heinzboehmer's 2002 Topaz 6MT Coupe

[YoitsTmac]

Dang man, glad you're okay!

[Obioban]

Ha.

Last Saturday I was tracking while sick and accidentally had a 100+ mph off roading session. Happily recognized it was happening and went off straight, got control, pulled her back on... no damage at all.

Certainly the fastest I've ever driven on grass. Sketchy.

Downgraded myself to intermediate for the next day, so I could take it slow.

[heinzboehmer]

Dang man, glad you're okay!

Thanks! Still can't believe I didn't hit anyone or anything. Best worst case for sure.

Ha.

Last Saturday I was tracking while sick and accidentally had a 100+ mph off roading session. Happily recognized it was happening and went off straight, got control, pulled her back on... no damage at all.

Certainly the fastest I've ever driven on grass. Sketchy.

Downgraded myself to intermediate for the next day, so I could take it slow.

Glad there was no damage!

My excursion would have been similar to yours had that curb not been there. Really messed with the grip in the rear when getting to the bottom of the hill.

Still haven't pulled video off of my car, but this is pretty much exactly what I did: https://www.youtube.com/watch?v=1Fg_vP5IYRA

[Obioban]

Glad there was no damage!

My excursion would have been similar to yours had that curb not been there. Really messed with the grip in the rear when getting to the bottom of the hill.

Still haven't pulled video off of my car, but this is pretty much exactly what I did: https://www.youtube.com/watch?v=1Fg_vP5IYRA

That looks exciting

[oceansize]

Track day done. Some ups, one big down.

Let's start with the good stuff.

HK amp was really dying, so I picked a used one up, did a quick refresh on it (cleaned up and refreshed the thermal paste) and swapped it in:



And wow! I can't believe I had been putting up with the old amp for the last couple years. This thing sounds so much better. I kept having to turn the music down on the drive to the track cause I would hear details that I hadn't heard before and would think they were coming from the car. Pretty happy with this.

Then came a bit of CAD work. Scanned my hacked up filter housing prototype and made the changes necessary for installing:



I have to say that the 3D printer + scanner combo is incredibly powerful. Iterating on this piece would have taken way, way longer had I not had access to these tools.

Test fit piece printing now. Once that is validated, I can move on to printing the entire thing out of PET-CF.

Also, good news is that I didn't see the windshield mount temp go above 70 C, even after letting the car heatsoak in the sun for an hour or so. I'll pull the data later and grab the actual numbers.

But now, the bad news. During one of the afternoon sessions, I came in a bit too hot into Phil Hill and completely missed the turn. Landed with the left tires in the dirt and the right on the pavement, which means I hit the curb at the bottom of the hill pretty hard against the undercarriage. I then drove back onto the pavement for a second and lost it again, spinning out into the dirt on the left side of the track.

Fortunately, the aluminum shear plate took ALL of the damage. I still can't believe I got as lucky as I did. Absolutely nothing else was damaged (including the brake and fuel lines right behind where I hit the car on the curb) and the car stayed right side up.

Having used up all of my luck, I decided to call it and spent the rest of the day cleaning the car up, which wasn't exactly fun. This is what the interior looked like immediately after coming into the paddock:

Vacuumed out what I could, then used compressed air from the tire shop to blow out the rest. Still needs a serious detail (which unfortunately involves removing a ton of the interior trim pieces to get behind them), but all in all, not a terrible result:

Replacement parts ordered. Will spend some hours this week disassembling and cleaning up the car, then can analyze the thermocouple data.

All in all, not the best track day experience I've had, but very glad it wasn't worse. Car drove straight for the entire four hour drive home, all fluids stayed in their places, E86 braces survived and most importantly, no one was hurt.

Hence the old saying "I would rather be lucky than good" 🤣

[Slideways]

[bigjae46]

But now, the bad news. During one of the afternoon sessions, I came in a bit too hot into Phil Hill and completely missed the turn. Landed with the left tires in the dirt and the right on the pavement, which means I hit the curb at the bottom of the hill pretty hard against the undercarriage. I then drove back onto the pavement for a second and lost it again, spinning out into the dirt on the left side of the track.

Fortunately, the aluminum shear plate took ALL of the damage. I still can't believe I got as lucky as I did. Absolutely nothing else was damaged (including the brake and fuel lines right behind where I hit the car on the curb) and the car stayed right side up.

The worst part is not knowing how bad the damage is until you get into the paddock.

Let me know if you want a carbon plate!

[maupineda]

T


But now, the bad news. During one of the afternoon sessions, I came in a bit too hot into Phil Hill and completely missed the turn. Landed with the left tires in the dirt and the right on the pavement, which means I hit the curb at the bottom of the hill pretty hard against the undercarriage. I then drove back onto the pavement for a second and lost it again, spinning out into the dirt on the left side of the track.

Fortunately, the aluminum shear plate took ALL of the damage. I still can't believe I got as lucky as I did. Absolutely nothing else was damaged (including the brake and fuel lines right behind where I hit the car on the curb) and the car stayed right side up..

Want to run the carbon plate I am not using?

[Arclitgold]

Glad you’re ok!

Im nerdily watching the progress on the filter housing! Nice work

[0-60motorsports]

Want to run the carbon plate I am not using?

I would love to get one, one day, but the steel one is much better and stronger for impacts and wont shatter.

[heinzboehmer]

Glad you’re ok!

Im nerdily watching the progress on the filter housing! Nice work

Thanks! All the damn cleaning put a dent in the progress with that, but have a new revision almost ready to print. Battling some install issues, but I'm sure I can make it work. Should be able to get to that soon.

The worst part is not knowing how bad the damage is until you get into the paddock.

Let me know if you want a carbon plate!

Want to run the carbon plate I am not using?

