Hundreds Of Products Ready Today. Dispatch/Collection Seats For A Magenta Kit Car: The GT4 Recommendation And The High Back Answer
This week’s question came from a customer rebuilding a Magenta kit car he has owned for a few years. He needs a pair of seats for it, the makers originally recommended the Corbeau GT4, and his one reservation is that he would prefer a high back.
It is the nicest kind of question to get, because the answer is that he can have both. Corbeau still build the GT4, nearly fifty years after cars like the Magenta were being bolted together on driveways, and they still build its high-backed brother, the GT8. Same steel construction, same base, more seat behind your head. This page runs through the two of them, plus the third seat we reach for whenever a kit car comes up in conversation.
- The Corbeau GT4 the makers recommended is still in production
- The GT8 is its high-back brother, on the same base patterns
- Both take a 4 point harness and carry road and track approval
- The narrow Sportsman is the kit car specialist if you want a recliner
- All sold as singles, so a pair is quantity two
The short answer
Buy the GT8. It is the high-back version of the seat the Magenta’s makers pointed you at, from the same Corbeau retro family: rigid steel frame, generous padding, chrome eyelet option, and it was the original flagship Corbeau competition seat, a familiar sight on grids through the seventies. So it is period correct for the car almost to the year.
The part that makes this an easy swap on paper: both seats are drilled for the same two Corbeau base patterns, 291mm x 330mm and 345mm x 271mm. Whatever mounting the makers had in mind for the GT4, the GT8 picks up the same holes. It can be side mounted as well if the build ever goes that way.
The Magenta, briefly
For anyone landing here from a search: the Magenta was a kit car from Lightspeed Panels in the seventies, built in the hundreds, an open buggy-style body over Austin and MG 1100/1300 running gear, with the donor car giving up its subframes, engine and gearbox. Later Roadster and Sprint versions pulled in Ford and Mini parts. They come up at kit car shows regularly and there is a loyal bunch of owners still rebuilding them, our customer among them.
A kit car rebuild is the one seat job where the builder holds all the cards. There is no factory rail to argue with, the floor is whatever the build made it, and the seat gets bolted where the driver actually wants to sit. That freedom is also the catch: the cockpit is usually narrow, and a seat that looks right in a photograph can be two centimetres too wide in the tub. Measure the aperture before falling for anything, ours included.
GT4, GT8 and Sportsman compared
GT4 Retro
The seat the makers recommended, still made. A fixed back retro bucket in black vinyl with the eyelet back panel and an integrated headrest. The period default.
GT8 Highback
The high back the customer asked for. Corbeau's original seventies competition flagship, five harness slots, side or base mounting, same patterns as the GT4.
Sportsman
The kit car specialist. A narrow recliner at 41.5cm maximum width, built for exactly this kind of cockpit, with an optional headrest and a proper backrest adjust.
The honest differences. The GT4 and GT8 are fixed back buckets, so the backrest angle is set once at installation and the seat holds you the same way every drive. The GT8 simply carries the shell up past your shoulders, which is what the customer is after, and its five slot back makes harness routing tidier if the build ever gets webbing.
The Sportsman is a different sort of seat: a steel framed recliner that Corbeau describe as a narrow fit for cars with limited room, at 41.5cm across its widest point. It has lower side support so you can get in and out of a tight tub without gymnastics, and the headrest is a separate part. If the Magenta is being built for long runs out, that adjustability earns its keep.
| Seat | Back | Mechanism | Harness | Price inc VAT per seat |
|---|---|---|---|---|
| GT4 Retro | Standard, integrated headrest | Fixed back | 4 point compatible | £360.00 |
| GT8 Highback | High back | Fixed back | 4 point, five slot back | £510.00 |
| Sportsman | High back, headrest optional | Reclining | 4 point compatible | £468.00 |
Prices include VAT and were correct on 12 August 2026. All three carry road and track approval and sit on steel frames.
-
From £300.00 Excl. VAT Select options This product has multiple variants. The options may be chosen on the product page
-
From £425.00 Excl. VAT Select options This product has multiple variants. The options may be chosen on the product page
-
From £390.00 Excl. VAT Select options This product has multiple variants. The options may be chosen on the product page
Fitting them in a kit car
All three are base mount seats, and the GT4 and GT8 are drilled for both of Corbeau’s patterns, 291mm x 330mm and 345mm x 271mm, so you can bolt them straight to a flat floor or onto runners. On a kit car we would usually put the driver’s seat on runners and fix the passenger seat solid: the runners are about 25mm tall, which is worth checking against your seating position before ordering, because in a shallow tub that extra height lands you in the airstream.
The dimensions drawing on the left is the GT4. Cameron’s advice on any kit car is to measure twice before anything is ordered: the width of the aperture between the sills, the flat floor area the base will land on, and your own head height against the screen or roll hoop with a cushion under you at the height the seat will sit. Ring us with those three numbers and the rest of the conversation takes five minutes.
Two add-ons worth knowing about: the 291mm sliding runner set if you want adjustment, and the Sportsman headrest if you go the recliner route and want the support topped off.
The Tartan editions
Both the GT4 and GT8 also come as Tartan editions, trimmed in a proper 13oz wool tartan across a run of clan patterns with the vinyl bolsters kept for wear. On a seventies kit car rebuild the effect is glorious, and on a Magenta in the right colour it would be the detail everyone at the show asks about. They cost a premium over the vinyl seats, and if you have a particular clan pattern in mind, ask us about it before ordering.
-
From £490.00 Excl. VAT Select options This product has multiple variants. The options may be chosen on the product page
-
From £575.00 Excl. VAT Select options This product has multiple variants. The options may be chosen on the product page
What we would order
For this rebuild: a pair of GT8s in black vinyl with the eyelets, £1,020 the pair. It honours the makers’ original recommendation because it is the same seat family on the same mounting, and it adds exactly the thing the customer asked for. Garreth’s view is that on a fixed back bucket the high shell is worth the extra over the GT4 in an open car especially, where the seat back is part of the silhouette.
The one thing to settle before ordering is width. If the tub turns out tighter than the GT8 wants, the Sportsman at 41.5cm is the fallback, and it brings a recline with it. Measure the aperture, the floor and your head height, then ring Cameron on 0115 9893488 and he will talk you through which shell your numbers point at. Or bring the build over and sort it in person, which on a kit car is usually the quicker way.
Common questions
Is the GT8 really the high back version of the GT4?
Same maker, same retro steel construction, same trim options and the same two base bolt patterns. The GT8 carries the shell higher and adds the five slot harness back. If a GT4 fits your mounting, a GT8 bolts to the same holes.
Will these definitely fit a Magenta?
The makers recommended the GT4, and the GT8 shares its base, so the mounting side is as safe as it gets on a hand-built car. Width is the thing to confirm: measure the aperture between the sills and check it against the dimensions drawing before ordering.
Do the GT4 or GT8 recline?
They are fixed back buckets, so the angle is set at installation. If the build wants a recline, the Sportsman is the narrow high-backed recliner in the same catalogue.
Can I run harnesses in them?
All three are 4 point compatible, and the GT8 has five slots in the back for tidy routing. They also work with a standard belt, and all three carry road and track approval.
How do I order a pair?
GT4 and GT8: quantity two of the same listing, they are not handed. Sportsman: choose an RHD driver side and an RHD passenger side, one of each.
What trim options are there?
Black vinyl or vinyl with a cloth centre on the GT4 and GT8, with the eyelets and an inflatable lumbar as options. The Sportsman adds cloth, leather and piping colour choices. Then the Tartan editions on top for the full seventies statement.