Seattle Snake - Roadster mk5 - Build Thread
This build was previously teased on a planning thread, but it's time to start the Build Thread! Our kit should be finishing mid-January and arriving in February or March.
Build Plan: (preliminary - [edit] see a few posts down for the updated version)
- Coyote gen 4x or gen 3 engine
- TKX transmission
- IRS rear end
- 11" and 13" IRS brakes
- Hydraulic Clutch (Forte)
- Power Steering (Forte)
- 2x Triple Gauges (Tach and Speedo) from Speedhut (center of dash will be small backup camera/carplay screen)
- Carbon Fiber Dash w/glovebox (FFR)
- Heater/Defroster (FFR's Vintage Air kit)
- Windshield Wipers (SPW)
- Dual Rollbars Chrome (FFR)
- Sidepipes and headers (FFR)
- Side pipes heat shields (CobraStuff)
- Remote Break Booster (FFR)
- Cobra Seats Classic CS (cobra-style seats w/ headrests for safety)
- 17" wheels (FFR)
- Hard or Soft-top for 3-season driving (FFR)
... and a bunch of mods and tweaks we'll cover later when relevant.
Planning to do my own body work and paint, for a temp paint job at least, but if it comes out nice enough I might keep it. I have a decent amount of experience with resin models and airbrushing at the small scale, so I'm excited to scale up to spray guns and fiberglass (yes, I know about scary paint chemicals and fiberglass dust).
This is a joint build project with myself and my son (12). We will be attending Build School in April.
Update 1 - December 29, 2025
The Chassis Sled
To make the chassis easier to work on, we've fabricated a sled to store it on, until we get to the 'roller' stage.
We are repurposing some 'pipe trays' (for storing pipes for a pipe organ), by bolting two of them together and then adding some high-weight capacity wheels and a bit of carpet on the top. Dimensions of the sled are 8' x 4'.
We just used the scraps of carpet we had lying around, and they don't quite cover the sled, but we will recut the carpet if needed to match the chassis once we get it (and we have some extra carpet on a roll too).
If you make your own sled, I recommend building it out of a single 8x4' board with horizontal bracing, but since we want to re-use these as pipe trays again in the future, we stuck with what we had.
Chassis Sled Top View
https://drive.google.com/file/d/1auA...usp=drive_link
Chassis Sled Bottom View
https://drive.google.com/file/d/1XMW...usp=drive_link
The Body Buck
We also started on the body buck for storing the body while we work on the chassis:
Body Buck Front Panel
https://drive.google.com/file/d/1Rin...usp=drive_link
1 Attachment(s)
Week 5 Update - Heater modifications and Liner Experiments
Heat Liner Experiments
I want a blackish engine-bay, so I didn't want to use a foil heat liner. I tried using "FireWall" coating, but I didn't like how it painted on, very hard to get a smooth coat.
FireWall Coating Attempt
I ended up sanding all the paint off and cutting some Damplifier Pro (2mm) as my engine-side heat/sound liner. It's good for 450F, and I plan on ceramic coating my headers, so the heat load should be well within its margin.
Using heat/sound liner instead.
I mounted the panel itself, but haven't applied the liner yet, since I haven't done the final riveting.
Front Footbox Panel
Firewall Extension Panel
Several mk5 builders have fabricated a firewall extension panel. I thought I could use this panel to support some wiring holes I have planned later.
Several vendors make an extension panel like this, which are really nice products, but I decided this panel was probably easy enough to fabricate myself. So I did a 'stamp' of the relevant frame members:
Firewall Extension Template
Then I cut the panel from my template using a jig saw. Not a pro cut, but it's clean enough for my purposes.
Attachment 227116
Firewall Extension Panel Test fit
Heater Modification
I need a defroster in the car to meet registration inspection requirements, so I've been researching various options. I decided to try a variant of an install that 'ie 427 Garage' did in a youtube video for a mk4, I believe.
