Real Race Seats 70 Litre Poly-Bead Resin Seat Insert Kit Real Race Seats 70 Litre Poly-Bead Resin Seat Insert Kit £349.54 Incl. VAT£291.28 Excl. VAT

Real Race Seats 40 Litre Poly-Bead Resin Seat Insert Kit

£231.40 Excl. VAT

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Real Essential seats are made by positioning the driver on a liner filled with micro poly-beads and a slow cure resin. The kits are designed to allow the driver to ensure the optimum seating position is achieved by displacing the beads and resin mix (mix features black pigment to ensure best results) in the liner. Mixing the kit is a straightforward process of using the mixing bottle (included) for optimum results. Curing is achieved by applying a vacuum via an attached valve (using a Vacuum Pump And Hose, see Accessories), allowing the liner to be formed to the desired profile and shape, which is then maintained throughout the curing process.

Works best as an infill for a single seater extractionseat such as A1GP, F2 AND WSR or Formula Ford.

  • Complete Kit For DIY Manufacture
  • Makes A Seat That Fits You Perfectly
  • Curing Is Achieved By Applying A Vacuum
  • Gives Increased Comfort, Safety And Durability
  • Comes Complete With Full Instructions

Race proven poly-bead seat resin kits include the following:

  • Black colour pigment to ensure confidence when mixing the resin with beads
  • Resin and hardener semkit (mixing bottle) which is simpler, cleaner and easier to use
  • Fire retardant, anti-bacterial brushed nylon fabric and spray adhesive for covering seat insert

Although preparation and curing time is longer than 2-part foam, the advantages are well worth it! Users have time to test various seating positions before adding the resin to ensure they achieve the best seating position which can then be replicated once the resin is added and mixed. These seat infills offer increased comfort, safety, and durability.

Brand

Litre Size

In-store displays:

We have a premium range of over 125 seats from brands including: Bimarco, Cobra, Corbeau, Sparco, OMP, Recaro, GP-Race, and Bride to name just a few brands we work with.  

Alongside this, we also stock and display HANS devices, harnesses, race-wear, race-suits, FIA helmets and various other safety equipment. If you are looking to visit us to see and try any particular seat or product, please contact us in advance and we’ll be happy to help.

In-Store appointments:

Book now!

Due to the specialist nature of our services, we do ask that you please contact us in advance to book an appointment. We have multiple slots available each day including selected availability at the weekend.

Working by appointment allows us to dedicate our time with you and provide a personal and professional service. We’ll always ensure you leave with the right equipment for your needs.

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Fast delivery lead times:

If you require fast delivery, please contact us in advance of ordering and we’ll happily check stock allocation and availability for you. We carry a large amount of stock at our showroom and across multiple distribution hubs. This allows us to provide immediate dispatch across a huge number of brands from Corbeau and Cobra through to Sparco and OMP. (Does not apply to all items)

Due to the niche market we work in, some products are custom hand made to order, or special order from manufacturers like PCI Racing and Planted Technology. If you want to know how fast a product will be dispatched. Simply drop us a message through our Contact us form.

ParcelForce

Addtional lead time notes:

Quick dispatch: Stocked products are dispatched within 24-48 hours with Parcel Force.
Sparco roll cages: We can only deliver these to a registered (LTD) company address.
In-store collection: Please contact us in advance to book an in-store collection appointment.

Availability

We stock a wide range of the Real Race lumbar support pump up cushions in various sizes. These can be made available for dispatch within 24 hours. 

Specicalist components: Various materials and specialist components are directly sourced from the manufacturer to order. This direct delivery method means that most in stock parts are delivered within an estimated 7-10 days. 

Need them fast?  Please contact us in advance to check our stock and product availability. we may be able to dispatch them within a shorter lead time. Speak to us in advance to find out how we can assist.

Seat insert kit and cushion guide

These are the two ways to change how a seat fits after you have bought it. A cushion changes your height in the shell. An insert kit moulds the shell to your body. They solve different problems.

Which one do you need

If the seat fits but you sit too low or too high, you want a cushion. If the seat is the right size but you move around in it, or it is a size too big and you want it to hold you properly, you want an insert kit.

Seat cushions

Sold as low, medium and high, and the name is the cushion thickness rather than anything about the seat. It is the cheapest way to fix a driving position that is nearly right.

Type What it does Who it suits
Low cushion Drops you as far into the shell as it goes Tall drivers, and anyone short of helmet clearance
Medium cushion The standard Most drivers, most cars
High cushion Lifts you up in the shell Shorter drivers, and better vision over the bonnet
Check headroom before you go upA high cushion lifts you toward the roof, and in a car with a cage and a helmet that is exactly where you have least room. If you are close, measure before you order. Going the other way, a low cushion is the first thing to try if your helmet is touching.

Most of our cushions are made for a specific seat, currently the Mirco Classic, GT, RS1, RS2, RS7, RTS-2 and RTX-7. Check the compatibility on the product, because a cushion cut for a different shell will not sit right.

Seat insert kits

An insert kit is expanding foam and a bag. You sit in the seat, the foam expands around you, and it sets to the shape of your body. It is what single seater and rally teams use to make one shell fit one driver properly, and it is the answer when a seat is a size too big.

Sold for Litre size What it suits
Small drivers 30 to 40 litre A slim driver in a standard shell, or filling a small gap
Medium and small drivers 40 to 50 litre The usual starting point
Large and medium drivers 50 to 70 litre More material, for a bigger gap or a deeper shell

The litre figure is the volume of foam in the kit, not a measurement of you or of the seat. More litres fills a bigger gap. If you are between two, the larger kit gives you room to get it right, and you can trim the result.

You get one attemptThe foam sets once. Read the instructions properly, have someone to help you, and be dressed exactly as you will drive, in your suit, with your helmet and your head restraint on and the harness done up. Any layer you leave off is a gap you will feel every time you get in afterwards.

FIA 3795:1992

Six of our insert kits carry FIA 3795:1992, which is the standard for the foam itself. If you are running in a championship that requires an approved insert, check for it on the product. The rest are for road, track day and club use where no approval is required.

A note on sizing up and padding out

If you are between two seat sizes, our advice on the bucket seat guide is to take the wider one. An insert kit is what makes that advice work. A seat that grips your hips cannot be made bigger, but a seat that is slightly loose can be made to fit you exactly, and it will be more comfortable than either the smaller seat or the loose one.

Not sure which fixes your problem?Tell us the seat, what is wrong with how it fits, and your height. Sitting too low, sliding about and being pinched at the hips all have different answers and it is worth getting the right one. Call 0115 989 3488 or email Sales@GSMPerformance.co.uk.

All figures read from our own product data across the insert kit and cushion categories, checked 2 August 2026.

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