Front Clip Installation: Part 1

In my last project update the firewall was reinstalled on the birdcage and the body was mounted back to the frame. Next up is the installation of a new front clip!

But, before I jump into the update, here’s a bit of background: Quite a few months ago I spent some time exploring the original front clip and really didn’t like what I found. In addition to lots of minor damage throughout (e.g. mounting brackets broken off, screw holes pulled through, etc.) I also found very extensive areas of shoddy repairs throughout. I call them shoddy repairs because some appear to have been made primarily of some mystery material, while others were made using fiberglass cloth instead of fiberglass matt. In addition, the repairs were all covered in quite a bit of Bondo – another sign that the repairs were less than ideal. Initially, I was planning to repair these areas. However, once I started stripping the paint from the front clip the extent of these issues became very apparent. As best I can tell, my poor Corvette was once in an accident. It appears the car spun catching both the drivers side front fender and the passengers side rear fender (hence the need for the extensive rear clip repairs that were previously completed). After much pondering on how best to proceed I came to the decision to buy a replacement one piece front clip. This was a really tough decision as I really didn’t want to scrap my front clip. Not to mention buying a replacement clip is very expensive. But, after looking over the repairs, quickly estimating my time to repair them, and the cost to have a body shop ‘clean-up’ my repairs, it just didn’t make economic sense to try and salvage the front clip.

The photo below doesn’t do a very good job showing all the issues with the front clip, but I’ve posted it anyway. This is something you really had to see close up so that you could appreciate all of the damage, feel the ‘mushiness’ of the repairs, and generally get a feel for the amount of work that needed to be done.

So, after placing an order for a new one piece front clip, front valence and one replacement inner fender skirt, a large and rather unwieldy box was delivered to my work (they wanted a lot extra to deliver it to my house). I knew the box was going to be big, but seeing the box in person was pretty nuts. Needless to say everyone at work thought I was crazy driving down the road with this huge box hanging out of my truck. But, after tying the box down very securely, down the road I went. Thankfully I made it home with everything in one piece.

Arriving home with my giant box of goodies was the equivalent of being a kid on Christmas morning so I couldn’t help but open up the box right away and look inside. So, here’s what I found. They did a great job packaging everything very securely so all of the pieces made it safe and sound.

As I reviewed each piece I was happy to see the reinforcing strip around the hood was steel – even if it was slightly lighter gauge than the original (I  had heard some replacement front clips came with fiberglass reinforcing strips). However the front nose reinforcing bar was fiberglass. No worries, I ended up swapping it out for the metal one from my original front clip (more on that in a later update).

 

Before digging into my box of goodies any further I decided to leave them packed for safe keeping. So, after setting the box aside, I went to work cannibalizing my original front clip. In order to save money, and as many original pieces as possible, I salvaged as many pieces as possible – the inner fender skirts, mounting brackets, hardware, etc. First on the list were the inner fender skirts.

At this point disassembling bonded fiberglass panels is becoming old hat so I broke out the heat gun and putty knife and set to work. If you’ve never tackled this chore I suggest checking out this how-to video I made by clicking this link: Separating Bonded Fiberglass Panels

 

As you can probably tell, this is the good inner fender skirt that was salvaged. Once the skirt was removed I set to work stripping off all the miscellaneous parts and pieces so everything could be cleaned and painted. The other inner fender skirt was literally in about 5 pieces, was repaired with silicone caulking, and was completely beyond salvage.

Apparently staples were a pretty popular method for attaching weatherstipping and sealant back in the early 70’s. No worries though. I simply cut them in half using a Dremel, pried them loose with a screwdriver, and then removed the two halves using a pair of needle nose pliers. All of these seals were scheduled for replacement which made removal a lot easier and faster – salvaging parts and pieces can be delicate work.

  

Fast forward several steps and I’ve removed the weather stripping, brackets, mounting plates, etc. from the fender skirts, cleaned up the fiberglass with sandpaper and lacquer thinner, and applied a fresh coat of the same epoxy primer used for the windshield frame and firewall (PPG DP90LF). I always find this to be a satisfying step – where you get to see the fruits of your labor. As you can see, the opportunity was taken to paint both inner fender skirts (including the new one which was scuffed up before painting), the freshly sandblasted radiator support assembly, and a few other parts and pieces that will be used to bolt up the front clip. Painting everything the same will ensure all of the body work and frame pieces under the hood will match. It should look great!

 

Once the paint dried it was time to start bolting everything up. To begin you have to start with the front frame extensions, front cross member, and the radiator support.  Each piece was bolted together with the connections left finger tight to allow easy adjustments later on. It’s also worth mentioning that in order to install the front clip you’ll need to have the doors installed – they serve as a reference point while aligning the clip (hint: if you plan to paint the forward door jambs now is a good time to do so).

Following assembly of the radiator support the inner fender skirts were bolted to the radiator support together with the inner fender reinforcement plate. Not surprisingly, the reinforcing plate fit great with the original fender, but not so well with the replacement inner fender. This was mostly due to the fact that the thickness of the replacement inner fender skirt was a bit greater than the original. But, no worries. A bit of quick sanding helped things fit together nicely.

