Lots of people have asked me over the years on how to reduce wind noise in there driving videos - road or track.  While I am not an expert, I have done a lot of experiments over the years to form a view of what works and what does not.  Your own experience may differ and thats good because you can also contribute that on this USA7s forum.  

I am not going to cover which is the best camera or mounting systems in this article – just want to focus on sound. I personally want a good throaty engine/exhaust sound in my videos, nothing annoys me more than seeing a great video with some crap music overlaid. I want to hear that engine roar at revs. If you are like that read on. If you prefer crap music then stop reading now.

Its easy to get decent sound up to about 40mph.  Its after that, you begin to hear increasing wind noise.  

I am not an audio engineer – I just know what I like listening to in a sevens driving video.   I am trying for high quality sound – some of you may agree with me and others may want to short cut.   All of us are right – we deserve to get what we want.

A Se7en has unique acoustical properties:

- They are aerodynamically dirty so lots of wind noise is a given.

- They have a light construction so they transmit more vibration, noise and even electrical interference.

- The light construction can sound “tinny” instead of resonating a nice deep note that a regular car might do with its more enclosed and insulated spaces.

- They have lots and lots of wind noise….did I say that already?

So this is a challenge that even open-wheel race cars don’t really have as most of them have slippery aero bodywork that can hide microphones from the wind, unlike a seven.

Many of the video examples below are illustrating how the sound changes with the different methods. Don’t listen to the whole thing – listen just enough to get a sense of what works or does not work.

So let’s start at a baseline. The GoPro or any numbers of action cameras advertise fantastic sound quality out of the box. That might be so when you are surfing, horse riding, riding a mountain bike, rock climbing or running around with your girlfriend in a meadow.  However that is not true when you stick an action camera on a Se7en and ask it to record a spirited drive or track event.

For example here is an action camera using its internal mic in its regular case perfectly mangling the glorious tones of a beautiful Cosworth Duratec engine in this gorgeous Caterham:

Hmmm…. So that does not work. 

Lesson 1 – Position the microphone out of the wind.

So let’s try and use an external microphone and see if that improves matters? Just a simple Olympus ME-52W connected to a POV VIO HD camera with the mic under the canvas tonneau in the boot area:

Not great.  One of two things is happening, (a) the level of noise is over-powering the ability of the mic to process the sound, and/or (b) the mic is over-powering the ability of the camera to process and record the intense noise frequencies.

So with exactly the same mic mounted in exactly the same position let’s try it with a Go Pro HD2:

That’s better. Still a little soft in volume and too much wind.

Lesson 2 – Some cameras are better than others at processing recorded sound.

Somewhere around this point in my discovery process, I read lots of tech articles about how you need a powered microphone to improve dynamic range, improve gain and improve recorded audio quality.    So I graduated to an Audio Technica AT-3350 lavalier omnidirectional microphone. This has a little battery within it. So let’s mount it to a GoPro and locate the mic under the rear tonneau in the boot area.

Much better. Much more differential noise than I would like.   Still some wind noise.  Not as throaty as the engine sounds in real life – a little thin sounding.   Still not a great recorded representation of the sound we hear from our cars.

Lesson 3 – Power is better than no power when using a microphone

So now I am thinking I need to move the mic around to find a better position within the car. Positions tried and discarded:

• Under the passenger and driver’s seat – too much wind noise
• Under the dash on the center tunnel – too much wind noise. I guess air flow rolls off the dash and circles under the dash and foot well area?
• On the rear wing in front of the exhaust tip – way way way too much wind noise even with a 'dead cat' cover, also known as a 'dead kitten' cover. A 'dead cat' cover is a furry item that covers the entire mic recording element and is intended to protect the mic from hearing the wind.  Example linked: https://www.amazon.com/dp/B07RKT7LLH/ref=cm_sw_em_r_mt_dp_98M5VD26QPTMR1QR2M5Q
• Mount the lavalier mic to the exhaust tip using painters tape.   Don't repeat my mistake - I burned the tape, melted the mic, recorded nothing worthwhile and I felt like a right muppet.

After hanging upside down in my passenger footwell, I saw a nice ledge way way up under the passenger side dash where the relays are located. So I gave that a go.

I also upgraded mics to a borrowed demo model of an Audio Technica AT689. This is an expensive powered mic (now superseded). I do not recommend trying this at home.

Much better. No wind noise now but because it is next to electrical components and it is unshielded you get static and interference. You also can hear the cycling of the fuel pump relay if you listen carefully. So that is another fail.

