Close enough to 2 months since last update and what an eventful 2 months it has been.
Since last track day, I came to the conclusion that the brake master cylinder was dead, and decided to go down the STI booster/MC path, because why not? Essentially this helps with brake pedal feel, particularly under heavy braking scenarios where our cars tend to have fairly spongey pedals regardless of hardware. Paired with the Shockworks brakes, this should be the be all and end all for brakes within reason. To add to my problems, the left front wheel was also incredibly wobly and felt like a front lower control arm bushing was completely destroyed - it also wouldn't hold an alignment at all.
Most relevant info can be found here as to how the swap works:
https://legacygt.com/forums/showthread. ... 81067.htmlThe main components necessary are the STI brake booster, and the Impreza MC. Both components are needed as the Impreza MC is a different mounting to our original ones. The Impreza MC is a little larger in bore, at 1 1/16 compared to the original 15/16 size. I'll update the thread at a later time with part numbers if anyone is interested in doing this themselves, but basically all info can be found on the above thread.
I won't go into huge detail on the effort necessary to do the swap, but it was around 3-4h effort for 2 of us to get the hardware installed. Much of the top section of the engine bay had to be removed to take the booster off as it's fairly tight at the firewall. Getting the booster installed was the most annoying part of this job as getting it fit on the firewall needed the right tools to thread the nuts on. The MC itself was quite easy to swap as it's 2 hardlines and 2 nuts holding it in place. Modifying the STI booster to fit also didn't prove to be that difficult if you had someone who knew what they were doing. The swap ultimately went well, and this part of the job wasn't proving to be that difficult. This is where everything decided to go downhill.
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We had planned a trip to Alpine this same week and whilst I would've normally driven the wagon, it had been sitting on jack stands for a while after getting the swap done, and not having the bushings sorted either. On the way back from Alpine in the sedan, a front ball joint decided to pop out of the control arm, sending the lower assembly straight into the front bar, front guard and door, and destroying them. After some inspection it turns out the cotter pin was non existent - and of course it was the one job I decided to give to a shop as I was too time-poor to do this myself. Combined with the fact that I was about to start a new job where a car was *vital*, this was not a great beginning. After some roadside DIY we limped the car back home, but plenty of damage was done. Now I had 2 cars that were basically non driveable to top off all my other problems.
Knowing that this will be a pain to get fixed, I started to work further on the wagon to try and get that driveable - this meant getting the brakes bled and sorting out the suspension. Thankfully JezzaH6 actually pressed in my bushings which helped *a lot* in the grand scheme of things since it was tough to find a shop to do this so quickly. Putting the lower suspension back together on the wagon proved more difficult as it turns out third-party OEM replacement ball joints did not fit, and boss-transverse links were needed. After a week of trying different methods to get the ball joints seated, it turns out they simply did not fit properly at all. A different set of cheaper ball joints did the trick and slipped in with much more ease as they should. Regardless, suspension was now mostly back together and just needed to be tightened and torqued to completeness.
The final piece of the puzzle was to bleed the brakes and re-bed everything in. From past experience and reading online, this shouldn't prove to be too difficult a job. Firstly, began by 'bench bleeding' the MC on the car, and then 'bench bleeding' the MC + hard lines to the ABS pump, then bleeding at the calipers as per normal to relieve the system of any air that may be trapped. Upon the first turn of the key, the brake pedal was incredibly light and did not appear to engage that well. After re-bleeding all calipers again, there was no change to the feel, however I did notice the front left caliper was constantly bleeding tiny air bubbles when the nipples were left open. I attributed this to air left in the ABS pump and hard lines, and continued to flush fluid through the MC. Importantly, none of the other calipers had the same issue, and considering the MC works in a split diagonal setup, I started to think there was a problem with the FL line or caliper. I eventually ran maybe 10L of fluid through just to solve this one issue, but nothing appeared to resolve it.
Since the MC was brand new, I then considered the ABS pump being faulty. I replaced it with an identical unit from a manual car to no avail either. Next, the stock STI braided line from the hardline to the caliper was replaced, again to no avail. To also rule out the caliper, a known good caliper was fitted to bleed from, also leading to no result. At this point, perhaps another 15L had been run through, and the issue only appeared to be getting worse. From running this much fluid, I also learned that fluids have a very different viscosity - and thicker fluid can actually aid braking issues where a seal may be bad. In fact, comparing Repco generic DOT4 and ATE SuperBlue fluids, the ATE fluid was heavier and separated from a dumped tub of other generic fluids!
The last component left was the new MC - was it somehow faulty? After attempting to bench bleed it multiple times, I realised it would not bench bleed! Constant air was coming out of the MC1 line port, which is the higher of the two ports on the MC. When looking at the ABS pump from top down, it is also obvious enough that the FL line was clearly the highest point of the 4 - meaning that any air would likely end up in this port only. This led me to believe that it could be a bad MC that was DOA.
I eventually sourced yet another replacement MC, and managed to install that a few days ago. This one bench bleed very quickly, and proved very promising. Only using around 2L of fluid total, I was able to bleed the entire system out. Therefore, the problem was an MC that was DOA which is incredibly unlucky. Thankfully, after around 2 1/2 months the car is finally driveable - but the wheel wobbling still remains.
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The worst part about this is that I barely had any control over how the events played out. I never would have expected a shop to not install a cotter pin, a ball joint that doesn't fit, or a DOA MC. Being absolutely sick of this and needing a car that was now critical for work, with my parents in hospital and myself nearly ending up there too along with life not going so well in other departments either, I decided it was time for another car.
After searching for around 2 months now, last week I pulled the trigger on a 2010 Lexus IS250 Prestige 6spd auto, in Molton Copper/Amber Pearl with an option beige interior (yes it is quite bright inside). Whilst watching the used car market, it was obvious enough that cars sell within a few hours of being listed if they're of decent value, so this one was bought within just 2 business hours of listing with no photos or details! It only has 66kkms on it, and 1 lady owner who treated it with care. It's in excellent condition and is by far the cleanest IS I've ever seen. It had most of the options I was after except the Mark Levinson audio system, but I was willing to overlook it for such a clean example. Hopefully, this car represents life getting a bit better again. My limited time with it has proved to be amazing and I see myself in another Lexus in the future.
Yesterday was the first day that both Libs were *functional*, so took the opportunity to take a few photos with the fleet before I decide what to do next.
by JezzaH6 » Wed Mar 10, 2021 7:11 pm 
Have you noticed any differences so far with the new oil pump specifically? Thought you would've had head studs already too! Looks like a nice build you've got yourself there. How is that VF52 treating you thus far? 
