"Stephen Rivers" (stephenrivers)
10/17/2019 at 08:05 • Filed to: WRX, Subaru, STI, RallyCross, Turbo, Rally, boxer, EJ20, Rebuild, Build, Tune, Tuner | 13 | 11 |
Rebuilding a tuned bugeye through blood sweat and tears
Lesson 2 : Know what you’re buying.
When you build a tuner car you have to think about your goals before you do so. What type of power do you want to make? How long do you want that power to last? Anyone can get high horsepower numbers on a dyno once or twice. It’s getting that engine and power to last day after day, month after month, year after year that counts to the budget minded builder.
After the horrid lesson 1 about this car I learned to watch out for it’s health like a paranoid parent sure that their child would harm themselves if not looked over every moment of every day. Almost a year of fantastic driving later I noticed 2 problems. 1. I was getting white smoke from the exhaust occasionally and 2. The car was running a bit lean, even in boost, a big no-no for a turbo or supercharged car. These problems led me down the most ridiculous rabbit hole of automotive conundrums one can imagine. Come down it with me will you?
Solving the smoke turns into a monster with many heads
Smoke can mean many things but in my case it ended up being my turbo showing signs the end was near. The bearings were leaking a little oil which would be heated up and burned in the exhaust causing the puffs. Sourcing something similar wasn’t too hard but did cost quite a bit. The problem is that with a different turbo comes the need for a new tune. The car can’t make that big of an adjustment on its own and if you read part 1 you’ll remember the nearest tuner was 5+ hours away now, so we turned to the local community for help and found a guy who could work on our car here.
The leak that would stop the whole car.
A few days of trying to dial in the new turbo he notices the lean issue I mentioned and suggested replacing the O2 sensor as the car seemed to be a bit more stable when he unplugged it. We replaced it and the MAF sensor in an effort to get cleaner readings and an easier to tune car. Ultimately more was needed though, as the tune was almost finished the tuner noticed a serious issue. Under boost the car would reach 5,000 rpm and the clutch would begin to slip and ultimately let go as the real power would come on. This meant replacing the clutch, throw out bearing, flywheel, and most importantly and expensively the pressure plate.
The clutch going out was especially frustrating. It was the latest in what you now know were multiple issues. The problems didn’t let up. When we brought the car home from the tuner to put the new clutch in, the radiator sprang a leak. So we upgraded it along with the clutch. That’s only another $1000 thanks to our own ability to do most of the work. Due to our budget though a couple weeks had passed and our tuner was now on deployment in Afghanistan.
So now with no tuner within 3 hours, I turned to the internet. Subaru enthusiasts have a great community online that shares more tuning information that you could need but finding that info can be tricky so the car again sat for weeks only moving to be driven around the neighborhood lightly while I learned more and more about road tuning and how to do it safely. This was especially frustrating because we both wanted to use the car to its fullest potential and enjoy it but without a larger budget, we had to go slow and do as much as we could on our own before resorting to a shop. Ultimately tuning brought us to a place where we replaced the entire intake piping leading to the turbo, the injector O-rings, and the exhaust manifold gaskets in an effort to get more stable boost and stable airflow rates. We swapped the injectors because as we have learned in the process of all this that we couldn’t be sure what the previous owner had installed.
Chasing down these issues took weeks on their own and so now finally after months of seriously tedious work we had the car ready to go to a serious tuner. I had learned more than I needed to get it to them safely without the motor grenading itself. The trip was 5 hours away but we knew they had every tool we need to make it run perfectly if we had missed anything.
Run perfectly is what it did. No extra work needed. We had squashed every little bug before it arrived at the real tuner saving us thousands in the end. He put it on the dyno and fine tuned my cobbled together fuel map. 375 horsepower and 371 ft-lbs of torque this time around with a smaller turbo but more usable power lower in the rev range.
On the dyno for the last time...until we decide to go faster.
This little car has taught us more in 3 years than I would’ve ever believed. Today I can swap fueling maps in 5 minutes, swap a motor in a weekend and everything in between with the right time, area and tools. It’s taught me to agonize over choices when it comes to the car I’m buying and know exactly what you’re buying, don’t take the sellers word for it. I recently added a well maintained twin turbo BMW but not before putting these lessons to good use. That story next time. For now, I’ve got a Phoenix to take to the body shop, for the last time, I hope.
vondon302
> Stephen Rivers
10/17/2019 at 08:26 | 0 |
What no dyno video?!
;)
Great write up!
Stephen Rivers
> vondon302
10/17/2019 at 08:30 | 1 |
Thank you thank you thank you. I really appreciate that.
No dyno video because it took them quite a while to get it on the dyno and then
tuned up just right and we weren’t at the shop once that happened.
Manny05x
> Stephen Rivers
10/17/2019 at 08:57 | 0 |
Nooo More cliffhangers, glad you got it to work.
Stephen Rivers
> Manny05x
10/17/2019 at 09:09 | 0 |
Thanks. It's had more since I finished writing that... But I'm still working on chapter 3. ;-)
Schaef_Camaero Z/28
> Stephen Rivers
10/17/2019 at 09:41 | 0 |
Cool story. Keep ‘em coming
Stephen Rivers
> Schaef_Camaero Z/28
10/17/2019 at 10:22 | 0 |
Thank you very much. You can count on it
acarr260
> Stephen Rivers
10/17/2019 at 10:53 | 0 |
Good stuff! Keep it coming, please.
Stephen Rivers
> acarr260
10/17/2019 at 11:08 | 0 |
Thank you. I shall
Wrong Wheel Drive (41%)
> Stephen Rivers
10/17/2019 at 12:15 | 0 |
Excellent story, always my favorite sort of oppo content. And of course hits home to me a fellow subaru owner! Will definitely keep reading.
Stephen Rivers
> Wrong Wheel Drive (41%)
10/17/2019 at 12:40 | 0 |
My pleasure. I really appreciate the positive feedback. Working on making this a regular thing.
Nicholas
> Stephen Rivers
10/18/2019 at 13:49 | 0 |
Unfortunately I learned almost the same lessons with my STI. Bought a 2014 STI on February 14th 2016. Spun a rod bearing on March 14th 2016 and made my first 550$ car payment on the car on March 15th. The car went to Boxer4Racing in NC for about 6 months. Fully forged outfront motorsports closed deck block , ported polished heads, koyo rad, killer B pickup and oil pan, rebuilt VF43 and new ACT hevy duty clutch and after 18k I had a reliable STI I could beat every day like a ragged mule..... That made 240 whp and 290 Ftlbs on a mustang Dyno that stage 2 STIs make 210 whp on.
Fast forward 1.5 years later and due to an overvealous feild mouse and some exposed acvs solenoid wiring I sent the car back to B4R and went Cobb 20g full fuel kit including flex fuel and catless DP with turbo inlet from cobb. Now after another 8k the car made 300 whp and 290 Ftlbs on 93 and 350/350 on e65 at 22 psi at 90° ambient temperature. Never been on the Dyno with cool dry air and E85 but it ramps to 25-26 psi with good fuel on a cool day so around 400/400 on the same Dyno a stock stage 2 car makes 200-210 on.
In the end always read before you buy. I love my STI and it will destroy almost anything on an autocross/ tight road coa rse but for the money I have in this car I could have a 700 whp Corvette or CTSV wagon