Lesson 4 – Sticking your mic next to electrical components in a car will likely get some static/interference noise

I do learn that a better quality microphone will produce better sound recording results – you get what you pay for. From my phone discussions with the GoPro tech people on how they produce their videos I learn that they frequently use a Sennheiser MKE400 or in one case a Rode Video Mic. Both are priced in the $200 range. They also sheepishly admitted they from time-to-time use separate digital sound recorders to blend sound into the sound recorded by the camera on a post-production basis. More of digital recorders later.

Lesson 5 – With microphones you get what you pay for

So let’s try the same mics and locations in different cars of different USA7s members to see if I can replicate the results consistently.   Using Jeff's @JBH Caterham, I set up a test with an AT-3350 mounted in the boot area under the tonneau using a GoPro HD2:

Without showing you the failed attempts, I eventually succeeded.  Experiment replicated.  

Consistency is a challenge. I installed all of these mics using the same technique I tried on my car and I do get failures at an unacceptable rate. 

Some issues driving the problems are:

• Car vibrations making the mic to camera and internal mic connections break.
• Flat battery in the AT-3350 (no idea how long the battery lasts – I seem to get 1.5 days continuous track time from my testing but it always seems to go flat precisely when I really want to rely on it!
• Forgetting to turn the on switch on the AT3350 (no excuse – shoot me!)
• Vibrations eventually killing the mic so that it no longer records (internal fault to the case or some break in the mic wire?). Been through 3 mics this way.

It is very difficult to work out at a track or during a drive whether you are recording good sound or not. There is no effective way to test this out in the field. Easily done on a laptop though but who wants to do that in the middle of a drive?

Keeping it simple is important as you have a lot to remember to coordinate when you are about to go on track (helmet, gloves, belts, camera, fuel, mic turned on, bonnet clipped down, etc.).  A Sunday blat is easier but you still want to get out and drive rather than faff around with a microphone.

Lesson 6 – This learning process can be frustrating!

So now I try for the Holy Grail. I give up on the cheap but fragile AT3350 and I run the AT689 mic forward to the engine bay and again using 3M painters tape, tape it to the shelf above the passenger foot well. The metal in theory should shield the mic from electrical interference and I should get lovely throaty sound from the roller barrel throttle bodies. Recorded with a GoPro

And so it works. On back off I do get a tinny (another technical term of my making) sound as the intake is closed off but the rest of the sound is perfect. I even hear the CR500 tires being tortured through the corners.

Lesson 7 – Engine bay on the intake side can produce really good sound with an external mic.

So now can I replicate the sound using different mics same location? GoPro HD2 paired with an Audio Technica AT Pro-CM24 shotgun mic.  You are riding aboard with Mike @Kitcat in his Caterham.

Success!!!    The AT Pro CM24 was mounted drivers side above the pedal box on the Caterham.

As a contrast here is an Opteka VM2000 shotgun mic taped to the inner scuttle above drivers knee – not bad but a bit rattly and more wind noise than I would like. Would prefer just engine noise/exhaust noise.

Lesson 8 – Engine bays are a good location for microphones as wind noise is largely minimized and intake sound is pretty good

So now my question is does it work with other cameras?   Yes – tested the AT689 with the Drift HD Ghost and the Braun Six Zero with mic mounted up under the bonnet above the passenger foot well.

Braun Six Zero Camera and an AT 689 mic

Drift HD Ghost and an AT 689 mic

The Drift camera is not quite as good as processing sound as the Go Pro or other cameras with an external microphone. It picks up the deeper intake notes but seems to have trouble with the higher pitch notes once the intake is closed. Seems like Lesson 2 holds true.

Lesson 9 - Some level of testing is required to make sure these solutions work on your seven. There is no out of the box solution for a seven

So then I tried separate digital recorders, both mounted in the cockpit using the screw clamp mount. The first tried was a Tascam DR05 and the second was a Zoom H1. Most professional videos will use a separate recording source rather than use a mic attached to an action camera. This makes sense when you think about it as a digital recorder of sound is a complex piece of equipment, larger than the action cameras we are using. So its dynamic range, sensitivity of mic, noise reduction, and general ability to record a good track is always going to be better than the compromised equipment contained within a tiny GoPro box or the like.

The one major downside with these is you have to spend time post production synchronizing video with sound (either with the regular video editing package or an application like Race Render. When you start recording you would clap to get a visual and aural cues from which to base the synchronization

However, I found the vibrations from the car killed both the Tascam and then the Zoom H1. They would turn themselves off or just not record. So they were returned for refunds.

