heinzboehmer's 2002 Topaz 6MT Coupe

[heinzboehmer]

Got a good chunk of work in yesterday.

Mechanically removed paint from all bonding surfaces:



Dry fitted the contraption I came up with to brace the thing in place while the adhesive cures:





Each individual piece is a wooden dowel with threaded inserts at each end. One end gets a threaded suction cup and the other gets one of those swiveling rubber furniture feet. The fact that both ends are threaded allows for fine adjustments once they're in place.

Dry fit was super important cause all of these needed to get installed in a short amount of time. I didn't want to be messing around with them, so I preadjusted everything and marked the locations of both ends.

The plastic coated stainless cable that's between the seats is there just in case one (or both) of the sunroof suction cups fail. Those have an extra bracket to allow articulation and are kinda heavy. I really didn't want them to come crashing down and damage my center console, so I added the cable as a precaution.

Next came final prep for the adhesive. I did a quick sand with 220 grit on both the chassis and CF brace (yes I wore a respirator when sanding the CF). On the chassis, I did an initial isopropyl wipe to get all the dust off, then an acetone wipe and then a final isopropyl wipe (new towels for each, of course). On the CF brace, I skipped the acetone wipe as I wasn't sure if it would mess with the resin, so it was just two consecutive isopropyl wipes.

With that done, it was time to mask around the bonding area and apply the adhesive. The pot life for the SikaForce 7888 is only 10 min, so this was probably the most stressful part of the whole install. No pictures of this cause I was rushing, but this was my process:

1. Apply adhesive to the entire surface and spread it out with a cut down paint brush. This is mostly to ensure that all exposed metal is covered for corrosion protection.
2. Apply more adhesive to everything but don't spread it out. Most of this will be squished out when the brace is put in place, but it's meant to help fill in any gaps between the brace and chassis.
3. Put all wooden dowels in place, starting with the top corners and working my way down the sides, then doing the rest.
4. Remove all masking tape from around the brace before the adhesive cures.
5. Squeeze out of the car through the tiny space between the buckets and b pillars while trying not to knock any of the dowels out of place.
6. Remove all masking tape in trunk.

I did not manage to get this done in 10 min. Took me 15, but the test pile of adhesive I left on the bench was still pretty liquid by the time I was done, so I don't think the extra 5 min will cause any problems.

Pulling off the masking tape in the trunk:



Masking tape pulled off in the interior and all dowels in:



Now just need to wait for an unspecified amount of time before the adhesive cures.

I say unspecified because the datasheet is incredibly vague about how long the cure time is. It mentions that "Full cure and final adhesion performance is achieved after 7 days", but then also says the specced lap shear strength is achieved after curing for "3 h at 105 °C". Later on it says "Adhesion as well as curing speed can be improved by heat up to max. 100 °C". To add to the confusion, the CSL roof repair procedure (same adhesive) says that "the endurance strength of the structural bond is achieved after 12 hours at 20 °C".

So 12 hours at room temperature or maybe 105C for 3 hours, but you're not allowed to heat it over 100C? Also potentially wait 7 days lol.

Anyway, I'm just going to leave it for 48 hours at room temp. I might run a heat gun over it for a bit today, but I didn't initially because I wasn't confident that I'd be able to keep the surface temp below 100C.

[Casa de Mesa]

The wooden dowels are cracking me up, Heinz. Your ingenuity knows no bounds! Love it! Such a simple solution to an otherwise complex problem - I mean, how would you clamp it otherwise?!?

Can't wait to hear your impressions after you let it cure for 3 hours / 12 hours / 48 hours/ 7 days and take the car for a spin.

Are you planning on having passengers in the back? Yank those seat belts if not 😁 The retractable shoulder belts are heavier than you might expect - possibly 1.5 - 2.0 lbs each, I'd suspect.

[bigjae46]

Is that the roll cage? Hahaha

[heinzboehmer]

The wooden dowels are cracking me up, Heinz. Your ingenuity knows no bounds! Love it! Such a simple solution to an otherwise complex problem - I mean, how would you clamp it otherwise?!?

Can't wait to hear your impressions after you let it cure for 3 hours / 12 hours / 48 hours/ 7 days and take the car for a spin.

Are you planning on having passengers in the back? Yank those seat belts if not 😁 The retractable shoulder belts are heavier than you might expect - possibly 1.5 - 2.0 lbs each, I'd suspect.

The dowels are definitely hilarious. First thing I thought of when I test fit them was this:



Pretty excited to drive it too, should get a chance to do it later today.

Retractable belts are gone . The bottom belts are still in only because that's what I attach the schroth quick fits too. I thought about cutting the middle belt out, but it's really not that heavy, so I just left it.

Is that the roll cage? Hahaha

Lol, they're structural dowels!

[oceansize]

Saw the band that dude is a member of back in 2000 or 2001, it was awesome. That is all.

[Casa de Mesa]

The dowels are definitely hilarious. First thing I thought of when I test fit them was this:

You were probably just as comfortable getting all those dowels in there as that dude was wearing that thing 🙂

Retractable belts are gone . The bottom belts are still in only because that's what I attach the schroth quick fits too. I thought about cutting the middle belt out, but it's really not that heavy, so I just left it.

NICE. I couldn't tell by the pic if they were there and I thought I remember seeing you had done that some time ago.

[Obioban]

I want to replicate every single thing about this install!

[Sharocks]

This is when I have to ask, is this actually worth it lol

I like having a pass through, makes the car useable since the backseats at least for me are useless now because of my Recaros.