I bought a compact, simple box heater from a vendor (I believe this is the same heater ie 427 used), and disassembled it.
My idea for this heater is to mount the blower in the engine bay, and on top of the passenger footbox, and then hang the heater radiator down into the footbox (on the other side of the panel top panel). Then I will create new ports on the side of the heater (leading to the center of the car) and run hoses under the dash, to the various heater/defroster outlets.
I was a bit worried the blower might be too tall for the hood in that area of the car, so I opted to fabricate a new panel for the underside of the passenger footbox frame members. This gives an additional 1.5" headroom for the blower.
I want to still be able to (potentially) mount the coyote ECU in the same general area, so I rotated the blower to run parallel with the dash.
The re-build is almost done, we'll see the final result in week 6.
I took a lot of progress photos of the modification process. I'll explain them in order:
1. Ground down the top of the blower to get just a bit more headroom (probably unnecessary, but easier to do now).
2. Trimmed the base plate of the blower for more flexible mounting options (probably unnecessary).
3. Outline for a new entry hole for the radiator portion, rotated (since the blower is rotated), this will likely effect the heater efficiency, I'm okay with that.
4. Test placing the rubber gasket that separates the blower and radiator box, to determine where to cut a hole in the new mount panel.
5. Cut the new hole in the radiator box
6. Trimmed 0.75" from the radiator box height (x-ed portion) like ie 427 did.
7. Outline for the new (lower) mounting panel.
8. Test fit the new lower mount panel. Notice how it is below the passenger footbox's frame members.
9. Test fitting the blower on the lower mount panel.
10. Side view of the blower test-fit, to check heights and distance from the mounting bracket. I think this should clear the body okay, with the additional 1.5" headroom.
11. Preparing the top of the radiator box to epoxy (high temp) to the new mount panel.
12. I used the gasket to serve as a template for marking the panel cut.
13. Epoxied the radiator box to the panel (post cut).
14. Also riveted the radiator box to the panel, as extra support for the epoxy. Not the prettiest cut, I'm still a bit rough with the jigsaw... I used the 18mm hole saw for my rear-view camera to cut holes for the heater lines (to/from the engine)
15. I cut a new bottom panel for the radiator box (this photo is shown with the box upside-down). Also cut a new side-panel, and epoxied some 2.5" and a 2" output air hose attachment outlets. The original heater had two 3" ports on what is now the bottom panel. These side ports will reduce the heater hose presence in the passenger footbox.
16. Test fit with the mounted radiator box with the blower on top of the footbox. This view is from the passenger seat~ish, the box below the frame member is what will show below the dash in the passenger area. The hot air hoses will run off to the left of the box in this photo (not installed yet)
So far, the heater modification is coming along great. I hope all of the placement locations work out once all of the rest of the car is assembled. I expect to finish the heater mod next week (week 6).
Coming up for week 6
I expect to do some additional sound liner (cabin side) and hopefully get to the steering column that I had hoped to get to this week.
Also I would like to finish the heater modification and get that panel ready to install when I do the passenger footbox.
4 Attachment(s)
Week 6 Update - Heater Customization Complete!
Rebuilding the Heater
It's time to finish the heater customization!
To recap, I fabricated a lower panel for the upper passenger footbox, to mount the heater onto. This lowered mounting point improves the headroom for the blower in the engine bay. I then rebuilt the heater box to be slimmer (took off 3/4"), and also install new 2.5" hot air ports on the side of the heater, rather than the bottom (relative to the the orientation it will be installed in the car). This will afford a smaller intrusion into the passenger footbox (just 3" below the frame bars) and the hot air hoses will run to the left towards trans tunnel.
The heater box's new side and top panels are ready, and it has been epoxied/riveted onto its mounting panel, so the next step is to reinstall the heater radiator portion.
Attachment 227508
Heater Core Reinstalled
I considered installing some new bolt hardware to attach the new bottom panel to the heater, but I decided to just silicone it together (using high temp silicone) since I don't really expect to need to access the internals again, but if I do, the silicone should be manageable to pry open vs. epoxy.