Lesson 10 – Digital recorders offer the promise of better sound recording but more stuff to fuss with recording and sync with video later. Better to keep it simple

What sounds good to me does not sound good to others.   I prefer a little more bass in my sound mix. Others may prefer a little more treble when they hear their car recorded using my equipment.

Lesson 11 – Sound is a personal thing. You may not like what I like – so experiment.

This is my view on getting decent video sound on a Seven drive or track day. I don’t profess to know all the answers so please constructively contribute with details and examples of what you think works well for mic position/location and equipment used.

Lesson 12 - If you want to go to the next level then listen to some better experts in this field

I have continued my personal interest in this topic by following up with WindCutter who specialize in sound recording solutions including wind shielding for microphones. Below is an extract from an email exchange I had with Michael Stamp of WindCutter. He very kindly consented to me posting extracts of his email on this forum as I believe it is very helpful for us to hear from a professional.  Indented text in blue is from Michael's email:

A link to Rob Nokes Guide to Recording Cars is here:

Rob Nokes Special: Guide to Recording Cars (designingsound.org)

I will note that I use the WindCutter microphone "dead cat" wind shielders and they have been the most durable out of all brands I have used so far, although I suspect they would melt if taped to the exhaust...

Lesson 13 - Keep trying!

Continuing in my journey of quality audio on Caterham track videos, I have reached 'nerdvana'

Garmin VIRB action camera mounted to rollbar using a Manfrotto clamp. Twin mic set up using a 3.5mm cable splitter. Twin AT Pro CM 24 mics - internal battery power works better than camera providing power to mic. Both mics are covered with 'dead kitten' mic covers.

One mic runs forward along passenger side of cockpit and around outside of scuttle into engine bay where I tape down the mic with non-marking painters tape under the intake on the top of the passenger footwell inside engine bay. Photo link shows the line of blue tape and camera on roll bar.

Second mic runs backward and is taped down next to rear exhaust - photo illustrates. The blue painters tape shows the line of wire between camera and mic.

End result is pretty good.

If you have a side exit exhaust then revert to single mic setup with mic in engine bay or second mic inside boot (under boot cover) near side exhaust.

Conclusion 

I hope your efforts end up as satisfying as I am with my end results.   Look forward to seeing you post your backroad blat and track day videos on this forum.

Most people just use the GoPro roll bar mount to attach their camera to their se7en and then drive off.  However, you will quickly discover that our little cars are fairly high in vibration despite generally having a compliant suspension and good ride.  As a result, a peculiar effect can be generated on video called "rolling shutter."

Rolling Shutter Effect

Borrowing from Wikipedia:

Rolling shutter is a method of image capture in which a still picture (in a still camera) or each frame of a video (in a video camera) is captured not by taking a snapshot of the entire scene at a single instant in time but rather by scanning across the scene rapidly, either vertically or horizontally. In other words, not all parts of the image of the scene are recorded at exactly the same instant. (Though, during playback, the entire image of the scene is displayed at once, as if it represents a single instant in time.) This produces predictable distortions of fast-moving objects or rapid flashes of light.    This is in contrast with "global shutter" in which the entire frame is captured at the same instant.

To illustrate, here is a side by side comparison.  Left half of a screen is with a CMOS chipset video recorder producing rolling shutter or "jello" effect. The right hand side of the screen is with a video camera with a CCD chipset with a global shutter set up.

Clearly the left hand side of the screen wobbles around far more than the right which is steadier and far more enjoyable to watch.  

An illustration of the rolling shutter effect in this Caterham video - its particularly pronounced at idle when the car vibrations sync with the shutter timing of the video.

So what can be done to avoid it?

A couple of things:

• Buy an action camera that uses a CCD chipset (instead of CMOS chip as in a GoPro for example) as these are predominately using global shutter
• Buy a good roll bar clamp
• Use a camera with an active steady shot feature

Buy a Camera that Uses a Global Shutter

Dealing with each in turn.  It is not automatically guaranteed that a CCD chip in an action camera will use global shutter to record video.  In fact it is possible that a CCD chip may still utilize rolling shutter.  Further, it is extremely rare that you will be able to find an action camera that does not use rolling shutter.  More expensive professional cameras will likely use global shutter but these are $1000+ and well beyond the budget of us amateurs.  

