Submitted by: 69MyWay
This topic comes up often, so I thought I would share what I have learned with others considering the mod.
Thanks to John AKA Black Thunder I have had the awesome opportunity to install a set of 1994 Corvette seats in my 69. There are some minor differences in the 94 seat from the 84-93, but the basic seat bucket and frame is the same.
To do it how I did it, you will need some good hacksaw blades, drill bits, 5/16" thread tap, a hand full of 5/16" bolts, and some raw stock 3/8" thick by 2" wide steel plate, and good dremel tool with bit.
First, I bolted the stock C3 tracks into the floor of the car. I then removed the lower cushion of the C4 seat and placed it in the car over the stock C3 track. I was able to use the factory C4 front bolt holes with a slight amount of dremel work to widen them by about 1/8".
I took it all back apart and then cut two 4" long pieces of the steel plate. I drilled and tapped the 5/16" threads and mounted it on top of the rear seat track frame on both sides. What this did is raise the mount up, and give me a wider mount to bolt the seat frame to. In the front I made two small blocks from the same plate, drilled and tapped them, then ran a bolt up like a stud from the seat track.
Okay, I put the seat back on the tracks bolted on the floor, and lined up the front holes on the bolt studs sticking up into the stock C4 holes that I had dremeled out just a tad. I then marked the bolting plate in the rear through the stock C4 mounting holes.
I pulled it all back open, took the rear mount plates off and drilled out the marked hole. Another quick trip to the drill press and tapped out those holes with 5/16" threads. I had to custom cut the length of the bolts so they would not extend beyond the mounting plate and snag the track below.
Back to the car. I mounted the rear plates on the tracks, front spacer plates holding the bolts like studs, bolted the tracks to the floor, then sat the seat over the front studs, wiggled and lined up the rear mounts and ran bolts down through the seat frame into the mounting plate.
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Article ID: 810
Created On: Tue, Aug 5, 2014 at 1:32 PM
Last Updated On: Tue, Aug 5, 2014 at 1:44 PM
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/1968-1982-corvette-installing-c4-corvette-seats-in-a-c3-corvette-810.html