'22 Subaru BRZ

[DocWalt]

We made the boring drive up to Pocono early yesterday for NEPA, the event was fantastic and we had a blast just driving and thrashing the car all day. Super fast and fun course, a real challenge.

I pulled off the fastest street tire run by a good amount and was second in PAX behind Jon in his STX FR-S, not bad at all!



Amy finished up 5th in STR and solidly in the top half of PAX even with her never getting very comfortable with shifting. The pedal placement in the BRZ is definitely not as good as in the RX-8 for shifting under duress. Proud of her for sending it even not being comfortable!








Had a new addition before the event too! Picked up a Perrin intake used from a friend:

[j2k4]

That Pocono track looked like a total blast, Ken.

[DocWalt]

That Pocono track looked like a total blast, Ken.

One of my favorites. I can't wait to get on an open track, been way too busy!

[DocWalt]

Had a fun day with Philly & WDCR at Ripken stadium, pulled off another 2nd place in PAX and a win in STR. My car is working really really well, I ordered an OS Giken diff tuned by Shaftworks USA and I'm not even sure I need it, haha. I'll be installing that soon, but for now, a video of my fastest run. Amusingly, like every other Ripken event, I don't seem to find any time after my first run... Annoying, but glad I'm on pace right away at least haha.






I installed my Shaftworks USA tuned OS Giken Super Lock LSD this past weekend! Install went smoothly and no leaks. Here are some install pics, my feedback so far (very very limited feedback) is below.




Subaru *can* use the correct amount of RTV, wow!








The break in instructions for the diff, which explains the lack of meaningful feedback




Ring gear all torqued on with orange threadlocker in lieu of the stock locking tabs. Marked for future inspection.




Diff backlash checked out perfectly in spec, at the tighter end but NBD. The diff has less whine on decel now, haha.








Waiting for the cover sealant to cure, bored...




Installed a polyurethane shifter bushing, mostly because it was cheap. I've noticed no meaningful difference.




So for some initial feedback... With the caveat that I now have ~15 miles on the diff (of the 1500 street miles for full break in) and I'm using Motorcraft fluid, not the fancy OS Giken fluid.

The diff chatters bad on power in tight corners in my neighborhood but does not when coasting. I assume this is mostly just the oil, my ND Miata was silent and smooth as silk.

Feels awesome when attacking, drifts are super progressive and less snappy. When it's not drifting it just carves the line you picked, like it did on my ND. So you're on a line and you get on the gas and the nose almost wants to tuck itself in to counteract the natural push.

Seems to put power down better too, duh?

[stealthee]

Nice.

[DocWalt]

I was a bit tired of the chattery/binding from the cheap break in fluid... So I swapped to the OSG fluid, haha.

With the Motorcraft fluid, the diff felt like it was sort of sticking. Driving around casually I'd go to turn in and the car sort of fought me until I took my foot off the gas and went to neutral throttle and the diff opened up.

The diff took a bit to work the other fluid out but now it's essentially silent and smooth. Feels really good. Just yeet it around corners and floor it and you get a super smooth progressive slide, like the diff is actively working to push you forward and arrest the slide. I can't wait to see how it does at autocross now!

[DocWalt]

Did my first autocross yesterday on the new diff. Simmons codrove as well, so lots of runs and good competition! The diff definitely needs more break in usage and some dry runs, but so far the car seems more stable on entry and puts power down better on exit. Less snappy and you can be way more aggressive on power. I'm really curious how it behaves in the dry!

Here's my fastest run, good for 2nd in PAX. I was slower than Simmons in the slalom and a good bit slower into the far turnaround as well, I just braked too early.




Here's Simmons first (and only ) clean run in my car:



Here's his fastest run, with two wobbles of cones that just slid out of their boxes. He was taking it safe in the faster/sketchier places due to the conditions which I appreciate haha:

[j2k4]

Your 'new diff' experience made me think of my '71 Mustang with the locker - noisy as hell cornering, in town - the clutching was always sticky, and the only relief was using Ford's own product for that specific diff, though it wasn't entirely effective.

I remember being supremely irritated that a certain girl who liked my car decided to tell all her friends she thought there was something wrong with my rear-end.

[DocWalt]

Your 'new diff' experience made me think of my '71 Mustang with the locker - noisy as hell cornering, in town - the clutching was always sticky, and the only relief was using Ford's own product for that specific diff, though it wasn't entirely effective.

I remember being supremely irritated that a certain girl who liked my car decided to tell all her friends she thought there was something wrong with my rear-end.

Yep, the good old Ford Limited Slip additive, haha!

[DocWalt]

This weekend was Philadelphia SCCA region's Al Holbert Memorial autocross weekend. I've been the winner of the two day event the last two years, but this year with my class having a harder PAX handicap and having the "wrong car" for my class I knew it would be tough. I was able to just pull off the win last year even with the "wrong car" but competition has been really stiff this year! Lots of really fast drivers in the Philly region and we had drivers visiting from all around!

Day one was great, Amy and I were getting used to the new OS Giken diff, more on that later. Amy was super happy with the car and I felt like it was easier too. We did pretty darn well, I won STR and was sitting fourth for the Holbert trophy. Amy was really competitive in STR as well!

Amy's fastest run:



My fastest run:



I went a little faster on my 5th run when I really learned the diff, but I tagged a stupid cone in the process.



Amy was very happy on day 1!




Day two was even more fun, but other folks got faster! I ended up finishing fourth for the Holbert, less than a half second back over two days. Not at all unhappy considering the limitations of my car in STR. Amy had a weird issue on one run, the car popped out of first gear for no apparent reason about 25 feet off the line.

Amy's fastest on day 2:



My fastest run on day 2:




For feedback on the differential, Jon at Shaftworks USA *killed it* on the diff! It's a pretty decent difference in driving style, but it's really rewarding and fun to get it right... and more importantly I think it's made the car faster. The car is more stable on entry and really really forgiving of chucking the car around. When you're mid corner in a sweeper and you feel like the front end isn't going to hold on anymore, you can start to roll on the gas and it just tucks the nose wherever you have the steering wheel pointed. SOOOO nice to be able to get on the gas earlier and power out of the corner sooner. On top of the behavior change, the new differential puts down power over bumps so much better than the stock Torsen limited slip, it just accelerates forwards all the time instead of chattering and hopping.