1989 C4 Functional Restoration

[SirReal63]

Ive never been a fan of Corvettes, but I can appreciate all your hard work and knowledge that went into your restoration--Plus I love a good build thread! Sub'd

I was always a fan of the older Vettes, after the C4 I lost interest in them. The C4 was such a ground breaking car, it destroyed everything in stock form. Banned from SCCA showroom stock class and had to have it's own race for a few years until the rest of the world caught up.

 

[SirReal63]

I decided to focus on the hood the past couple of days as I knew it was not in great shape. I bought a new heavy cut pad and compound from Menzerna as I was running low on 105 and only had one old cheap heavy pad from SPTA. Surprisingly the cheap pad was courser than the new pad and cut faster.

New Menzera heavy pad on the left and old SPTA pad on the right, same Menzerna 1000 compound.



I have been using Maguires for a few decades and had really no complaints but I was ready to try something different. After considering more brands than anyone should have to I gave the Menzerna line a try and I will be using their products from now on. Unlike the 105/205 compounds this doesn't dry fast, doesn't cake up and clog the pads and removes easily. It has no silicones and works fast, because it doesn't dry fast you end up using way less product and pads last longer before needing to be cleaned. Sometimes change is good.

The difference between one pass with the heavy cut and 5000 grit paper. Compound on the left...



I was/am really concerned with the thickness of the clear on the hood, my paint depth meter does not work on fiberglass so I am flying completely blind. There are some scratched that I am justnot going to worry about, they look like a cat slid down the hood at some point. I could absolutely sand them out but the danger of blowing through the clear is just too high. I will live with them. The rest of the pics are all of the hood.

First pass with the heavy pad on the hood which was lightly sanded with 2000-5000 before the compound.



I used a LED light for the next shots and learned it doesn't work quite same with metallic as it does with solid colors. I had to try and hold the light exactly the same in relation to the camera to get it to show the differences. All of these are about the same spot with about the same angle. This was a progression from the 1000 compound to 2500 to 3800.






The flash really brings out the metal flake.









The cat scratch area. It bothers me but you really have to look for it to find it.






These are various overhead shots in progression from the 1000 compound to the 3800. Pay attention to the light in the lower center, the rest are off angle photograph blurry, dang metal flake.
























Frontal shots, it came out better than I had expected. I will still go over this with swirl remover which should brighten it up a little.







Now I have to make the rest of the car look at least as good as the hood, my poor arms. lol

 

[SirReal63]

The pressure is on since I did this car with spray cans, it is direct reflection on me (pun intended) if it looks like crap when I am done.

I am mostly surprised at the hood, it really looked bad before. I am going to have to spray this in the Spring, the color difference, though slight, really bothers me.

Before sanding and with only one pass with 105, very hazy with no clear definition.



After buffing, the white horizontal lines are actually the roof joists above it, the reflections are wild. The color did darken slightly but I don't think it is enough, I will know the next time it goes outside.



I has been a daily task, I could only run the buffer a few hours a day as the vibrations give my hands fits. I could only hand sand an hour or two at a time with an hour or so break in between.

 

[SirReal63]

A small update but I have been busy with sanding and priming. The car had an annoying gap between the passenger side hood and the bumper cover. It bothered me but there were so many other things to do I left it alone. It became more of a priority while buffing out the hood so I decided to dig into it.

The problem, I cannot believe I never took a good pic of this...












I found all of the nuts/bolts/shims that make up the alignment and made them all loose enough to move the bumper cover around. I could get it pulled mostly into place but when I moved it down it also moved it out, making a large gap. I removed the 3 shims, 2-thick and one thin and that made it way too close, so I added the shims back one at a time, one thick and one thin made it the right gap. Putting the shims back in was more than just hard, it was almost impossible with everything attached. I improvised a skinny hand to help guide the shims into place, a piece of mono-filament fishing line taped to the shims which were also taped together. This worked beautifully as I could maneuver them into place on top of the studs they fit on. There was no way to do this with everything attached.






