STX setup sharing thread (2021)

[cjd]

I have the Thermal. It's a few lbs lighter than stock (weighed in at 37lbs), and while I can't compare fairly to stock (it went on with the Ace 350) it is quiet enough to be comfortable on road trips (also running a 3" FP with hfc and resonator), has no noticeable drone (well designed Helmholtz doing its job), and a surprisingly small build. Tire noise or diff noise (I have all the diff mount bits) are louder usually.

[bslate3]

I have the gruppe S header, Tomei overpipe, Motive front pipe and CSG touring 86 cat back. It’s pretty darn quiet.

My friend and I have been looking at building a light weight replacement muffler option that will fit onto the CSG cat back. We found a Hushmuffler that fits up pretty well with just 2 90’ bends and sounds pretty damn good without being crazy loud and is half the weight as the CSG muffler.

Is it worth the hassle so save about 8lbs? Who knows lol

[Breezio]

I highly enjoy my HKS Hi-Power Spec-L
Significantly lighter, compact mufflers. It's not quiet, but it's not loud either.
I'll have to double check on clearance around the sway bar and endlinks. But it should be pretty good.

[steverife]

The HKS looks like it wouldn't rub driving interstate exits in Missouri. But might be worse for getting to end links with the car on the ground for a quick nut check under load.

[Lincoln Logs]

Originally Posted by cjd

I have the Thermal. It's a few lbs lighter than stock (weighed in at 37lbs), and while I can't compare fairly to stock (it went on with the Ace 350) it is quiet enough to be comfortable on road trips (also running a 3" FP with hfc and resonator), has no noticeable drone (well designed Helmholtz doing its job), and a surprisingly small build. Tire noise or diff noise (I have all the diff mount bits) are louder usually.

Thermal R&D exhaust is the best exhaust, hands down. Zero drone and a refined sound.

[RT-BRZ]

Since my season is basically done for Solo, what are everyone's thoughts on tire size? I ran RT660's in 255/40/17 and I thought they were fine but as the season progressed I always felt like I was a little off from others in BRZ/FRS/86 cars. At first I just chalked it up to my skill level but I ran a Track Event at Mid-Ohio in September and the car was definitely slower than last year when I ran 245/40/17's and no tune or header or any of the significant STX prep I did.

So, I feel like the verdict is that the 255's are actually a detriment but I am wondering what everyone else has experienced or thinks.

[strat61caster]

Haven't tried 255s, never felt like the early cars needed taller gearing that comes with that tire, never did any maths or anything just a gut feeling that's the bigger impact then width or mass.

[Breezio]

In general people don't run them on the 13-16 cars. I run 255's on my 2017 and it helps a little bit. Otherwise 2nd gear is just way too short. Heck, even with the 255's I top out at 55mph.

Off handedly I would chalk up being a little bit behind because of your tire choice, not your tire size. If you aren't running Yoks on a twin in STX, you aren't trying to win. Second best would be the Nankang CR1.

[Kelse92]

I ran the Nankangs for a bit when Yoks weren’t available, there honestly isn’t really any reason to run the Nanakngs over them other than that. They’re both about the same price once you pay for shipping from PTS. I was curious about what everyone was running at nats and looked at all the cars and pretty much 95% of the cars were on 245’s

[renfield90]

Originally Posted by RT-BRZ

Since my season is basically done for Solo, what are everyone's thoughts on tire size? I ran RT660's in 255/40/17 and I thought they were fine but as the season progressed I always felt like I was a little off from others in BRZ/FRS/86 cars. At first I just chalked it up to my skill level but I ran a Track Event at Mid-Ohio in September and the car was definitely slower than last year when I ran 245/40/17's and no tune or header or any of the significant STX prep I did.

So, I feel like the verdict is that the 255's are actually a detriment but I am wondering what everyone else has experienced or thinks.

I've tried. I don't feel like it worked that well, here's my mental model for how they fare.

255s are a bonus on speed maintenance courses that also have a sustained high speed section at around 63mph. You're slightly faster than everyone on 245s there. So, like 10% of courses.

On pure speed maintenance courses (zero digs) with top speed <= 62mph (245s not bothered by the rev limiter) or with top speed > 64mph (everyone deep into third), there is no advantage either way. This is maybe 30-40% of courses.

If there is even one or two big digs (so all other courses), you get destroyed by everyone on 245s. Generally speaking our cars are thrust-limited coming out of digs, not traction-limited, and you are reducing thrust.

Bottom line is wider rubber should help in theory, but the gearing changes add a course dependency factor that is much larger than any extra grip you might get.

[Autoxer62]

Is anyone running the Borla Type S exhaust? I was thinking that one ticks all the boxes - a little lighter (10 pounds as I recall), not too loud, and from the looks of it should have really good clearance since the muffler's in the center of the car. Any first hand experience?

[RT-BRZ]

Originally Posted by renfield90

I've tried. I don't feel like it worked that well, here's my mental model for how they fare.

255s are a bonus on speed maintenance courses that also have a sustained high speed section at around 63mph. You're slightly faster than everyone on 245s there. So, like 10% of courses.

On pure speed maintenance courses (zero digs) with top speed <= 62mph (245s not bothered by the rev limiter) or with top speed > 64mph (everyone deep into third), there is no advantage either way. This is maybe 30-40% of courses.

If there is even one or two big digs (so all other courses), you get destroyed by everyone on 245s. Generally speaking our cars are thrust-limited coming out of digs, not traction-limited, and you are reducing thrust.

Bottom line is wider rubber should help in theory, but the gearing changes add a course dependency factor that is much larger than any extra grip you might get.

Here's a video of a course that's short and tight:

In reviewing the run I felt like the car just didn't stay in the RPM range I would have preferred and that tires causing a taller effective gear ratio is the real problem. I was only about one second off the fastest cars of the day (Supra and '16 M2) but it still didn't feel like I was getting the most out of my setup.

(side note; I know I have a lot of opportunity to improve my driving. I'm just demonstrating what I'm seeing.)

[racingfool]

Originally Posted by Breezio

even with the 255's I top out at 55mph.

At 7000 rpm?

[Breezio]

Originally Posted by racingfool

At 7000 rpm?

Just reviewed my data, 56mph, barely touching 57mph at 7500 rpm.