Buy a Good Roll Bar Clamp

The standard clamps provided with your new action camera are unlikely to cut it.  Lots of testing over years has led me to use Manfrotto Super Clamps.  They are expensive, heavy but work very well.  They are strong and stand up to enormous abuse without failing.  

The standard clamp looks like this:

There are other versions of this clamp with different shape locking mechanisms and if you look closely on Amazon you will find similar unbranded copies for cheaper money.  

That brass stud is important as it installs into the clamp and you then screw your camera onto it.  

There are also Nano clamps - smaller versions which are excellent for installing cameras on wishbones or headlight brackets for a different video experience.  

Out of side in this photo is the screw hole on the end of the clamp that will take a brass stud to allow you to screw your camera on.

Sometimes, these clamps, once mounted in place, will be positioned so that the camera cannot be aimed correctly.  In that instance you will find a ball head to be helpful.  These come in a variety of sizes and prices but allow infinite adjustability in aiming your camera exactly where you want it and locking it tight so it will not move.  

Sometimes the ball head mount will not get your camera in just the right position.  In that case, ball socket arms will provide the needed extension.  I find the Ram Mount brand to have a good selection of options.

RAM Mounts - Mobile Mounting Solutions

Use a Camera with Active Steady Shot Feature or Use a Multi-axis Motorized Gimbal Attachment

Many higher end action cameras will offer a form of image stabilization feature that reduces vibration effects from rolling shutter. This is a software driven mechanism to stabilize the image being recorded. 

The physical version of this is a motorized multi-axis gimbals, frequently seen in drone photography which uses physical movements of the gimbal to offset the physical movements of the camera.  

However, not all have the same effect in the end result.   Action camera gimbals are designed for relatively slow movements and not high G forces of a vigorous backroad blat or a track day drive, as seen in the following example video.

So the multi-axis gimbal is a fail for us amateurs unless you go high end which is thousands of dollars.  

So that leaves us with the software version that is built into the cameras.  This technology has improved drammatically in recent years.  Five years ago I tested a Sony action camera and found the so-called "SteadyShot" feature to be terrible - moving its aim around all over the place.  

Now, the current crop of GoPros, DJI Osmo Actions, Sony Action Cams, etc have very sophisticated software to reduce vibrations, producing a particularly professional image.  When you select this feature you should know that it works by allowing the recorded image counter the movements from vibrations around an image center spot.  It then crops the borders of the video so you never see the countering effect that is going on producing the effect of a closer video image.  Each camera manufacturer calls this image stabilization feature by their own marketing term.  Sony uses SteadyShot, DJI Osmo uses RockSteady, and so on.

This is best seen in a back to back comparison.  Same car, same driver, same camera, same circuit, same day, same Manfrotto mounting clamp and ball head.  The difference between the two is Video 1 has no image stabilization.  Video 2 has the image stabilization turned on.  

Video 1 - No Image stabilization

Video 2 - Image stabilization turned on

First thing you will notice is that the view of the cockpit and my body is cut off compared with Video 1.  To my mind, Video 2 has a smoother image.  Dashboard label letters are nicely crisp.  Momo on steering wheel is nicely defined.   A little less image vibration in Video 2.  You should make up your own mind when thinking about buying a camera for this feature.  

So Where Do You Mount the Camera?

You have a range of options.  Think big.  The traditional view is on the roll bar above the driver - like the ones immediately above.  But keep in mind that height above the asphalt tends to slow the sensation of speed.  

With that in mind, you should consider alternatives:

(a) Hang it off the side.  Roll bars have upright pieces.  The clamps shown earlier work well to mount on the side of the roll bars.  Aim it over the driver's shoulder or maybe the passenger if you are out there terrifying them with your driving prowess (or lack of?).

(b) Point the camera backwards - If you are anything like me, you will be pointing people by.  Or if you are on a road tour with some se7ening friends then you get to focus on them following you.  Or maybe, just maybe, you will get lucky and see someone goof up while following you.  This produces a video like the following:

Oops!

(c) Front wishbones - This is a good location to get the sensation of speed and movement.  Remember that it is subject to a lot of movement in the front suspension and a level of undampened asphalt vibrations.

(d) Headlight stays - These are a great location for 360 cameras.  You can clamp to the metal stay then I use additional painters tape to provide additional support for an extension arm to the camera to steady it.  

If you have never used a 360 camera before, play the video and while playing use your mouse or track pad cursor to click and drag the video around - left, right, up, down.  You can face the video back at the driver or possibly study the track map that GoPro/Garmin/Sony/etc can overlay on the video.  Track cars around as they are being passed.  The big downside of these 360 cameras, apart from cost and massive video files, is that they generally do not have an external mic capability.  So wind noise will be a factor you have to deal with.  

