'23 BRZ Manual Track Build

[Code Monkey]

For spacers, I recommend Motorsport Tech, they can make any width you wish.

[X25]

I wanted to try the car in stock suspension for one last time before I install the coilovers:

• I improved the PB with this car to 2:03.93. I just came back from our overseas trip 2 days ago, and I'm a bit jetlagged, so I only did one long session : )
• Shifting is still an issue, and I kept having mishaps. I actually mis-shifted to lower gear once, but thankfully it only hit 7850 RPM before I clutched back in.
• I am not sure if the shifting is something that happens (misalignment) with the car, or if it's just me shifting on the stock seat. Switching to race seat and harness will hopefully answer this question : )
• Tires seem to have started wearing down a bit faster than I thought. I'm guessing -2.5 camber is not cutting it.

Perrin's tow hook is pretty light. I think it's a bit less than 1 lb, but my scale is not sensitive to that low of weight : P



Perrin states no modification needed, but you certainly do.



The stem of the tow hook quickly got damaged as I tightened it. I sprayed a bit of gloss black paint on it.


Well, glad that I got black. It looks a bit too big, so a blending-in color is good : )



I also brewed my own coffee in the morning, thanks to the 120V ports of the truck; this was fun! I'll definitely do it from now on, but with better coffee than that bitter Jacobs gold.



The tires seem to have had a tough life after only two track days, and I only did 1 1-hour session today. I suppose the low front camber (-2.5) that I could get from the stock suspension is not helping.



Tires spun a bit on the wheels. The white markings were aligned with the valve-stems during the mounting. We'll see what happens with the 17x9 APEX wheels, but I was surprised to see this with only 225 wide tires.


How the car looks like right now...

[autosenses]

Originally Posted by X25

I wanted to try the car in stock suspension for one last time before I install the coilovers:

• I improved the PB with this car to 2:03.93. I just came back from our overseas trip 2 days ago, and I'm a bit jetlagged, so I only did one long session : )
• Shifting is still an issue, and I kept having mishaps. I actually mis-shifted to lower gear once, but thankfully it only hit 7850 RPM before I clutched back in.
• I am not sure if the shifting is something that happens (misalignment) with the car, or if it's just me shifting on the stock seat. Switching to race seat and harness will hopefully answer this question : )
• Tires seem to have started wearing down a bit faster than I thought. I'm guessing -2.5 camber is not cutting it.

Perrin's tow hook is pretty light. I think it's a bit less than 1 lb, but my scale is not sensitive to that low of weight : P



Perrin states no modification needed, but you certainly do.



The stem of the tow hook quickly got damaged as I tightened it. I sprayed a bit of gloss black paint on it.


Well, glad that I got black. It looks a bit too big, so a blending-in color is good : )



I also brewed my own coffee in the morning, thanks to the 120V ports of the truck; this was fun! I'll definitely do it from now on, but with better coffee than that bitter Jacobs gold.



The tires seem to have had a tough life after only two track days, and I only did 1 1-hour session today. I suppose the low front camber (-2.5) that I could get from the stock suspension is not helping.



Tires spun a bit on the wheels. The white markings were aligned with the valve-stems during the mounting. We'll see what happens with the 17x9 APEX wheels, but I was surprised to see this with only 225 wide tires.


How the car looks like right now...

Love the build. Incredible the tires spun on the barrel. 5th Gen Z28's did this...Apex wheels should have those grooves or notches in them to prevent the tire from spinning.

[X25]

Thanks, glad you like it : )


Yeah, I used to own a gen 5 Camaro ZL1, and remember it from that time, too.

My C7 Z06 also spins the tires on the wheels despite the wheels having knurled beads already. My tire shop mounts the tires with no soap to reduce the slip, and it helps a lot. It also helps if you can wait a bit for tires to warm up before you apply hard braking (which seems to be what spins the tires on the wheels).

My next lap right after this video is cut was faster than all, pacing 2:03.6, but had to slow down 2 turns to finish due to a yellow flag and a spun BMW. So in a way, I'm sure I can extract a wee bit more, but I'm running out of time with the season getting over real soon here in the Pacific Northwest. Next time, I'm planning have the coilovers on.

[autosenses]

brewing your own coffee at the track is a big brain move. I added that to my list for my next track day.

[gcmak]

I've slowly gained camber over time and it's sad with the strut-based front suspension that you really do need quite a bit of camber for serious track or autox work (if you want your tires to wear more evenly among over things). While I'm not using a pyrometer, even at -3.2 degrees now, things aren't where they should ideally be. I'm starting to think the people running -4 degrees have their reasons. The rear's a better story though. For me at least, -2.5 has been acceptable. Keep up the good work!

[X25]

I decided to use the car for commute today, and took another look at the front tires. Looks like the driver side has worn down to zero by where I am pointing at. Considering I've used these tires for only 1.5 track days, it's quite a short life.

Anyway, stock suspension is not ideal, neither is the -2.5 max camber I could get off of these, and I'm guessing it went above ideal pressure as well during the session. In any case, we will revisit all this once I install the coilovers.

[X25]

So, it turns out Perrin tow hook is not really a tow hook, or at least it's nowhere near as tough as how it should be, or how my other tow hooks are for my Corvette.

