Car #2 – 1990 Nissan 240SX better known as S13
Unfortunately I have very few pictures of this car. But my friend Matt and I put a lot of work into this baby. And it turned out to be an amazing car that was a ton of fun to drive. But I made 2 fatal flaws when building it that I never rectified and in the end, they were the reasons I sold it.
The story of this cars begins on ebay, then leads us to Portland, Oregon. My friend Matt had a Nissan S13 coupe (not hatch back) that he had done the typical SR20DET swap on. I drove it at a couple autocrosses and on the street a few times and loved it. So, being the way I am, I decided I wanted a car as fun to drive as his only done differently since I hated to be one of those SR20DET nut swingers. After some research I decided I wanted the CA18DET engine. It’s a smaller higher revving engine than the SR20DET. The CA18DET was an older design and is more similar in design to the RB series than it is to the SR’s. Supposedly the CA18DET is 40 lbs lighter than the SR20DET which is about 40 lbs lighter than the stock KA24 engine. The valve train design (being like the RB engines) does not use rockers. It has the camshafts act directly on the valves. Well, as directly as it gets anyway. So I figured that would likely give it a better sound than the SR. Oh, how I hate the noise that comes out of the SR20DET. The CA18DET only makes like 175 HP stock and has a much smaller Garrett T25 turbo than the one the SR20DET comes with. But it’s a turbo and I know how to squeeze some power out of them. So a lighter, higher revving engine with almost as much power, but with a nice strong cast iron block won. I found a CA18DET front clip with a rear sub frame on ebay for about $1,800. Sounded good to me. I was the only bidder (yet another reason I like slightly more obscure automotive items) and had it shipped to my house.
I had been trying to find a car to go with my front clip for about 2 months and was almost ready to give up. It seemed I hit the market a bit late and people were trying to sell rust buckets for $4,000. To make things tougher, I was set on having a hatch back, no sunroof, and wanted black. Finally, I found this one on Autotrader for a decent price. Portland is where I bought my AE86 (hachi roku) from so I knew the area could be a source for some VERY rust free vehicles. And the car scene there seemed a bit more oblivious to little gems like this and the hachi than other cities with bigger car scenes that could also produce rust free vehicles. After emailing back and forth with the guy we decided on a delivery time and place and I bought plane tickets for Matt and I to fly there and pick it up.
Upon first sight, I was afraid I got hosed. It had the most horrendous side skirts on it that were attached with rusty sheet metal screws. And I was not a big fan of this aftermarket rear spoiler / wing thing. The hood had been pulled off some junk yard car and repainted. But due to some damage on it, you could see the red paint under the black. But other than that it appeared clean so I figured I would deal with the side skirts, wing, and hood. The engine bay wasn’t clean so monsters could have been hidden under the grime, but since I already had the front clip waiting for it at home, I was only concerned with making it home. Luckily my front clip also had a usable hood on it as well.
So after a rather uneventful drive home in the car, the very next day I took it in to get inspected for registration and it passed so we immediately began tearing it apart to prepare it for the clip. The rear sub frame that came with my clip seemed to be in much better shape than the stock one. So rather than using parts from it, I swapped in the full sub frame with viscous limited slip differential (upgrade from the stock open diff), larger anti-roll bar, and much better bushings. The engine dropped in rather easily. Matt is a huge fan of OEM look, and I must admit although I am not as much a fan as he is, I do like it when things look like the factory meant them to be there. So that required us to do a lot of extra work on the wiring harness. But we got it done and it looked great.
I bought some other parts for it, including a nice head unit and some good replacements for the stock speakers, and drove it this way for maybe 3 or 4 months. Then one day driving home from work I had a smoke cloud following me everywhere I went. I was pretty sure my turbo took a dump. So I parked it and went down to dad’s shop. I knew he had a few hundred of the T25 turbos in the same size as what this car used. Turns out though that the oil and water connections were all different. Dad’s were standard, and of course the stock Nissan stuff was metric. Then I noticed he had a nice new GT28R ball bearing turbo laying there that I had seen a few months ago. So since it was obviously not being used I asked if I could have it and being the rad dad he is, said yes. Turns out that by avoiding an extra few hours work, I gained probably 100 hours of work. The compressor housing was too big to fit under the stock exhaust manifold. So I drew one up and had Matt machine me a spacer. Then the intake was a 2 bolt flange rather than the stock hose sleeve. So I had Matt machine me an adapter for that as well. Then because the whole thing was spaced slightly different, the hard lines for the oil drain didn’t line up quite right. Also, due to the higher power potential of the bigger turbo, I knew the stock CA18DET MAF sensor wasn’t going to cut it. So rather than paying $300 for a Z32 MAF, I opted for a larger Q45 MAF that ran about $70. Turns out the Q45 one is so oversized it lack the resolution necessary to run very smoothly at low RPM on a tiny little 1.8L engine. After I finally got that all figured out I figured I had won and I was going to go out and kick some ass racing people. Not so much, the dumb thing would start, but I couldn’t even drive it out of the garage without the engine dying.
