a N374 and even an extra one from my GSL-SE. I read an old post wear someone swapped the plastic end piece from a S4 on to a S5 BAC. sounded doable. I could put the S4 NA on The N374. Or just use the S4 NA. I'm using the NA harness with an Rtek 2.1

 

Need to rip and tear this weekend

 

 

I need suport the rear of the car, so I can drop the sub frame. Swapping out diff for an LSD. Whats the best way/ place to put the jack stand. At sometime the car was lifted and damaged the end of the frame rail. Looks like a floor lift because both ends dented the same.

 

Got a little done today. Replace all the orings in the OMP, then mounted and torqued. I annealed the copper seals, cleaned and lip tested the oil injectors. cleaned and flushed the OMP lines, then blew them out with air. still need to route the line and torque everything. Cleaned , painted, and installed lifting eyes. Cleaned alot of fasteners. Sealed and installed LIM, torqued. Torqued exhaust manifold,cleaned and install heat shield for it. Install water pump housing mount studs. Should get housing install in the morning before leaving for the long weekend. still need to clean and check the two water temp sensors.

 

Been slow progress since last update. Got the resealed OMP, cleaned and tested injectors and lines installed, than broke one of the injector lines. Luckily it was a housing line, which I had a spare. Got the water pump installed and housing sealed up. The housing had two temp sensor holes as well as a bonus hole on the front side. I’m using the NA harness, there’s only one sensor, so I plugged the extra ones. Some aftermarket gauge hole, 1/8” NPT plug took care of it.
Last two nights after work were spent trying to hook up line to the bnr stage 2 turbo. Brian changed the center section for a new piece. The coolant feed line doesn’t reach the water source. Going to make a 3/8” aluminum spacer and longer studs on the LIM to fix that. The oil drain line almost lines up with the front cover pipe. Hope the flex section doesn’t crack, but it should work.
Its not going quickly at all.
Will get some new pics next time

 

Friday morning plan; get Turbo installed and plumbed. Pull OMP back off and check the binding situation. Start on engine harness, vac lines and limited rats nest. kinda wanted to retain the hot start solenoid. I wanted to use the S5 sec. fuel rail with stock FPR and an Areomotive 30129 FPR. My plan was to bump static pressure to 43psi. Not sure if vacuum would effect the Areomotive FPR. (like the stock FPR) If it is only useful from atmospheric to boost then I'll delete the FPR soleniod and Vac lines. I have an S4 rail otherwise, and would banjo bolt in place of the stock FPR.

 

The turbo is torqued down and plumbed. Water feed spacer work out perfect. OEM heat shields is in place. Time to run the Vacuum lines and install injectors.

 

Was a productive long weekend.
Got the Flywheel installed. Had to replace one of the dowel pins, that the machine shop broke or lost. I had an old NA flywheel to rob a pin from. I had made a flywheel lock for an NA, so a little modding it is now holding. Just need to get it torqued.

I got the BAC installed. The PO of this S5 JDM UIM had filled in the idle adjust air passage groove under the BAC. Had to find a Dremal bit the right shape and carve it open again.

Oil pan is on and sealed, while there I got the motor mount brackets on. I don’t have PS or AC, and no plans to add either so the extra pulleys were tossed. Make it easier to change Water Pump.

Need to order the TB and BAC coolant hoses. I decided to keep the FPR Solinod and the Purge Valve/vent part of the emissions rack, however I only have NA rats nest. Going to build a simple small bracket for them and junk the rest.

 

The engine is now 95%. Got to pull OMP back off and check why its binding a little. Going to wait on the servicing the injectors, until less then 30 days to start up. So its ready to go in the car. got started on inspecting and shimming of LSD. Should have it back together this weekend.

 

The LSD is shimmed and back in the carrier. Set backlash at .005. Just need to check the Pattern.

I had a 3.90 LSD diff and a 4.10 open diff. Combined them to make a dirt cheap 4.10 LSD diff. Went with a .005 shim on one side and .007 on the other. Dry break away torque is 68 to 70 lb. ft. Before I pulled it apart, was only 23 lb. ft. Shall see how this works on a DD street car.

I used two extra stub shafts, two pieces of 5/16 steel plate, and welded an old impact socket to one. It made a great work stand for working on the LSD, and checking the breakaway valve. After attaching one stub, I bolted the plate to my work bench. Also spent 6 minutes and built a spanner wrench. 1 minute was just for the padded foam/tape handle.

 

Opps, Checked the FSM, and reduced the Backlash down to .0035 to .0038

 

No Pics, good camera was with the wife.
Got the LSD installed. Subframe up and torqued. Everything reconnected except new driveline. Just a couple things to disconnect and the engine will come out Friday.

 

Got the coolant sipping NA and matching trans out and pushed her outside for a good cleaning. Now back in the Man Cave. TII trans is nearly ready to go in. I opened it Saturday and all looked good expect the input gear looked worn. Not sure how to proceed. I think I'll put it in and hope it isn't too loud. Then start looking for another trans or parts for this one. I have plenty of other areas to work on, while I make up my mind on this trans.

 

Which Gear oil would be better for a worn input gear? Synthetic for its slipperiness or old school for its thickness/ sticky. I've got some Redline MT4 I could use or 75/90w

 

I had lost motivation to work on other areas of the car, with the condition my Craigslist transmission. I took the trans to a local rebuilder, he said it was done. Didn’t get much done over the four weeks since my last update. I got the Rtek installed and not much more.