I winched my car for 1 event with the Perrin tow hook, and despite the relatively low angle of 3-5 degrees from the winch on the Futura kneeling trailer, the tow hook is bent : (



You can see how the bottom stem is bent.


Decided to reinstall the OEM hook, but this time I painted it black first, so it'd not stick out from far.


The hole I had to carve for the Perrin tow hook-alike accessory is a good match for the OEM tow hook as well, so the install was a few seconds of twisting : )



I'm still waiting on the Titan harness bar for the install of race seats, race harness, and coilovers. Here's hoping they send it soon!

[EndlessAzure]

Not sure how I feel about the Titan Motorsports Roll Bar.

The cell seems a little open, but that is subjective. The description seems to focus a lot on comfort and non-intrusiveness, which is a little different than what I'm used to for roll cages.

But what stood out most and gave pause was the bolting points. It looks to only bolt in 4 places, two of which being OEM front seat belt point, two being the child seat belt point. I question if the front seat belt bolt point is suitable. Child seat anchors are definitely not suitable, and even if it bolts to the body cross bar underneath, I'm not sure how strong that part of the car is when loaded in a rollover. Most other roll cages drill extra bolt holes into the chassis with reinforcing plates. For rear mounting, they bolt to the floor beam behind/under the rear seats

This roll bar situation gives me the same tow hook vibes. Very few aftermarket tow hooks are rated for actually recovering cars; this bar is supposed to save you.

[X25]

Originally Posted by EndlessAzure

Not sure how I feel about the Titan Motorsports Roll Bar.

The cell seems a little open, but that is subjective. The description seems to focus a lot on comfort and non-intrusiveness, which is a little different than what I'm used to for roll cages.

But what stood out most and gave pause was the bolting points. It looks to only bolt in 4 places, two of which being OEM front seat belt point, two being the child seat belt point. I question if the front seat belt bolt point is suitable. Child seat anchors are definitely not suitable, and even if it bolts to the body cross bar underneath, I'm not sure how strong that part of the car is when loaded in a rollover. Most other roll cages drill extra bolt holes into the chassis with reinforcing plates. For rear mounting, they bolt to the floor beam behind/under the rear seats

This roll bar situation gives me the same tow hook vibes. Very few aftermarket tow hooks are rated for actually recovering cars; this bar is supposed to save you.

Yeah, this is not really a full on safety cage, and I am not planning to solely rely on it for safety. The seat belt (front) locations should be good, since they're designed to be one of the strongest locations. IIRC, there's even a government requirement of them being rated at least 3000 lbs in load strength (meaning almost 10K lbs for sudden loads before failure). That said, the child seat anchors are only rated for 75 lbs pull. Of course, these are minimum requirements IIRC, and one thing that should help is that the force might be more push than pull on those rear anchors during a roll-over, and they'd likely be more robust for that, being right above the cross bar, etc. Alas, that's speculation.

I will only be using Schroth Profi II in this car, which, as many of you know, is designed to work on street cars with a double-stitched inner shoulder belt, popping the stitches in the event of an accident. As such, it is DOT approved for use in regular cars. In a way, the harness should 'unpin' me in the event of an accident, increasing my odds are survival in a roof collapse.

I've actually tested out this seat belt in 2016; it works as intended : P

I will post more about the Titan bar when I get to install it.

Regarding tow hook, that was disappointing. I did not even tow the car per se, and just used it along with the winch, slowly pulling in on a surface at less than 5 degrees angle, and for such a lightweight car. Anyway, I'm glad OEM hook is not too heavy.

[EndlessAzure]

It looks like you are convinced in its design and this application of safery equipment (I am not). The forces required to hold and exerted on a human pale in comparison to the loads that the car's structure will experience in a crash. I have no doubt the bar can support your weight, but the worst case is if the bar breaks away from the car. Then nothing is holding you.

Nonetheless, I think you should reconsider this idea of a cage as a simply a harness bar. With the philosophy you mentioned, you would be safer with a Schroth Rallye 3 and no harness bar. The Rallye 3 single overshoulder link can be bolted to the rear passenger belt upper or lower restraint point.

For not much more money (and a little bit of interior modding), you can get a serious bolt-in/semi weld cage

[X25]

Hmm I never said I am convinced it is a good roll cage, but in short, it's at least as good as a harness bar, and my other choice was BK harness bar. In time, if I decide to turn this into a full-on race car, I have an excellent local fabricator here who could build it out for me : )

Rallye 3 is similar to Profi II ASM that I have, and they provide about similar levels of safety. With Profi II ASM, though, I can easily add sub belts as well, and that works much better with the Sparco EVO L QRT race seats I'll also be installing. I tried Rallye 3 before, I never liked its twisted angle that happens with the way it's mounted. I'm also not sure if it would even work right with a race seat anyway.

In short:
Profi II ASM
Titan roll/harness bar
Sparco EVO L QRT

We'll see how Titan bar even mounts to this car; looking forward to it : )

[NoHaveMSG]

Crazy the Perrin tow hook bent like that. My Raceseng tow hook is fine and I’ve had to use it. I’d shoot Perrin an email.

[X25]

Originally Posted by NoHaveMSG

Crazy the Perrin tow hook bent like that. My Raceseng tow hook is fine and I’ve had to use it. I’d shoot Perrin an email.

Yeah, I sent them an email yesterday. I'm still pending their reply...