So after hours of internet research and even more hours making sure everything was hooked up right, I decided the solution was to reprogram my ECU. I am not a super techno geek, so prior to this little endeavor, I wasn’t even sure what an EPROM was. So I took the plunge and bought an EPROM programming tool and a supply of the related chips. There was some programs I found online that gave an OK starting point (or so I thought) for settings to change and program to the chip. I pulled the stock chip out and had Matt (because his hands are way more steady than mine) solder in a ZIF socket because I could tell early on that this was going to take more than one try. So using the tools the internet gave me, I programmed my first chip. I had no idea if I had done anything right. So after reinstalling the ECU with my first program attempt on it, I turn the key, and…
Damn thing didn’t even start. So was the ZIF socket installed well enough? Did I screw up the program? Did I plug everything in? Did I even use the right kind of EPROM? Was the info on the internet just put there to mess me up? I had no idea. So after hours of checking everything, I decided I would try another chip with a modified program on it. I installed it. And BAM, the car started. AND I was able to drive down the street. I was stoked. Finally, progress. I had bought (10) 128K EPROM chips for this job. Yes, that’s right, the CA18DET uses a 128K EPROM. Modern cars I think are up to like a gigabyte chip or something silly. Once all 10 chips had been used and I was not happy with the program I had to do some research to find out if I could reuse them or if I had to buy more. Turns out the type I was using has a window on it that makes it so UV light can erase them for re-use. Rather than buy a device designed for that purpose, I just set them all out on the BBQ grill on the back porch. After sitting there for a day, they all seemed to be ready for action. I tried maybe 4 or 5 more and still not happy with it, I contacted my friend in Japan. I knew he had experience tuning Nissans at his shop in Tokyo. Well, it turned out he pretty much only tuned RB’s and SR’s. But he had a friend with CA18DET experience. about a week later I got a file from him that was made by his friend. I opened it up in the program I was using that tells you what everything is set to and it had some very unusual settings. But since I had no success so far I figured I would give it a shot. Catch was, Atsushi (my friend in Japan) told me I had to up my fuel pressure. I forget what pressure he told me to use now, but needless to say, it required an upgraded fuel pressure regulator. And just for good measure, I bought upgraded fuel injectors and an ARC side mount intercooler from Atsushi while I was at it.
Yes, before I figured out how to get the car running, I was already doing more upgrades. I installed it all and set fuel pressure to the given amount and WOOHOO, my baby was back to life. And actually running pretty stinking good. After a couple hard pulls down the street I decided I better take it kind of easy until I could get it on a dyno and check A/F ratios. Besides that, while it did feel good, I could feel something wasn’t quite right. I took it down to my buddy Full Size’s shop. He worked at Utah Imports. They had a smoke machine. So we threw it on there to make sure everything was sealed up right. I knew I had low compression on a couple of cylinders, but it was always like that. It wasn’t that low. Well, the smoke machine found a HUGE leak. Turns out ARC (I thought they would know better) tapped one of the mounting holes all the way through the boss and into the core. And I just happened to not be using that mounting hole since the bumper some time in its past life had taken some damage. So I threw some goop on the bolt and plugged up the hole and holy cow, what a difference. Time for some dyno time.
I put it on the Cobb Tuning dyno. This was before I worked for Cobb and they were still in a building they were sharing with Modern Garage. So the dyno was at Modern Garage. It’s an AWD Mustang dyno. The car was running really rich, but sounded healthy. So I had Christian do some tuning on the Greddy Profec B Spec 2 boost controller so I could have a high and low boost setting so I could pretend I was worried about economy. After about an hour on the dyno, I came away with 2 boost settings. 15 psi and 12 psi. The 15 psi setting made 302.5 HP @ 6200 RPM and 302.9 lb-ft @ 4800 RPM. The 12 psi setting made 279.1 HP @ 6600 RPM and 254.9 lb-ft @ 5200 RPM. So both settings had the same power band, it was just shifted a little.