Silicone Sealing Heater Box
Mounting the Heater
After the silicone cured, I scraped it smooth, sanded it down and touched up the paint. Then prepared the top side of the heater to be rebuilt. In these next images, I'm lining up the gasket for the blower with the hole into the radiator box and then riveting the blower onto my mounting panel.
Fitting Gasket on Mounting Panel
Attachment 227509
Mounting the Blower
So far so good! Next I need to install the mounting panel onto the frame, but there's a pretty sizeable gap between the panel and the frame bar, so I cut a section of angle aluminum to patch the hole. I then siliconed it and the mounting panel to the car chassis.
Cut an Angle Bracket
Installed Angle Bracket to Seal Gap
With the silicone in place, I riveted the panel into place. Looking good!
Attachment 227510
Top View Siliconed Mounting Panel
Attachment 227511
Passenger View of Heater (w/o dash)
We can see where the hot air hoses will attach on the left side of the heater box.
I hope there's enough clearance for the windshield mount location, and also around the heater line access, I'm pretty sure they'll work okay. I'm considering creating a small access hatch behind the glove box, through the firewall, to get to the windshield mounting bolts from the cabin of the car, so I don't need to try and reach a wrench past the heater. From what I can tell though, I think it'll be manageable.
Since this is my first build, I'm guessing a bit on where other stuff will go, and what space will be available. If it turns out that the heater as I've mounted it isn't fitting when the rest of the car is in place, I'll grumble and rebuild it -- but I think this placement should work out. Time will tell.
Sound Lining the Heater Panel
I went ahead and put some Damplifier Pro on the underside of the mounting panel, and some Luxury Liner Pro (3/8") on the upper side. Damplifier is rated up to 450F, so it will be fine right next to the heater box. The mounting aluminum panel is epoxied to the original heater plastic box, so it should not transmit too much heat through to the lux liner side (rated to 150F). The heater only gets to 150-200F max, so it should be okay for the lux liner being that close to the heater, but if not, I'll trim some away from the hotter places. I'll do some testing once the heater is functional.
Lux Liner on Top
Damplifier Below
Coming up in Week 7
I didn't get a lot done on the car this week. I tweaked my back out and it took me out of the car building game for a few days, but I'm easing back into it now.
I've started installing the steering column today, so I'll include that in the week 7 report. I also hope to get further on the footbox aluminum and sound liner installation.
5 Attachment(s)
Week 7 - Heater Rebuild Rebuild
Heater Fitment Problem
I began fitting the firewall and footbox panels and discovered that the heater hose outlets would come out into the engine bay more invasively than I had predicted. For a small block engine, this would work fine, but for my Coyote, this has a potential to be a problem. (red marker lines indicate the heater hose route)
Attachment 228004
...So I decided to pull the panel and correct it.
Because the heater is built into one panel, I was able to reasonably easily drill out the rivets and pry the silicone loose.
Then I cut off two of the three heater outlets, and while I was at it, I shorted them.
Attachment 228005
Next, I reinstalled the 2" outlet (for defroster use) on the middle slot, and plugged up the 3rd outlet hole with a circle of aluminum. it's not pretty, but it is behind the other outlets, so it won't be seen (I also sanded and painted it black after these photos).
Attachment 228006
This new configuration means I will need Y-splitters for both the passenger heater vents and the defroster vents. But it does mean the heater hose can pop out much closer to the corner of the engine bay, and then dive back into the above-trans extension where I will mount my heater louvres. The defroster hose (the 2" one) will pop up through a new hole I drilled in the engine bay, directly above the hose outlets, and then through the firewall into the behind-dash area to the defroster-vents. (the image includes a view of the new defroster hole in the panel next to the heater)
Attachment 228007
I'm pretty sure these new outlets and the planned routing should work. Though I will need to figure out a good mounting location for the SPW wiper motor, likely on the driver side.
