Cockpit/Tunnel Aluminum (rear)

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                                                 GTM AC Compressor Shield >>

Major System Category: Chassis
Task: Install rear tunnel aluminum
Parts: Tunnel Aluminum - Rear (4 pieces)
Prerequisite Tasks: Run all lines inside tunnel (less an issue if you have a lift)
Additional Costs: N/A
Time Requirement: 90 minutes
Date Started: August 24, 2012
Date Completed: August 24, 2012
I started the preliminary fit for the Corvette fuel tanks. These mount behind the seats and ahead of the fuel tank finish panels. I figured out how things fit together and wondered a bit about the lines coming off the bottom of the tanks. About this point I noticed the tunnel panels would be impossible to install after the tanks are mounted.

Driver's side rear tunnel aluminum. I performed a light test looking for leaks in the seams. I found  a couple of places were  air can get through. I used my seam sealer and a spreader to close up gaps along the bottom of the pamels where there is no overlap.

I pulled the fuel tanks out of the car. I need a few things before these tanks are prepped for install. I am a bit reluctant to close up the tunnel, since there are so many things running though there. I also have come tot he conclusion that the AC hoses are too short to comfortably reach the compressor. I read on another blog (I apologize I don't have the link) that another builder ran into the same problem. He found a place that could extend the hose length.

Passenger side rear tunnel panels riveted into place.. I can still access the tunnel from above and below the tunnel.

I decided to sound proof all panels on the cockpit tunnel. I am doing this even though the firewall intersects the tunnel panels. My reasoning is that this is a common panel that could easily transmit heat and sound into the cockpit.I probably will run the heat shield the entire length as well.

Driver's side installed. When the fuel tanks are mounted, all the rivet lines are hidden by the  fuel tank.

Seam Sealing

<< Foot Well Assembly                                                                      Next Link >>

Major System Category: Miscellaneous
Task: Seal seams
Parts: Eastwood Seam Sealer and spreader
Prerequisite Tasks:
Additional Costs: $28 for Eastwood product
Time Requirement: Minimal
Date Started: August 15, 2012
Date Completed:
When I work around the chassis, one of the things I notice are little cracks of light. This has nothing to do with the aluminum panels, riveting or anything that is attached to the car. This is specific to the chassis. If I can see light, then wind and water can move through those cracks as well. One of my neighbors suggested black silicone. A good suggestion, black silicone is already used as a sealer when riveting panels to the chassis or each other. I decided I wanted something to augment the silicone.

Behind the seat and next tot he interior tunnel wall on the passenger side. 

Same area on the driver's side.

A couple of weeks ago, I sent away for a can of the Eastwood Seam Sealer. It is supposed to insulate and waterproof areas. The can says it is brushable, but I found it easier to use a spreader (e.g. like those used for fiberglass). A little bit can go a long ways. Use this product in a well ventilated area, and wear some gloves. It is a gray goop that is spread over the area.

Passenger side foot well inside the inner panel that seals off the evaporator unit.  This is currently dismantled due  to AC work. The driver's side is sealed up, so I plan to apply this from under the chassis as well.

The areas on the chassis I most concerned with are the frame areas in the footwells and behind the seats on the floors. This is where the powder coated floor panel meets chassis cross members. This is not a task that contributes to horsepower or handling. It is  not dramatic like getting wheels on the suspension. It is a task no one sees, and if done right, no one notices. The last thing I want is to be rolling down the road and hear a whistle sound through some gap..

Driver's side foot well. There are a number of rivet seams here and it is forward facing (i.e. a greater chance for wind and water to penetrate the cockpit area)

Same area on the passenger side. This is the outer footwell. One of the few pieces that is still assembled due to the AC work.

 The seam sealer spreads easily and takes about 60 minutes to dry.It can be sanded. Although, this  area will be covered by sound proofing material as well. To me it is more important get things sealed up. Once the sound proof layer and carpet is applied, it is doubtful anyone will nothing minimal differences in the sub surface due to the sealer.

Footbox Aluminum - Passenger Side

<< Driver's foot box                                          Sound Proof Floor >>

Major System Category: Chassis
Task: Build the passenger's foot box
Parts: All parts were attached to chassis on delivery
Prerequisite Tasks: Inner Wheel wells
Additional Costs: N/A
Time Requirement: 4 hours
Date Started: July 13, 2012
Date Completed: July 13, 2012
Consideration: If you are installing, stop now and go to back of the manual and start installing the air conditioning. The evaporator unit must be installed before the passenger foot box is completed.

The passenger side foot box seemed easier to put together than the driver's side. The pieces are different, and there is no fitting around the pedal box. This was pretty straight forward.

This the front wall. Orientation facing forward looking from the passenger area of the cockpit. More than half of this piece connects to the outer wall. The outer wall is not installed, but when installed closes out the right side of the photo.

Once you close in the foot box with the outer wall, it is just a matter of drilling the holes and popping the rivets. I caulked everything heavily with the silicone and sprayed every seam with Plasti Dip. 

You can see the diagonal seam between the front wall and the triangular  shaped panel. This panel serves as an anchor between the inner wall and the front wall. It uses a similar (albeit simpler) interlocking tab concept as on the driver's side. Orientation is facing forward from the passenger cockpit. (You can see the Boxster sitting outside on the driveway.)

I ordered a can of Eastwood's bruashable seam sealer today. This is to address the gaps I see on the underside of the car as well as the some of the areas where the panels have tiny pin pricks. The seam sealer is not supposed to sag, harden or crack. It drys to a dark gray color. I plan to apply a couple of coats, then spray Plasti Dip as an additional layer.

This is the inner wall. Unlike the driver's side, this is one piece. It is  much easier to work with.  Orientation is looking forward from the passenger cockpit area.

The items I am beginning to think about are the sound proofing and heat shield products. Once I get to the point where I have the foot box areas sealed and the floor finalized, I want to put the appropriate materials down to solidify the chassis and reduce the rattle effect.

I call this the funny little connector piece. It is basically there to give the inner wall  an anchor. Orientation is looking from outside the passenger side towards the tunnel.

I need to evaluate  whether I should work on the steering linkage and pedal box prior to mounting the front suspension. Since I am waiting on parts for the shock mounts for the rear suspension, I don't see the benefit of having half the car up on wheels and other half sitting on jack stands.