  

Originally the reinforcement plate was riveted to the fender skirts. After several failed attempts at installing new rivets I decided that bolting was a lot easier. Considering the bolts won’t be visible once the radiator and front clip were installed I figured this was a pretty harmless shortcut. To ensure a long lasting connection, self locking nuts were used for these connections.

And here they are – both fender skirts installed and in place. It’s important to know that all of these components need to be installed before the new one-piece front clip can be set in place. Also, at this point the rear of the skirts are loose and sort of just flop around – they aren’t attached to anything yet.

Prior to setting the front clip in place new weather stripping was installed along top of the fender skirts. Although the skirts bond along the edge of the hood opening, and along the side of the fender, there’s no actual attachment between the front and back of the skirt and the underside of the hood surround. So, in order to keep water and debris from getting into the engine compartment, weather stripping is installed along the front and rear edges. Once the front clip (or hood surround) is installed the weather stripping provides a water-tight seal.

Although the originals were stapled in place I decided to secure the replacement seals using epoxy adhesive. To avoid making a giant mess I placed a small bead of adhesive within the groove of the weather stripping by spreading the bottom of the seal open (sort of like a hot dog bun). Next, the edges of the seal were pressed together to distribute the adhesive, the seal was positioned  in place, and a few strips of tape were applied to secure the weather stripping while the epoxy cured.

While the epoxy was curing I diverted my focus to the front clip. A bit of trimming was necessary around the firewall since they overbuild this area at the factory to provide additional stability during shipping. Using a black magic marker the cut limits were laid out based on measurements from the original front clip (the geometry/relief of the fiberglass also makes where to cut obvious) and the excess fiberglass was cut away using a jigsaw. While cutting I stayed shy of the cut line to avoid accidentally removing too much material.

   

Once cut a die girder was used to remove any excess material and to smooth out the rough edges. The final clean-up was completed using a DA sander which I find provides a smoother and straighter finished surface.

Next it was time to level the car side to side and front to back. This is an important step as alignment will affect the final body gaps. I started out by first leveling the rear of the car using jack stands and a few wooden shims to fine-tune the adjustment. I verified the rear was level by using a 3 foot level placed tight to the lower frame cross member (below the gas tank). This provided a large flat area to place the level against and worked quite well.

Leveling the front of the car was a bit trickier. Here the interest is ensuring that the front is level both side to side, and that the car is level front to back. However, there aren’t any flat spots to check the side to side level. So, knowing that the back of the car was all set, I opted to simply verify the car was level front to back by leveling along the underside of the frame rails on the driver and passenger side of the car. Initially the front was raised with a floor jack and shims were placed below the wheels to rough in the alignment. Next, the tires were inflated or deflated as needed to fine-tune the alignment. After a bit of tinkering the car was set and perfectly level in all directions.

At this point the front clip was lifted and dropped loosely into place. Although the clip is relatively light, it’s pretty cumbersome to handle. I suggest getting a second set of hands to help with this effort.

With the front clip set loosely in place it was time to start adjusting the fit. The first step of this process was adjusting the clip front to back. Fortunately, with the original front clip on hand, I was able to determine exactly how much the front lip of the firewall flange needed to extend beyond the front of the firewall (the dimension was determined by looking at the bonding adhesive that remained on the original firewall flange). Basically, I found that the flange should overhang the face of the firewall by 1/16″ to 1/8″. Using this dimension the front clip sat tightly against the firewall flange and the alignment just seemed to look ‘right’ – there was plenty of material to trim along the door gaps, the right-to-left alignment looked ok, and the clip seemed to be square (not rotated) relative to the rest of the car and chassis. So, with the front to rear adjustment roughly ‘set’ one rivet was temporarily set at either side of the firewall to hold things in place while the rest of the alignment was checked out.

The next step included adjusting the height and location of the radiator support which, in turn, also affects the alignment of the inner fender skirts. To do this, measure from the rear hood hinge bolt hole to the front edge of the firewall drip rail. The radiator support needs to be adjusted so that this measurement is 43 inches. This should provide proper hood to front end relationship, and will put the hood in proper alignment with latch mechanisms. If needed, you can wedge a block of wood between the front of the engine and the radiator support (or between the firewall and radiator support if the engine is out, as was my case) to help maintain proper alignment of the radiator support and inner fender skirts.

I also suggest using a floor jack positioned beneath the radiator support to help adjust things – jacking the assembly up causes a rearward rotation at the top of the radiator support while lowering the assembly results in a forward rotation. In addition, the holes for the radiator support are slotted front to back. Up and down alignment will be dictated by the door gaps, rocker panel fit-up (bolt in the rocker panels to monitor the body gaps as you make adjustments), and to align the fan in the center of the radiator shroud (assuming it’s installed). Once you get the vertical alignment set you’ll need to adjust the front to back position of the radiator support to achieve the 43″ dimension. It takes a bit of trail and error to get things right so be patient and take your time.

  

That’s it for Part 1 of the new front clip installation. Another update should be coming in about a month. In the meantime, please stop by the Corvette Restoration Forum to discuss the project, or just to say hi! Lastly, if you haven’t done so already, please Like this project on Facebook to receive the latest news regarding project developments, updates, and progress!