It was running about 10.2:1 A/F which is insanely rich, but plenty safe. So while I could have turned down the fuel pressure and got it to run a bit better, once I saw those numbers on the dyno, I figured I would leave well enough alone. I didn’t want to mess with a good thing.
Now to my critical build mistakes. First, I didn’t install the A/C. This was supposed to be a track/autocross/daily driver and I figured A/C wasn’t crucial. I was wrong. That car got blistering hot and I didn’t like driving it on hot days. But I also hated driving it on rainy days due to the power levels making it too easy to drift. Drifting is fun when that’s what you want to do. But not when you are just trying to get up a freeway on-ramp. Second critical mistake was not installing the power steering. I had left it off my hachi roku and loved it on that car so I figured I would save the weight and try it on this car. It sucked. Especially on track. It would pull huge G numbers in the corners, but it turns out the car wasn’t limited by the tires or suspension. It was limited by the grip strength of my hand.
I never took it to a drag strip. But I am sure it was probably low 13’s if not better. At this altitude (4500 ft) Matt ran a 14.1 IIRC and my car was about a car length per gear faster when we would race side by side. Actually it was probably a bit more than a car length per gear. This car weighed a little under 2,400 lbs when I corner balanced it. So it was a pretty quick car. Not built for drag obviously, but locally, it would have done just fine. Not much on the street could keep up with it. In fact, it never lost. But I never came across truly fast cars to compare it against. Just the random Porsche or Corvette.
OK, now for the mod list:
- CA18DET from a 1989 Nissan 180SX
- Megan Racing Turbo Elbow
- Megan Racing Cat-Back
- Greddy Downpipe
- Greddy Profec B Spec 2 Boost Controller
- Greddy Full Auto Turbo Timer
- Garrett GT28R Ball Bearing Turbo
- Custom tuned ECU
- AFE Air Filter
- Custom made billet air filter adapter for a Q45 MAF
- Infinity Q45 MAF (don’t do it, it’s a trick)
- 444cc injectors (I believe from a RB20DET)
- ARC side mount intercooler
- Nismo adjustable Fuel Pressure Regulator
- Under Hood Fuel Pressure Gauge
- Kosei K1 Racing Wheels in 16×8.5 Rear and 16×7.5 Front
- Yokohama AVS ES100 Tires. 245 Rear and 225 Front
- JDM Rear Anti-Roll Bar (bigger than USDM)
- JDM Rear Differential (different ratio than USDM and also has VLSD)
- JDM Front Bumper (has a hole in one side for intercooler)
- Rear Subframe Collars
- KSport Coilovers (with custom spring rates I chose)
- KSport Camber Plates (front) and Pillow Mounts (rear)
- Custom Billet Aluminum Turbo Intake Adapter
- Custom Billet Aluminum Turbo Mounting Spacer
- Pioneer Premier OLED Screen Head Unit
- Strut Tower Bars (front and rear, no name junk ones)
- Hawk HPS Brake Pads
- Braided Stainless Brake Lines.
- ATE Super Blue Brake Fluid
This story unfortunately has a somewhat bitter-sweet ending. Since I didn’t drive it as much as I though it deserved, I decided to sell it to pay some bills and hopefully have enough left over to finish my insane hachi roku project that started a year before I even thought about an S13. Since I still loved the car and I had put so much time and love into the thing I was asking a pretty high price for a salvage titled project car. A Japanese college student that I knew that was here for a couple of years to finish up his degree came to look at it for his daily driver for the couple of years he was going to be a student here. He knew I was asking too much and being a dick I didn’t budge on price. After another month he came back and bought it for my asking price since in that time he never found a car he liked better. He drove the shit out of it for the time he was here and honestly I don’t think he ever did any maintenance on it. When he left he ended up just giving it to Full Size Alan and he fixed a bunch of stuff on it that had gone into disrepair while Nori owned it. Then Alan pilfered some parts off it and tried selling it but I don’t know if he ever found a buyer willing to pay what he wanted for it. So the car just ended up getting cannibalized to help Full Size’s project car. And as far as I know it is in some junk yard now.