Obscure C3 Modifications
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 29
Likes: 2
Obscure C3 Modifications
Hello,
I'm more of a lurker than poster, but I'm going on year 7 of C3 ownership and I wanted to ask if anyone has ever done any of the following projects/modifications
converting 78-82 doors to 68-77 style ( the linkage is different per year, but I think the earlier corvettes have way better interior styling especially the door panels.
modifying the floor pans to sit lower flush with frame (allows more options for tracks and aftermarket seats without losing room)
modifying any part of the frame to aluminum, especially the front battering ram or rear bumper supports and gas tank area.
running a lighter weight modern steering column
thanks in advance for anyone who can link me to any of their projects
I'm more of a lurker than poster, but I'm going on year 7 of C3 ownership and I wanted to ask if anyone has ever done any of the following projects/modifications
converting 78-82 doors to 68-77 style ( the linkage is different per year, but I think the earlier corvettes have way better interior styling especially the door panels.
modifying the floor pans to sit lower flush with frame (allows more options for tracks and aftermarket seats without losing room)
modifying any part of the frame to aluminum, especially the front battering ram or rear bumper supports and gas tank area.
running a lighter weight modern steering column
thanks in advance for anyone who can link me to any of their projects
Last edited by CombatBaby; May 20, 2020 at 01:32 PM.
Tech Contributor
Joined: Jun 2004
Posts: 20,905
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Hello,
I'm more of a lurker than poster, but I'm going on year 7 of C3 ownership and I wanted to ask if anyone has ever done any of the following projects/modifications
converting 78-82 doors to 68-77 style ( the linkage is different per year, but I think the earlier corvettes have way better interior styling especially the door panels.
modifying the floor pans to sit lower flush with frame (allows more options for tracks and aftermarket seats without losing room)
modifying any part of the frame to aluminum, especially the front battering ram or rear bumper supports and gas tank area.
running a lighter weight modern steering column
thanks in advance for anyone who can link me to any of their projects
I'm more of a lurker than poster, but I'm going on year 7 of C3 ownership and I wanted to ask if anyone has ever done any of the following projects/modifications
converting 78-82 doors to 68-77 style ( the linkage is different per year, but I think the earlier corvettes have way better interior styling especially the door panels.
modifying the floor pans to sit lower flush with frame (allows more options for tracks and aftermarket seats without losing room)
modifying any part of the frame to aluminum, especially the front battering ram or rear bumper supports and gas tank area.
running a lighter weight modern steering column
thanks in advance for anyone who can link me to any of their projects
I have a bolt-on aluminum front crossmember 80% done (I'm running a C4 suspension under the car) to eventually replace the previous steel crossmember I fabricated several years ago.
I made the transmission crossmember in aluminum.
Years ago I transplanted a late C3 batwing onto my '69 (15# off the car), but more recently I adapted a C4 D36 batwing to fit my differential, for an additional 5# off the car.
Have considered making the rear section of the frame in aluminum (like a C4), but I don't have a rear section handy to make a jig from. I don't want to cut the rear section off the current frame (stock frame is safely stored away) yet, as that would keep me from driving the car until I finished the aluminum replacement.
I've looked around for a lighter steering column, but haven't found one yet that looks like it would package well and look somewhat natural in the car (I like a light car, but I also like the stock/sleeper look).
Burning Brakes
Joined: Feb 2014
Posts: 1,045
Likes: 226
From: Cape Neddick Maine
2020 C3 of the Year Finalist - Modified
I did that to my 76 someone put newer doors on my car so it had the ugly door panels. It was not too bad to swap out pretty much just change out the door rods and handles. The door lock mechanism was also different. Make sure you use the correct weather stripping around the door to match the door panels.
I believe the brackets all had to be removed from the newer door at the spot welds. The newer doors still have the holes for the interior door handles, I used nylock nuts to secure them to the door.
The exterior door locks needed to be removed to change out the mechanism for the rods to attach to. and the other rods need to be changed to the early style. If I had to do it over I would it was not a big deal to do and mad the car look correct to me.
Mine had Oyster cloth on the door panels and the clam shell seats. and everything else in oyster. I went back to the original Deluxe Buckskin interior but used C5 seats, much better to me than the clamshells. The clamshells always seemed to be reclined back to much for my liking. I still need to change out the 77 only steering column wish I knew why Bubba was here especially for a car with only 78k original miles....oh and it had 4 paint jobs the original Brown then Maroon and Dark Blue twice.
I believe the brackets all had to be removed from the newer door at the spot welds. The newer doors still have the holes for the interior door handles, I used nylock nuts to secure them to the door.
The exterior door locks needed to be removed to change out the mechanism for the rods to attach to. and the other rods need to be changed to the early style. If I had to do it over I would it was not a big deal to do and mad the car look correct to me.
Mine had Oyster cloth on the door panels and the clam shell seats. and everything else in oyster. I went back to the original Deluxe Buckskin interior but used C5 seats, much better to me than the clamshells. The clamshells always seemed to be reclined back to much for my liking. I still need to change out the 77 only steering column wish I knew why Bubba was here especially for a car with only 78k original miles....oh and it had 4 paint jobs the original Brown then Maroon and Dark Blue twice.
Le Mans Master
Joined: Oct 2000
Posts: 6,362
Likes: 30
From: Oak Harbor WA
Modifying the floor pans so you can lower them to be equal with the frame will not work out very well if you want to have the exhaust run under the chassis like the stock systems do. There needs to be plenty of room for air to move around for cooling.
Now, I'm not sure of the complete impact if the car is running a side pipe exhaust. However, that would likely force that decision to be made. I think there might be thinner seats coupled with lower seat mounting hardware that could do much of that without replacing the floors....
The idea has crossed my mind a time or two as I am over 6ft tall.