The alignment is not perfect, but it is the hood sitting low on the passenger side. I will add the correct shims once I gather some, for now it will work just fine. I am not sure I can make the gap consistent across the length of the bumper cover, there does not appear to be enough adjustment across that length to correct it. Perhaps if I remove the entire cover I can shim each little bolt along the length to get it closer but after seeing what all has to be done to remove the cover it has become a low priority item. I have bigger fish to fry first.

 

[SirReal63]

On to bumper "repair". I have no idea why someone previously tried to smooth out the rear bumper. Whatever filler they used was applied too thick and appears to have shrunk which caused the paint issues. I chipped out all of the filler and paint, sanded it smooth and discovered a couple small high spots and a couple low spots on an otherwise smooth and flat bumper cover. There were a few deep (ish) scratches that got sanded and filled with the UV putty after priming. In reality this bumper cover isn't in bad shape but the previous repairs were not done very well and overdone for no reason I can find. I used a stainless 12" ruler to check for high and low spots and got them back almost perfect. I don't expect perfect here, there is no reason to shoot for that on this car.






There were also some cracks under the license plate that look like some used it as a step but they do not go all the way through the cover but they did crack the numerous layers of paint. For fun, count the paint layers.

I sanded down enough that I could fill the cracks and sand most of it out. This repair should last as long as no one uses it as a step.










The front passenger side in process. I thought I took more pics of this in process but I did not.



Primer applied and sanded. I went with epoxy primer instead of urethane primer. I read the pros and cons of each and in the end settled on the epoxy. I hope it wasn't a mistake but then again I would say the same if I went with urethane as either appear to work and/or fail.









First dusting of paint...

 

[SirReal63]

Bumpers painted...






Clear going on...












I had managed to burn through the clear in one tiny spot on the trunk where a gnat had landed area so I shot it again. It is sanded down here and somehow I worked right through it without taking more pics, though they are not needed, I boo boo'd and had to fix it. It is embarrassing to make a mistake but I did and that is what learning is all about.

The sanding was not fun, I did it mostly by hand as the courser grits can pigtail. This was after everything was roughed in to 2000 and then 3000 grit.












Finally down to 5000 grit...









I am currently buffing but am taking my time with it, the vibration really messes with my arms.

 

[SirReal63]

Paint conclusion (mostly) and pic heavy.

I am mostly done with paint for now. I still need to work on the bumpers, they will need another coat of paint to get closer to the color of the rest of the car. Since I applied to paint over a light colored primer it did make the final color lighter. This was intentional and desired on the front where the bumper top meets the lighter in shade hood. I made it too light for a good match but it is easier to add paint to darken than to remove. The rear is actually close but there is a metal flake direction issue where one spot got too much paint at once and the flake rose up, an easy fix but I did not catch it. The car is buffed and the reflections are ridiculous and difficult to photograph the repair areas, or any close up shots of the paint. It is like trying to photograph the silver backing of a mirror, all you see are reflections.

I did body color the door handles and pin escutcheons. It was a small gamble as the pin escutcheons are easily removed to paint back to black and the door handles can be easily masked. I actually like it, I was afraid I would not, but I do, it looks cleaner to me. I put a lot of clear on them in hopes of protecting them from scratching and may also use some 3M Clear Paint Protection Film on the escutcheons to keep the pins from scratching them as easily. I think they turned out OK but the the recess they fit in makes it look like a halo around them in photos from the flake direction change, they eye doesn't see it the same.

The handles and escutcheons in process and finished...
























The rear bumper repair in process and all buffed out...

 

[SirReal63]

Some outdoor shots of the mostly finished product...







































The goal was a 10 to 20' improvement and I surpassed that I believe. There are some areas that need refinement of the paint as some small scratches are visible at the right angle but that can be done after I recuperate. Once everything has cured in a few months I will probably go over the whole car again with the varying grits of compound and refine any remaining imperfections missed this time around.

