Pro-Seat Insert Fabrication for Sportscars

Alex Powell from Pro-Seat in the UK has been with us for the last two weeks training us in the art of producing custom seat inserts for sportscars.  These inserts are designed to hold the driver properly in his/her seat, so that they do not move while driving under load.  This has been a challenge for me in almost every car I've put on track.  I'm constantly fighting g-forces and sliding around in my seat.

Note the F1 driver on the screen?  

Alex's father, Trevor, invented this FIA-approved bead-based seat insert in 1992.  I met these two gents back in March through our partnership with BAC.  Pro-Seat have supplied all levels of motorsport including F1, CART, WRC, LMP and much much more.  Many famous racers have been well fitted and protected by a Pro-Seat insert.

Alex began our lesson by showing us the process of 'dry-fitting' a seat.  This is done with the bag of polystyrene beads by approximating the amount of material required by the driver.  A vacuum is pulled on the bag, the insert is installed and the driver put in place.  We used an Atom3 in this example - I've been tired of being thrown around in the stock Atom seat!

With the driver in place, the beads are sculpted around the body and fill in any gaps between the body and the seat.  Driver seat height is checked to ensure he/she is sitting high or low enough.  To be clear, the Pro-Seat insert does need a 'shell' to be molded into to provide it structure.  It is not a stand alone seat.  We use the Atom3 stock seat as our 'shell' for this insert.

 The driver is carefully extracted from the insert and a rough insert remains.  See it below.  This is used as a reference to determine where the beads need to be placed on the final insert formation.

 Trevor is shown below, pouring a two-part resin into the bead bag.  This resin is a glue that holds the beads together and allows them to form to the drivers body and maintain its shape.

When the resin is added, you have approximately 3 hours to form the final insert.  The beads take on a doughy consistency so it becomes quite easy to form and shape.  The 3 hour window gives the insert maker, enough time to sculpt his masterpiece.The rough insert still has the plastic covering that will be trimmed off along with the excess polystrene beads. This rough insert still needs to cure for 12 hours before we can begin our trimming process.

The next stage of the insert construction will remove the excess parts.  First rough cuts are made and then finer and finer shaping cuts are used to create the insert.  Holes are cut out for waist and anti-sub belts.  The insert is then sanded to give a smooth surface for the fire-retardant upholstery.  

The final insert is shown below in an Atom3.  These inserts are seat and driver specific - unless of course you have an identical twin.  An interesting characteristic of the beads used in this insert, is their ability to sustain some deformation yet still recover its original shape.  Pro-Seat often cite the example of Mark Blundell crashing his Indy car in 1997 at Homestead Spring testing.  This crash destroyed his car but the insert was still useable for the remainder of the season.  Not that I plan to experience this benefit, but I am sure glad that the insert offers that level of protection.

Though this insert is a natural product for formula style cars, like the Atom or BAC Mono, it can also be used in traditional race seats.  We produced one for a gentleman with a Recaro ProRacer HANS seat as shown.  See the inserts below.

Recaro ProRacer

Insert for Recaro ProRacer

John races his BMW 3series in SCCA and has found the seat to be uncomfortable as he has some hip pain from a previous accident.  We removed the seat padding and fit him with an insert.  We think that even clients with traditional race seats can benefit from a Pro-Seat insert.  So expect to hear about us offering this product and service for all sportscars in the very near future.

Laguna Seca: Ariel vs. Lotus

One question I am often asked is what is quicker on the track a Lotus or an Ariel? We spent 3 days at Laguna Seca (LS) this past weekend to help answer this ever-burning question. We put our Atom3 & Elise to the test this weekend by comparing my own laps and by reviewing the actual times put down by the fastest Ariel & Lotus drivers. Luckily for us, both the West Coast (Atom) Adventure and the Lotus Challenge Series were both being held at LS.

We brought up our Elise which was now sporting several new upgrades including: Nitron 46mm shocks, Wider forged wheels from SJ, Race Diffuser & Side Sills from IMRP, A6 Hoosiers, & a new BOE muffler that was designed to meet the strict noise requirements at LS. We also continued acquiring data on our gPAN and transCOOLER products.
Our new Atom3 was also getting wrung out with new SJ forged wheels shod with Hoosiers A6s. The fronts were 205s and the rear were 245s. We had to remove the fenders to clear the rear tires. The stock muffler remained on the Atom3 to insure we did not suffer any noise problems. We had moved the brake pedal pad over to the left to add some clearance with the accelerator - it was noticeable improvement for me.

I spent the first 1.5days running the Atom. Frankly it took me at least half that time adjusting to the quickness of this machine. Even though I had tracked my Atom2, this car required new changes to my driving style. The shifter is very close, almost too close. I required a serious recalibration as a result. I ran the stock sized Yoko A048s initially, then switched to the A6s and saw my times dropped 2 seconds. The grip was awesome and put a real strain on my neck muscles. I had a passenger during my fast lap so am sure that I could run a quicker time solo. The A6s were a strong recommendation of my friend Darin - who is a very talented Atom driver (more about him later). The oversteer that I felt at corner exit with the A048s was almost completely eliminated with the A6s. Larger tires on the rear of this car clearly helps. The Atom should not be a track newbies first car. It responds much faster than other street cars and requires your full attention at all times. Ultimately I ran a 1min46s lap.

Project Nirvana has come a long way since we first bought her a year ago. In fact, LS was the first track that we had run our Elise at. It was cool to come back with Nirvana in it's current state of tune which included our Katana2 (CARB-pending). We ran her initially with R888s on Monolites and then switched to the wider SJs with the A6s. The SJ wheels are 16x8 in front and 17x8.5 in the rear. Clearance was a concern so we took things carefully. We chose to run conservative ride heights (120mm & 125mm) and added additional camber at the track (2.6deg & 3deg). The added aero was newly installed and were proven parts run by many LCS racers. She looked super aggressive and utterly bitchin' with these new upgrades. Nirvana was pure driving bliss. I was very happy with her performance and made some adjustments to the new Nitrons. Unfortunately our sessions were quite short on Sunday so I did not get to optimize the settings. Regardless my best time was 1min47s. I'm sure I could drop these times given more laps.

So clearly I was able to run faster in the Atom than the Elise. I think superior acceleration of the Atom shines on a track like LS with its big straights. But the lack of downforce and quick reaction made it a handful for my modest skills. It delivered a rush that is incomparable. The Elise on the other hand was a much more 'relaxed' car to drive. It reacted much slower than the Atom and did not punish my sometimes ham-fisted moves. My confidence level was clearly higher in the Elise as a result. Interestingly enough, I believe the Atom made me a better Lotus driver. So the Atom wins the 'faster-lap-with-the-same-driver' contest.

Comparing the fastest times posted by Atom & Lotus drivers revealed a similar result. The quickest Atom was driven by my friend Darin who posted a 1min33s time with his NA 245hp Atom2. He posted his video as proof: DP workin' LS. See his aggressive line through the corkscrew pictured here. Another friend, Andy K. cranked out the fastest times in his Lotus 211 with a 1min36s lap. Clearly both cars can be driven at paces that are downright scary fast but the Atom seems to be the faster car. Another interesting fact is that the Atom can be driven on the street while the 211 is track-only.

Do the faster laps make the Atom the better of the two? No, the Atom works better for the driver who wants to feel everything NOW and capable of dealing with it! That makes it better for some but not all. The Lotus is more gentleman-like in its response and easier to drive fast. Both are lightweight cars that deliver driving enjoyment beyond the typical sportscar. I guess I should pinch myself now as I get to drive both...