[Obioban]

This is when I have to ask, is this actually worth it lol

I like having a pass through, makes the car useable since the backseats at least for me are useless now because of my Recaros.

If you use the fold through, probably not. I haven’t used the fold through in years.

[heinzboehmer]

Have the interior almost entirely back together now. Just need to reglue the fabric on one of my c pillars and put those in. Here's the last bit of the install:

Ended up removing a ~3mm strip from each of the front cups. Here's how everything fits now:



I did have a disappointing realization when taking all the dowels out though. Turns out the lip on the passenger side of the brace did not end up completely flush with the forward facing metal on the chassis. I did do a check for this before leaving everything to cure, but I guess trying to squeeze through the dowels made it hard for me to notice this. The gap is biggest towards the bottom, the top side was completely flush. Here's what it looks like:



I went back with some leftover epoxy and filled in the gap. Didn't do this for structural reasons, but more so to try and keep dust and other stuff out. I did do that initial coat of adhesive on all the exposed metal, so fortunately not concerned about corrosion.



I don't really think this is a super big deal, as there should be little forces in that direction and the slanted face right behind this lip is entirely in contact with the chassis.

Bizarrely, there's a protruding section of chassis in the trunk that the brace does not fully rest against and the gap from brace to that on both sides is exactly the same. I'm not sure if my chassis is different side to side or if the brace is.




Anyway, not concerned, just slightly disappointed in myself for spending so much time trying to get this perfect and missing this. It's bonded in now, so no point in dwelling on this.

Next came all the cosmetic stuff. Trunk mat and liners trimmed and reinstalled:




So far haven't heard any noises from the liners, but if I do, I'll drill a hole in them for one of those plastic push pins.

Seats back in:



Parcel shelf was a bit more annoying to refit. The brace has a lip at the top that goes over the shelf. I did consider cutting it off (since it's not really structural), but I really didn't want to cut CF, so it stayed on. Here's the lip:




The gap between chassis and brace is slightly too small to have the parcel shelf slip in, so I had to clearance that.

Bottom flattened:



Top clearanced:



Fortunately, the parcel shelf is juuust flexible enough to where I can slide it into the rear plastic trim and then push it into the gap. And with the seats up, none of my clearancing is visible:



Kinda wish I had just cut the lip off the brace, but too late for that now.

I did also get a chance to take the car out for a quick spin yesterday. Granted, I only drove it for about 15 min and not on interesting roads, but probably still worth sharing initial impressions. The biggest thing I noticed was how much less twitchy the rear felt, especially when giving it throttle coming out of a corner. It really hooks up and goes now. Feels pretty great.

Regular around town driving feels pretty similar to before. I probably need more seat time to make an accurate assessment on this, but the important part is that there are no blatantly obvious NVH downsides to this brace. Happy with that!

Next track day is in September. Very excited to see how the car behaves there.

[heinzboehmer]

Saw the band that dude is a member of back in 2000 or 2001, it was awesome. That is all.

That's awesome. Man, I really wish I had seen them when Joey Jordison was still playing with them.

You were probably just as comfortable getting all those dowels in there as that dude was wearing that thing 🙂

Oh man, I feel like the mask would be significantly more comfortable.

I want to replicate every single thing about this install!

Just don't replicate the gap on the passenger side! lol

This is when I have to ask, is this actually worth it lol

I like having a pass through, makes the car useable since the backseats at least for me are useless now because of my Recaros.

Yeah, this was a big reason why it took me so long to install this thing. I hesitated a lot cause it is nice to have the folding seats. I realized I hadn't used them in a long time and now have the E82 to do all the pickup truck work, so I just went for it. Biggest thing I'm going to miss is being able to take rear seats out and throw them through the gap into the trunk.

[heinzboehmer]

Couple lower stake projects:

First up swapping the AC panel. Had a hard time finding a used one (new is ~$900!) that wasn't beat up and I somehow ended up with three:



Buttons were scratched on two, faceplates was scratched on another two, screen was bleeding through on the last, but I managed to build a nice one out of the three:




Swapped in and so far so good, haven't seen it reboot randomly like my old one did.


Then I noticed my car suddenly stopped beeping when locking/unlocking. Troubleshooted a bit and narrowed it down to the siren. Took it apart to see if I could fix it and found this:



Annoying. New one ordered.

[Will]

What is that component, part of the siren?
Did you buy a new siren, or just the component? I think I might have similar problem with the lock/unlock beep.

Thanks for sharing your findings in this journal, I love following along seeing your work and learning along the way.

[heinzboehmer]

What is that component, part of the siren?
Did you buy a new siren, or just the component? I think I might have similar problem with the lock/unlock beep.

Thanks for sharing your findings in this journal, I love following along seeing your work and learning along the way.

I should have given more context on this. The siren has a battery inside of it so that it can go off even if the main battery is disconnected. The component in the picture above is that battery.

I ended up just buying a complete siren. I didn't find a battery that seemed trustworthy and the failed battery caused corrosion to some other components inside the siren. I did think about buying a used siren (since they're much cheaper), but all the ones I could find had build dates of 04-05 and would likely suffer a similar fate soon.

[heinzboehmer]

More low stakes stuff:

Reglued the fabric on the other c pillar that I hadn't done before:




Then disassembled 996 calipers for cerakoting. Was annoying because brake fluid gets eeeverywhere, but pretty simple in the end. Winning formula ended up being pumping air into the caliper and blocking the pistons from fully extending with some wood and cardboard and then prying them out the last couple mm:




Toothpick worked well to get the piston seals out. Went for this over a regular metal pick to not scratch the bores:



And finally, replaced the alarm siren with the new one. Car beeps again