Thanks “Calicrewchief”, He hooked me up with a S5 Box in good condition. It needed a crossmember I had three and all were trash. I decided to just order a new one with the stiffer mounts from Atkins. Keeping with my total Frankenstein build, I swapped the S4 tail housing from my now “parts Tranny” and into the car it went.
Mail just brought me 3 Quarts of Redline MT90, time to fill it up.

Need to fix some rust that was under the battery. As soon as that gets sealed up. The engine will be lower into place (hopefully this weekend, as next I’ll be out of town.)

 

Definitely going to follow your build. I'm doing a very similar swap. I'm swapping a JDM streetport s4 turboii motor into my 86 gxl and also using the na harness. I'm going to have the stock turbo for now though.

 

I Finally got the engine back in the car and the FMIC installed.
I picked up a “Front mount kit.” The core is quite large, should cool well. I wanted to keep it out of sight and not cut up the bumper. The only install hints were some pics on their website. Trying to keep it from hitting the under tray and curbs, I angled it like the oil cooler. It still hangs quite low, will take some trimming of the tray to get it on. The inlet pipe goes through the area where the windshield washer bottle was and outlet would just miss the battery.

I need the washer fluid option, so I’m converting the “Subzero Start” bottle. It doesn’t hold much, but with a good cleaning will work fine.
The battery side, clearance doesn’t matter as I’m relocating the battery to the spare tire well. I’m going to use an AGM battery like the one in my FB. Only 25lb and sealed, no more acid rust issues. Placement this far aft, should offset the weight of the Front Mount IC.

Past owners had let the battery do a lot of damage to the frame rails. I treated it with a rust inhibitor and painted. Sucks, a Northwest car with no impact damage or salt based rust now has a soft spot in the front corner. Lucky it’s ahead of all the suspension mount points.
I moved the horns out of airflow path, off to the side. Need to remove the horn mounts and add some baffles to plug some airways.

Engine went in quite easy. I read someone on the forum state, leave all the mounts and mount brackets off; so I removed them, then lowered the engine into place, connected to trans, then worked the mounts into position and torqued. Super quick, from engine stand to installed 20 minutes.

 

finish alot this last weekend. will post some pics soon. The engine bay is all back together. I primed the oil system, saw a little movement on the stock pressure gauge. Primed and set the base fuel pressure to #40. Zip tied the thremowax rod back, set TPS to 1volt. Turned the key and it fired off with a nice idle. I had no radiator at that time so I shut it off after about 20-30 seconds. Sweet, next I installed the radiator and coolant, started entering "boost base timing maps" got the Leading done.
So last night I tried to start it and let in warm up and check timing. No start, I must of short cycled the previous start, so now its flooded. Do I need to enter the split map before I try to start it again.

 

Got all the timing maps entered, went to start. No start, then noticed the Starting Fuel map was zero'd. Grabbed the Rtek instructions and copyed the screen shot of the cranking map. Fired right up. Worked on the idle tuning, temp installed the Wideband. Worked the idle some more. Got it decent, will continue to polish the idle. Need to get the Boost Gauge hooked up tonight and down off the work platform, for its first drive.

 

I took the TID that came with my ebay FMIC kit and modded it to except the BOV return, PCV line from the charcoal can, and the supply for the BAC. got the two small nipples from ebay and had a co-worker make on his lathe the 1 1/4" nipple. Had all 3 welded into the TID.
Bent up a bracket to support the AFM and ordered a smaller K&N filter to fit into the space under the discharge pipe.
Needed to move the Leading coils, to clear to IC piping. Just made a plate and offset them enough.
I read here on the forum that the throttle cable or cable bracket is different between the S4 and S5. Turns out I had 2 S5 brackets, so I redrilled one of them. Now there is enough slack in the cable to get the TB closed.

 

Tee'd in a boost gauge using the nipple at the flange between the UIM and LIM I had the Cruise Control servo connected to. Started the car, after warm up the idle was bouncing 1300 to 1700. Crap the idle was smooth before. Acting like I have created a vacuum leak. Gauge seemed to work fine thou. Some thing for Sunday work session. I took it for a first drive. Felt good, took it to 5k, afr were ok. 12.3 ish. Need to pull a little

 

Been struggling with a high idle. At one point thought I had it all dialed in. Then Friday morning I wanted to go for a short drive., before heading out of town. once the car had warmed up the idle started bouncing between 1350 and 1650 rpm. After the drive I did a little trouble. Shooting. TPS 1volt , sprayed around possible leak areas with carb cleaner. Nothing of note.
Took it out again today, put about 5 miles on it. Accels smoothly, seems strong. Hit 5psi by accident let off the pedal as soon as it boosted. I was in 3nd at about 3800 give her a little ahead of shifting to 4th. Oops.
The WB shows lean as I accel from 1500 to around 3000, 15 to 16 afr. Then when I hold steady throttle it drops to 12.5 to 13.1 as I cruise alone in 3nd on a small back road near my house.
When I was installing the TB a while back, I noticed the the secondary throttle plates were cracked open a little, but the adjust screw for them looked untouched. So I let it alone. Thought maybe Mazda had left it that way. Could this be acting like vacuum leak and causing my high idle, and now bouncing idle?