Hood Latches

<< Gas struts                                                         Mount Fog Lights >>

Major System Category: Body (Hood)
Task: Install latches and strikers
Parts: Corvette donor latches/strikers
Prerequisite Tasks: gas struts
Additional Costs: $20 Hood latch rub plates
Time Requirement: 90 minutes
Date Started: September 30, 2012
Date Completed: October 1, 2012
The latch and striker system use Corvette donor parts. There is a driver and passenger side version of the latch. The rule of thumb is that the side with the two square cut outs face front. In my case, the Corvette latch bolts were available. I used those with an extra set of washers on the inside of the body shell.

The side of the body is marked up for the latch install. The Corvette donor bolts are  1/4 inch,  so I drilled the center of the square cuts to give me some latitude to adjust the latch position on the body. Orientation: Driver side latch.

Consideration: It is much easier to do when the doors are uninstalled. The back of the latch can be reached from both the wheel well and door opening.

Corvette donor latch installed, with the Vraptor Speedworks rub plate between the latch and the body shell. I painted my rub plates black. They come unpainted. The square cut outs on the rub plates match the donor hardware.  Orientation: Driver side latch.

I purchased the Vraptor rub plates. These were originally called paint savers. Basically they act as a shield between the striker and the fiber glass behind the hood latch.

This the edge where the hood mates to the body shell. My goal is to keep this aligned. My other goal is to  keep the  left/right and up/down measurements for the hood with 1/8 inch tolerance. These goals do not play nice together.  Orientation: Driver side latch.

Consideration: The manual has this paint marking scheme to figure out the position of the striker. While this might work, it ignores the alignment of the hood and body lines. I developed a different methodology for striker placement.

My method measures from the edge of the body shell to the center line of the latch where the striker  mates. This approximately 9 inches.

My methodology is as follows:

1. Close the hood and ensure the edge of the hood aligns to the edge of the body where they meet towards to top of the door opening.
2. Position the hood latch so it sits in the middle of the up/down and forward/backward. This is so it can be adjusted.
3. On the body, run a measurement from the edge to the center line of the latch. I found this to be approximately 9 inches.
4. Run the same measurement on the hood and project a line perpendicular to the mounting block for the striker. This line aligns to the striker.
5. Duct tape the striker in place and bring it down to the latch. It isn't very easy to see the striker and the latch, but I was able to reach my finger up and feel the location of the striker, then I just lifted the hood to verify the location.
6. Adjust the latch/striker as necessary.
7. Tighten everything down and test latch the hood.

I make a similar measurement with the hood. This one is harder to do because the body shape curves and the mounting block for the sriker is about 2 or 3 inches away from the edge.

The hood is going to want to creep around in terms of fitment. Right now, I am fairly happy with how it turned out. I reran the laser level against the hood. She is still within 1/8 of inch left to right.

Hood mounting

<< Hood Hinge                                                                            Gas Struts >>

Major System Category: Body (Hood)
Task: Mount the hood
Parts: Corvette donor hinges
Prerequisite Tasks: Everything under the hood.
Additional Costs:
Time Requirement: 4 to 5 hours
Date Started: September 26, 2012
Date Completed: September 29, 2012
The task of mounting the hood and attaching the hinges is quite important. Get the hood messed up and the entire car is going to look cockeyed. This certainly requires more thought than just installing the bulb seal, flopping the hood over that and bolting the hinges tot he car. Alignment is very important. Now this isn't to say that if the hinges don't go on just right all is lost. The hood hinges mirror the hatch hinges in that they have some alignment capability.

This is where the hood mates to the body shell on the driver's side next to the  door hinge. The idea here is for the  ends to match up. I found that when i was off by 1/2 inch, this section had slid on me. Once the hinge  is bolted to the hood, this can still be adjusted by moving the hinge assembly where it attaches tot he chassis.

At this point in the build, I am nor ready to seal off the top of the tunnel and run the duct work through holes cut in the top panel. For now the top tunnel aluminum remains uninstalled. However, I did screw the piece that comes attached to the front of the body shell and ran bulb seal over that.

The laser level is an invaluable tool. This is a low light photo, because the garage door is shut and the lights are off.  The horizontal line bisects the headlight pods. This is an easy place to conduct measurements. One thing I discovered is that there no flat spots on the hood. It is a constant curve.

For my initial alignment, I positioned the hood so it runs flush along the body shell where the hood and body meet by the door hinges. I used Gorilla Tape to secure this area. This isn't perfect and things did shift around on me. I set up the laser level and ran the horizontal line so it bisected the headlight pods on both sides. Then I took my yard stick and set it in the pods. Initially, I was half an inch off side to side. The best way to describe the alignment process is to play with the hood until these measurements get within an acceptable tolerance. For me that is somewhere under 1/8 inch difference.

Passenger side light pod.

Driver's side light pod.