Drilling and Clecos and Firewall Extensions, Oh My!
I finished out the week doing lots of drilling and cleco-ing on the panels, including installing a simple firewall extension (center, covering the cross-beam above the trans).
Attachment 228008
Coming Up in Week 8!
Next week is build school, but we have some free time on the weekend prior, so we'll be preparing as much sound lining and panel installing as we can.
9 Attachment(s)
Week 8 Update - Sound Lining, Panel Installs and Build School!
Sound Lining Strategy Test (Rear Panel)
My sound lining strategy is almost certainly overkill for most builders. My rationale for going so heavy on the sound lining is that I will be adding the hard top and would like a quiet(er) cabin.
So, nearly the entire cockpit panel set will have three layers of sound lining.
On one side of the panel will be Damplifier Pro (2mm) CLD sound liner. This is similar to some other CLD products like Kilmat and even an amazon basics version. This will generally be on the cabin side of the panels, with some exceptions in the footboxes, where the CLD layer will be on the engine-bay side.
On the other side of each panel will be a stack of Luxury Liner Pro, which is 3/8" deep decoupler and MLV layer in one product. Then on top of that will be 1/2" or 1" (depending on the available depth, generally 1/2") "Mega Zorbe", a light weight sound absorbing foam. All of these products are from Second Skin, but I am not sponsored. I will be using Kilmat for a cheaper CLD layer in the trunk.
The fat stack side (Lux Liner + Zorbe) is intended to go between the frame bars, and will generally potentially be road-facing and subject to debris and water, etc.
To protect these layers from the elements, I will often be covering the exterior frame triangles with carbon fiber veneers. These are scrap carbon fiber (sold by the pound, relatively cheaply), which are thin (< 1mm) and reasonably strong. They also look okay, though a bit mismatched in gloss and pattern.
First I prepare templates for the gap(s) and test-fit them on the panel rear.
Attachment 228013
Attachment 228009
Then I cut out zorbe and luxury liner using the templates (I will be adding the damplifier layer on the cabin-side of the panel much later in the build).
Attachment 228010
Next I glued in (I will add some rivets to support the glue long-term) the carbon fiber back plate. I ran some silicone along the edge of the carbon fiber (from the back side) to seal off most of the inner triangle (though I generally left small draining hole at the bottom and some air gap at the top of the panels, just in case any water does get inside (zorbe is also water safe, so it can handle some exposure, I just don't want any long-term water residence).
After that, I glued the Luxury Liner to the back of the panel, and the Zorbe to the top of the lux liner.
Attachment 228011
Then I siliconed the panel into its final position, sandwiching the fat stack of sound liner between the aluminum panel and the carbon fiber panel, with a small air gap on the carbon fiber side.
Attachment 228012
In the case of the rear test panel, I didn't bother carbon fiber protecting > 12" up the rear wall, because it would be extremely hard to get water or debris up into there, and also the welds made gluing a panel to the top of that frame bar prohibitively tricky.
Attachment 228015
Attachment 228016
Continued in Next Post...
(I ran out of image budget for one post...)
2 Attachment(s)
Week 8 Update - Part 2 - Sound liner continues
... Week 8 continues
Continuing the Sound Lining and Panel Installation
We continued the pattern on the cockpit floors and also on the trans tunnel side walls (part of the cockpit floor aluminum).
I will be protecting the trans tunnel inner fat stacks with carbon fiber paneling later.
Attachment 228017
Attachment 228018
Attachment 228019
Off to Build School!
With the rear and floor of the cockpit lined and installed, we called it a wrap for the week. We will be heading to build school mid-week and learning a bunch about the upcoming steps of the build (and probably some things we missed already).
Coming up on Week 9
We'll be doing some post-build school 'stuff' whatever that happens to be. I assume the school will inspire some immediate action, so you'll need to wait to find out what that is!