Wrap Up

You may never remove all the vibration effects present in your se7en videos but hopefully this will give you some ideas to significantly improve the quality of your se7en videos to show off to your family and friends.  

Getting comfortable in your Se7en is essential to stay firmly located when driving vigorously - backroad blat, autocross or track day.  This means you have to have a good seat.  The standard offerings from Caterham, Birkin and Westfield fit the majority of the population well.  However, they may not fit some drivers or be suitable to track days or autocross.  Taller drivers may want to gain some leg/steering wheel clearance or get lower in the car by 1-1.5 inches to allow better roll bar clearance for their head.  

A resin bead seat may a solution for the needs for those drivers who need additional room or locational anchoring.  This article is to take you through the basics of of making a resin bead seat for your car.

Types of Seat Kits

There are a couple of seat making options that you will come across:

1) Seat kits

2) Seat insert kits

A seat kit is going to replace a seat.  A seat insert is intended to fit within an existing seat like the photo below:

If you need to replace the whole seat - base and backrest then a full seat kit is going to be what you need.  If you wish to keep the existing backrest but replace the seat squab/base with a foam or resin seat then a seat insert kit is going to to be sized better for your purposes.  The process described below is essentially the same for both seat and seat insert options.

Then you will want to consider the different options of seat material available in kit form:

1) Bead resin seat

2) Two Part Foam

3) Expanding Foam

Both have merits depending who you listen to:  

• The bead resin seat is using similar shock absorption material to what you would find inside a motorcycle helmet.  Proponents claim that it has superior safety in an accident than the foam, having been tested by IndyCar and F1.  
• The foam seat proponents claim it is a better system as some kits achieve SFI 45.2 qualification
• The expanding foam proponents talk about how much easier and quicker is to produce a result than the other two

I am not going to provide an answer to what is better.  Various racing forums have debated this at length and never achieved a conclusive outcome.  One thing I will note is that any seat subject to an impact should not be used again - its similar to helmet safety in this respect.

Seat Kits Available for Purchase

Some of the better known kit options available for purchase are below:

Bead Seat

Creafoam Bead Seat Kit - Pegasus Auto Racing Supplies

Bald SPot SPorts Creafoam Bead Seat Kit - DIY Creaform Race Seats (discoveryparts.com)

Bald Spot Sports | Providers of Performance Enhancing Foam Solutions

Profi Seat - schroth.com | SCHROTH Safety Products

Custom made racecar seating by ButlerBuilt – Bead foam insert kits. BUTLERBUILT Racing Seats & Motorsports Safety Equipment

Foam Seat

Pour-in-place urethane kits by ButlerBuilt – E-Z Sert | Race car seats. BUTLERBUILT Racing Seats & Motorsports Safety Equipment

Expanding Foam

Custom Seat Kits - Motorsports Southwest Motorsports Southwest (motorsports-sw.com)

You do not even need to buy a kit.  @yellowss7 made a seat base for his Caterham by buying foam bean bag beads, a space saver vacuum bag and a two part epoxy mix following a similar process to what I did below, before covering it in Nomex fabric. Amazon is your friend for these pieces.  

Making a Resin Bead Seat

For the purposes of the remainder of this article, I will be using the Creaform Bead Seat Kit from Bald Spot Racing (also available for purchase from Discovery Parts and Pegasus).  I purchased my kit from Pegasus Racing.

 Creafoam Bead Seat Kit - Pegasus Auto Racing Supplies

Before starting I recommend watching the instruction video.  
 

I recommend you have a friend to assist you in this, especially since you may be stuck in your Se7en while the seat cures.

My first lesson - the XL size of the Creaform seat kit is too big for the bathtub area of a Caterham SV even after removing everything in the seating cavity. Hindsight says it should have been a Large or possibly a Medium sized kit.  My second hint for you is wear the clothes you expect to be wearing when you are driving.  If this is a track car or autocross then maybe you wear race overalls?  Your clothing for this fitting will memorialize your shape in the seat so you want a close approximation of what you intend to be wearing when you are driving.

Step 1 is vacuum out all the gravel and debris from various drives.