I snapped a line under the hood louvers and ran a measurement from the edge of the hood to the louver opening. In this case, everything was dead on. The alignment issues came from one side of the hood being slightly forward of the other side. The laser level is enormously helpful in getting this right. The other thing I did was drop the front end off the jacks so it rested on the suspension and the tires. This helped to eliminate a good chunk of the differences. The rest could be a slight difference in the way I have the shocks set on either side of the car. I am guessing that if I ran the same alignment procedure on my Corvette, I would see similar variations left to right.

The one flat piece I found was inside the front grill. I used a level to see how close I was. She is still a tad high on the driver's side, but well inside my 1/8 inch tolerance.

These are the 5/16 bolts connecting the hinge assembly to the  hood.

Moment of truth. The hood actually opened up. Right now I have a plastic tube holding it up.

I performed a preliminary attachment for the hood. Brought the car back down to the ground and ran the laser measurements over again. I did this a number of times. This is what takes time on this process. I am sure people with more experience can get through this part faster than me.

Hood Hinge

<< Mount Body Shell                                                    Mount Hood >>

Major System Category: Body (Hood)
Task: Mount the hood
Parts: Corvette donor hinges
Prerequisite Tasks: Everything under the hood.
Additional Costs:
Time Requirement: 1 hour
Date Started: September 26, 2012
Date Completed: September 26, 2012
The hood hinge is a combination of the Corvette donor parts and the Factory Five kit parts. The hinge bolts to the mounts at the front of the chassis that sit on either side of the the condenser, radiator and fan assemble inside the inner wheel wells.

Corvette donor hinges. The bumper pads are still attached. The strut mounts for the Corvette struts are pointing up at the bottom of the photos. The Driver is on the left and passenger is on the right.

Factory Five hinge plates.  The Driver is on the left and passenger is on the right.

The build manual photos are pretty good. They show the Corvette pieces, then the Factory Five pieces and then the assembly. I labeled mine D(river) and P(assenger) to keep everything straight. I have adopted this nomenclature for virtually everything in the car. This works better for me than left and right as it is really easy to get turned around.

The Factory Five hinge plate attached to the Corvette hinge. This is the driver's side assembly.

I removed the Corvette struts and left the bumper pad attached to the hinges. I don't think the bumper pads serve any purpose on the GTM. Certainly the strut mount for the Corvette struts are not used.

Hinge assemble attached to the driver's side. Note this is between the inner wheel well and the front tire. The old strut mount is pointing in and the Factory Five hinge plate faces the front of the car. The hinge plate needs to lay flush against the fog light pod inside the hood.

Factory Five uses carriage bolts and nylon locking nuts for the assembly. This proved to be a major help. As I found myself later loosening and tightening things down as I worked to get the hood straight and attached. My trusty ratchet wrench and really long extension got a work out!

Passenger side assembly.

I have to admit I am a little dubious of the long term strength for the hinge to hood connection. The hinge itself is well engineered and can handle the weight. My concern is the fiber glass that the hinge connects to. I estimate the hood weighs around 75 lbs. I've already had one clumsy accident where it tipped over on me and sent my work table cartwheeling into the drive way. The calamity was loud enough for the neighbor across to the street to poke her head out the window to see if I had killed myself or something.

The final task is to attached the bulb seal. The kit has various types of  seals. This is the  one mounts  to the top of aluminum. It has a sleeve that slides over the edge of an aluminum panel. In this case the inner wheel well.

The nice thing about the hinge set up is there is room for error and correction. The manual says not to tighten down everything, but sooner or later the time comes to raise the hood and see if things hold together.

Donor Parts vs. New Parts

It is much cheaper to go the donor car/parts route. I asked Factory Five Tech Support about going the C6 route with a donor car. Factory Five said the donor car has to be a C5. This basically ended my idea of going with a C6 as a donor car and salvaging a LS3 engine.

The other issue I have wrestled with is a new car build with is used car parts. Do I really want to put used parts on a new car? I think I have come up with a reasonable compromise on this issue. I will probably go with a donor parts kit from Fparts for the suspension, cooling system, e-brake, full delivery and miscellaneous parts. Anything that seems really hacked up will get replaced with new. I have also inquired with Fparts about the possibility of getting the telescoping steering column and the newest version of the fuel tanks as part of the donor parts kit.

I intend to spend close to 40% of the build money on a brand new engine, transmission, A/C, big brakes, big wheels and upgrades to the interior, instrumentation, electronics and lighting. If I am going to build a car capable of approaching 200 mph speeds, then I am going to make sure the drive train and power plant are up to the task.

The other reason for going with this approach is the story of Vern and his Miata. He had this beautiful little red Miata for twenty plus years. He knew every bolt, quirk, screw and sound the car made. When the car was totaled in an accident in 2010, Vern was bummed out. I asked him why not pull the new stuff he had just put on the car and get one of the same vintage. Those cars were only running about $5000 to $8000. Vern shook his no, explaining that he wouldn't know what had been done to the car. He knew everything that had been done to his car.

The GTM build is a unique opportunity to know the car right down to the last bolt. So next month, I plan to pull the trigger and purchase the donor parts kit. It will take me a couple of months to get everything cleaned up. Meanwhile, there is the new front end for the Boxster and the Z51 sway bars for the Corvette...