Now, I'm not sure of the complete impact if the car is running a side pipe exhaust. However, that would likely force that decision to be made. I think there might be thinner seats coupled with lower seat mounting hardware that could do much of that without replacing the floors....
The idea has crossed my mind a time or two as I am over 6ft tall.
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 29
Likes: 2
Modifying the floor pans so you can lower them to be equal with the frame will not work out very well if you want to have the exhaust run under the chassis like the stock systems do. There needs to be plenty of room for air to move around for cooling.
Now, I'm not sure of the complete impact if the car is running a side pipe exhaust. However, that would likely force that decision to be made. I think there might be thinner seats coupled with lower seat mounting hardware that could do much of that without replacing the floors....
The idea has crossed my mind a time or two as I am over 6ft tall.
Now, I'm not sure of the complete impact if the car is running a side pipe exhaust. However, that would likely force that decision to be made. I think there might be thinner seats coupled with lower seat mounting hardware that could do much of that without replacing the floors....
The idea has crossed my mind a time or two as I am over 6ft tall.
I'm 6'4 and been playing with the idea of lowering the pans for about 6 years now. I've machined custom brackets for my sparcos and it works, but honestly I want to put the seat sliders back in to make the tilt and slide for getting to the rear storage easier. Only lowering the pan will do that at this point. Heat shouldn't be as issue. Can always put more heat shielding around there.
Thread Starter
Intermediate
Joined: Jul 2013
Posts: 29
Likes: 2
I did that to my 76 someone put newer doors on my car so it had the ugly door panels. It was not too bad to swap out pretty much just change out the door rods and handles. The door lock mechanism was also different. Make sure you use the correct weather stripping around the door to match the door panels.
I believe the brackets all had to be removed from the newer door at the spot welds. The newer doors still have the holes for the interior door handles, I used nylock nuts to secure them to the door.
The exterior door locks needed to be removed to change out the mechanism for the rods to attach to. and the other rods need to be changed to the early style. If I had to do it over I would it was not a big deal to do and mad the car look correct to me.
Mine had Oyster cloth on the door panels and the clam shell seats. and everything else in oyster. I went back to the original Deluxe Buckskin interior but used C5 seats, much better to me than the clamshells. The clamshells always seemed to be reclined back to much for my liking. I still need to change out the 77 only steering column wish I knew why Bubba was here especially for a car with only 78k original miles....oh and it had 4 paint jobs the original Brown then Maroon and Dark Blue twice.
I believe the brackets all had to be removed from the newer door at the spot welds. The newer doors still have the holes for the interior door handles, I used nylock nuts to secure them to the door.
The exterior door locks needed to be removed to change out the mechanism for the rods to attach to. and the other rods need to be changed to the early style. If I had to do it over I would it was not a big deal to do and mad the car look correct to me.
Mine had Oyster cloth on the door panels and the clam shell seats. and everything else in oyster. I went back to the original Deluxe Buckskin interior but used C5 seats, much better to me than the clamshells. The clamshells always seemed to be reclined back to much for my liking. I still need to change out the 77 only steering column wish I knew why Bubba was here especially for a car with only 78k original miles....oh and it had 4 paint jobs the original Brown then Maroon and Dark Blue twice.
The bright side to this is when I get around to pulling the doors off the body I'll be going in there anyway to eliminate all rust so I'll be able to swap some linkage. Good to hear it can be done well, even if super tedious
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Thread Starter
Intermediate
Joined: Jul 2013
Posts: 29
Likes: 2
I swapped out the radiator lower crossmember and support for aluminum substututes. Made jigs from the original parts, and then fabricated the lighter weight parts. A coat of semi-gloss black for the stock look, and not one person has noticed the difference.
I have a bolt-on aluminum front crossmember 80% done (I'm running a C4 suspension under the car) to eventually replace the previous steel crossmember I fabricated several years ago.
I made the transmission crossmember in aluminum.
Years ago I transplanted a late C3 batwing onto my '69 (15# off the car), but more recently I adapted a C4 D36 batwing to fit my differential, for an additional 5# off the car.
Have considered making the rear section of the frame in aluminum (like a C4), but I don't have a rear section handy to make a jig from. I don't want to cut the rear section off the current frame (stock frame is safely stored away) yet, as that would keep me from driving the car until I finished the aluminum replacement.
I've looked around for a lighter steering column, but haven't found one yet that looks like it would package well and look somewhat natural in the car (I like a light car, but I also like the stock/sleeper look).
I have a bolt-on aluminum front crossmember 80% done (I'm running a C4 suspension under the car) to eventually replace the previous steel crossmember I fabricated several years ago.
I made the transmission crossmember in aluminum.
Years ago I transplanted a late C3 batwing onto my '69 (15# off the car), but more recently I adapted a C4 D36 batwing to fit my differential, for an additional 5# off the car.
Have considered making the rear section of the frame in aluminum (like a C4), but I don't have a rear section handy to make a jig from. I don't want to cut the rear section off the current frame (stock frame is safely stored away) yet, as that would keep me from driving the car until I finished the aluminum replacement.
I've looked around for a lighter steering column, but haven't found one yet that looks like it would package well and look somewhat natural in the car (I like a light car, but I also like the stock/sleeper look).
Any pics of that aluminum cross member? I never considered it doing much for the frame as much as it does for the transmission or an unsupported exhaust.
The rear bumper and crash beam system is probably a must have for me at this point. Got up in there with my scope and took pictures from the bottom. There's plenty of surface rust and areas I can drop weight going with aluminum or composites.
In 2020 I'm not too concerned with the 5mph impact anyway....with all the trucks and SUVs on the road I'm going under another vehicle and that's what I have life insurance for.
Tech Contributor
Joined: Jun 2004
Posts: 20,905
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