I would love to get one, one day, but the steel one is much better and stronger for impacts and wont shatter.

Appreciate the offers on the carbon plates, but I think I'm gonna stick with the metal one, for the same reasons 0-60motorsports pointed out. I can't promise that I won't do this again and shattering a carbon one sounds pretty scary.

And now for the moment of shame:

https://www.youtube.com/watch?v=DVXukfuyi3A

As is obvious, this was 100% a driver skill issue. The car is clearly unsettled and struggling for grip from a few corners back (note how twitchy my hands are in the long sweeper). I should have slowed down more in the braking zone for Phil Hill, made sure the car was settled and then attempted the corner. Going in too hot + weight in the wrong places + a bit of understeer at the crest was more than enough to send me flying.

Post-impact, I think my steering inputs were good, but I should have reacted a bit quicker with the throttle. Had I done that, I might have neen able to carry the drift and avoid the mouthful of dust. Wouldn't have helped with the damage to the shear plate, but at least everything wouldn't have gotten so damn dusty.

Also, you can see me give up on trying to save it and just go WOT after the second countersteer. It became clear that I was gonna go off sideways one way or another and that was my attempt at scrubbing speed NOW. There was some very dry looking sand right next to the track and some wetter looking stuff a bit further out. I was afraid of hitting the mud sideways and rolling, so I opted to spin out instead. Not sure if that was the correct choice, but hey, that's the decision my brain made in the moment.

[heinzboehmer]

Many, many hours later, the interior is clean again.

I started by just vacuuming things out, but I just kept finding dust/sand everywhere. Started taking things apart and quickly arrived at this:




Ended up basically taking the entire interior apart. Was crazy to see just how far into things the dust made it.

For instance, found sand dunes in the trim for the rearview mirror:



I guess that's not too crazy, since it's not exactly a sealed part. But look at this:



It got inside the rearview mirror. How!?

Unfortunately, I broke the ribbon cable for the homelink module when taking it apart, so had to break out an emergency repair:



I smeared a bunch of glue on top of the solder butt joint to try and make it reliable, but I can't imagine this fix will last long. Oh well. At least the daughterboard with the ribbon and buttons should be an easy piece to scavenge out of a junkyard mirror. Added to the list.

I also took anything with buttons apart and cleaned out everything on the inside. This is what all of the buttons on the car looked like and why everything felt crunchy when pressed:



Funnily enough, now some of the buttons are so clean that they squeak when pressed. Bought some of the Krytox that comes in a bottle with a syringe cap, so will go around the car with it to make everything nice again.

Most of the interior is back together, but I still need to reglue some of the fabric on the A pillar fastener covers that came off and fix a broken tab on one of my c pillars. Will post some pics of that later.

[heinzboehmer]

Enough of driving myself crazy over some dust and onto more interesting topics:

Finally sat down to analyze the thermocouple data. Quick notes on the test setup:

• Logged as many scenarios as I could, so data would include multiple driving styles (highway, around town, on track).
• Track day was at Buttonwillow 13CW.
• Ambient temps were between 20-28 C.
• No clouds, sun was out all day.
• Car was purposefully not parked in the shade to maximize heatsoak.

Alright, let's jump straight to the analysis. Unfortunately, there is way too much data for datazap to handle, so you guys only get non-interactive images this time. Here's everything I captured throughout the day concatenated into one big chart (vertical discontinuities are from when the ignition was off, x axis is time elapsed):



Some key takeways after looking through the data:

• Any airflow in the engine bay quickly drops temps for all thermocouple locations (more on that in a bit).
• Temps behind the firewall consistently trail engine bay temps by ~20 C, which means the thermal insulation properties of the 3D printed parts work!
• At steady state, the engine bay thermocouples settle at ~60 C and the ones behind the firewall settle at ~40 C.
• Convection seems to play a bigger role in the temps of these parts vs radiation.
• Max values for each location follow:
  • Firewall Plug: 84.1 C
  • Passenger Brace Underside: 86.8 C
  • Windshield Mount Front: 65.5 C
  • Windshield Mount Rear: 63.9 C

During one of the track sessions, I decided to completely skip any cooldown and park the car as fast as possible in the paddock to maximize heatsoak in the engine bay. This was, of course, a dumb idea. I parked the car and my front brakes immediately began to smoke (I'm guessing the dust boots are once again toast, yay), so I had to jump back in the car and drive it around the paddock for a bit to cool them down.

Regardless of the impromptu cooldown, I still managed to get the highest engine bay temps during this part of the experiment. Here's a zoomed in and annotated view on just that part of the data:



The "Engine On" and "Drive Through Paddock" sections showcase my previous airflow comment perfectly. As soon as you start moving any air in the engine bay (from fans or from driving around), the temps drop rapidly. Pretty cool to see.

Anyway, key takeaway from this testing is that the windshield mount is not getting nearly hot enough for 7075 temp degradation to be a concern. Very happy to see that .

[Arclitgold]

Nice work!! The car lives to fight another day

[heinzboehmer]

parked the car and my front brakes immediately began to smoke (I'm guessing the dust boots are once again toast, yay), so I had to jump back in the car and drive it around the paddock for a bit to cool them down.

Well, turns out I was wrong.

Swapped back to street pads today and I couldn't find a single crack on any of the dust boots. They're all still in perfect shape:



Honestly kinda blown away that the dust boots survived that.

Also, I have no idea what did catch on fire, but I can tell you that smoke was pouring out of both front wheels before I hopped back in to do the cooldown lap of the paddock. Maybe it was from tire rubber stuck to the inside of the wheels?

Anyway, I'm super happy that I don't have to swap the dust boots out for the millionth time.

Nice work!! The car lives to fight another day

This thing is tougher than I thought!