I cannot complain, the before and after shots tell a story...











It has taken me a year to get to this point, so much done and still so much to do.

The partial list for the next year...

Finish the bumper paint to get a better match.
Replace A/C Condenser and hoses and get that system back in order.
Drop exhaust to wrap it and replace temp gauge wire that is burned and corroded.
Refinish the stock 89 wheels and get them back on the car.
Replace the ECM with a better system that is far more user friendly to get the idle correct. Either Holley or FiTech or other.
Replace shocks and possibly springs. The car sits too low at about 26.5" to bottom of fender well. I scrape on everything.
Replace the leather on footwell with the correct carpet as I found I can buy just the pieces I need.
Replace steering wheel.
Replace heads and cam after ECM is on the list but still investigating the right combo.
Replace headlights.
Take several mini vacations.

I am sure there is a lot more but so far that is the main items on the list.

 

[SirReal63]

I took a pic on an overcast day before the rain came. It does photograph better in the shade without bright sun on it and shows the color better. The hood is still obviously a lighter shade but the rest on the same plane is consistent, though the reflections still make it hard to show the color match. I'll take it and be happy with everything but the hood. I commend Paintscratch dot com for getting me consistent colors over 3 orders.



.

 

[SirReal63]

I decided to tackle the hideous Janus shop doors and get them sealed and insulated. This should help with the temps in there this Winter as I hope to be out there more than normal. I learned my lesson with trying to do epoxy work in cold temps, the 24 hour set up time was not going to happen again.

Back in 2016 when I built this place I already knew these doors were horrendous. The top of the doors left a large gap that wind and dust blew through. If I had known just how bad it was I would have made sure we got a better door for the shop. Live and learn and fix what you can. I found the "sealing" kits for these doors but they were ridiculously priced and didn't really help with insulating. Initially it was the large gap at the top that was the pressing issue.

The problem as seen from the outside looking up from 2016, that plays into the recent fix...



The problem as seen from the inside over the door looking down, this is what I need to be able to seal enough to stop the wind from blowing into the shop. The problem is the size of the rolled up door changes when it is rolled up as opposed to rolled down so the sealer has to be flexible, able to adapt to the changing door size and seal when the door is down, and it has to last since I will have limited access once the ceiling is up.




The solution was to cut strips of 2" polyester batting like is used in seat cushions, not the loose stuff but the solid formed stuff. With the door down I measured how much would be needed to fill the space, slightly compressed, and cut it to fit and used a ripped 2x4 with metal screws to hold it down. Because the stuff is very flexible it pulls up out of the way when the door is open and the ribs in the door pull it down to fill in the void when the door is down.

Inside looking down...



Outside looking up...



The space is filled, will block the wind from blowing in and is hidden from view outside unless you are standing at the door looking up. It does not stop all air infiltration, but that wasn't the goal, these doors aren't sealed in any way, especially on the edges so I didn't worry about trying to make it a weather tight seal. This has met the need and the stuff should last decades.

Back to the present, the fix from above did stop the wind, dust and birds from getting into the shop but did nothing to help with the air leakage on the sides and temp exchange from only a thin piece of metal between the sun/cold and the shop. I had considered using Frost King on the interior of the door, but since this is a roll up door, anything added to make it thicker will also make the size of the drum larger when rolled up, that is an issue for obvious reasons. I decided to insulate the doors in a different way, 1" foam insulation and a wooden frame and I could block off the metal from being directly connected to the interior space. There is a wooden frame around the Janus doors from being framed in for 10' ceilings. I cut the foam to fit tightly around the bottom and sides of the wall framing, this gives me a good weather seal from wind getting around the door sides and bottom. I used removable pin hinges to make it so the doors can be removed if and when needed. It came out as I expected, the wood frame is panel bonded and sandwiched between two layers of wood to keep it together. There is already a huge comfort difference in the shop.






A knife latch and cane bolt keep it securely in place.