Step 2 is tape or cardboard over all the sharp protrusions in the space that would otherwise threaten to rip the plastic bag of beads and cause them to flow everywhere in the cockpit. So bolts, chassis tube ends/braces, belt buckles, etc

Step 3 is trial fit of bead bag (no resin yet).  You GENTLY sit in the car on top of the dry bead bag.  This test showed pretty quickly that we had too many beads in the bag. So about 25% to 35% came out and we test fit again. That was a much better fit.  

Step 4 is prepare for the vacuum - there is a hose into the bag. You connect it to a vacuum and it keeps the bag under suction through the initial cure fitting.  Some people talk about buying a cheap water valve to go between vacuum and hose so you can turn vacuum cleaner off but I doubt you can keep enough vacuum on it this way.

Step 5 - at this point, take a bathroom break, cigarette break or whatever you need as you wont be going for a while.  Secondly, wear long pants as the resin curing is quite hot on bare skin.

Step 6 - mix the resin into the bag. We ended up using all the resin as the mixture felt too dry. You put the bag on the floor and gently knead the resin around the beads so there are no clumps, taking care not to break the bag.

Step 7 - Bag with beads and resin into the car. Then lower yourself GENTLY into the bag. Squish yourself, butt, legs, shoulders, hips, etc. to get comfortable for a good driving position. Move the beads around to where they need to be. Once you are comfortable then stop moving and sit still. Vacuum is on.   Your assistant can bring you a beer and you both take a break from while the seat cures.  Maybe gaze around the garage, or in my case the TK Autosports hangar.  

At this point you contemplate the messiness of our existence. Jeff's @JBH blue Caterham awaiting yet another rebuilt engine (hint - don't use 10,000rpm on a Zetec). A certain blue Holden awaiting its rebuilt engine to go back in. A Corvette with a blown clutch. The already trashed rental blue Datsun 200SX for hackers to destroy further. The number 51 Mazda RX7 in for yet another new engine.  

Step 8 - Escaping from your "mould."     After an hour I was allowed out.  Less resin would have seen me escape at the 30 minute mark but the seat felt too "squishy" at the 30 minute mark so for caution I stayed there for the full hour for the seat to firm up more.  At the time of my exit from the seat, the seat had firmed up enough that my butt impression was not going to move. Getting out was entertaining. I could not use my traditional hand holds to lever myself up plus I could not move my legs much given the beads. And my non-removable steering wheel was where I needed to be. Having your buddy assisting, collapse in giggles at your difficulties was never going to help me but eventually...

Yes folks, that impact crater, is my butt impression.    Its amazing where your body leaves divots - a love handle on one side, my leather belt line, a wrinkle in my shirt, a hole where I had my SUV keys in my pocket, etc., you get the idea.   At this point we turned the vac off and left it to cure over the holidays.   It only really needed 24 hours but we were heading out on holidays so not a problem.

Step 9 - Removing the seat from the car to shape it.  The seat has now hardened up fully.  Using a hot knife you trim away the excess pieces of bead/foam so that it will come out of the car easily for further shaping and covering.   It was at this point I discovered something critical:

• If the bag is too big then it bunches up and creates chasms of plastic in between the beads.  The XL kit was too big a size for a Caterham SV - learn from my lesson
• If you mold a bead seat under the lip of the center tunnel then it will not like coming out.

The hot knife is key. It makes life so much easier carving and shaping the seat for the space. You need to car space channels for the belts on the sides and underneath for the submarine belts. Need to carve a hole for the submarine belt to surface through the seat to meet crotch.  A hot knife looks like this:

Because of my errors, I cut my seat out of the car in two pieces which made it far easier to manage than one who seat.  It was then trimmed neatly.

Step 10 - Covering Your Seat

While you can leave your seat in its exposed bead foam state, you will be abrading beads everywhere and it will be messy.  A seat covering is recommended.  You have a range of options to cover your seat - duct tape, nomex fabric, etc.    I chose Nomex fabric and had the upholsterer do it in loose style so I can remove it for cleaning in case of any accidents.

Step 11 - You need a head rest.  By removing the original seat with integrated head rest, your head is now exposed to impacts against the roll bar.  You have a couple of options:

1) Use roll bar padding like that in the photo:

2) Fabricate a head rest

3) If you have a Caterham then you can buy the kit that just bolts onto the roll bar.  I upgraded the foam that came with the kit for some thicker "NASA" foam. 

End Result

I am very happy with the end result and are now able to sustain higher G forces on track without fatiguing and find it much more comfortable on my back and neck.  I am lower in the car which has reduced the level of wind buffeting I get.  Hope your results turn out as well as mine.