How do you know when its time to replace your rotors?

Rotors are a very important part of your vehicle's braking system.  There are several things to look out for when inspecting them. As everyone knows the stock rotors for most Lotus Elise and Exige base models are the same rotor for all corners. This means the cross drilling is machined and the vanes are in the wrong direction on one side of the car.

When looking at your rotors the this to look for are:

1. Thickness, minimum thickness for standard brake discs is 24.9mm

• When checking thickness be sure to use a brake rotor micrometer or caliper. They have a point that allows you to check thickness as well as depth of any scoring on the rotor.

     2. Scoring or grooving, some may be normal but as a general rule they should be smooth

     3. Cracking or heat checking. This can happen if you are using your car on the track and are using any heavy braking. Small minor heat checking is normal but should be monitored. If you find any cracks that extend to the outer perimeter of your rotor, that rotor should be replaced.

Exploded View of BAC Mono Body

SRA testimonial - Sector111 Suspension Settings

I got an email from an Atom client, Rich B., who bought an SRA from us earlier this year.  He found the initial springs and settings were too stiff at one of our local tracks, Buttonwillow.  We found the same issues with our SRA so we undertook some suspension testing and development as reported: HERE.

After we completed our work, Rich brought his SRA to us and had us make the same changes to his car.  He recently took it to the track and had the following report:

I just got back from Buttonwillow .... I'm very happy to report that the new spring and damper settings worked great. I ran a full 5 seconds faster than last time; the difference thanks to the springs is HUGE. So much more comfortable pretty much everywhere around the track so I'm not bouncing around under braking, through corners or on the straights and I can hit a couple of berms without any trouble now too. You can also easily see the difference from my on-board videos, the whole car now rides better.   

                                                                             -Rich B.

 The SRA is a fun car that requires your 'A' game while driving at the limit.  I think it is an excellent car for track day enthusiasts and an even better race car, thanks to it's low running costs and reliability.  This simple reminder also proves that tuning a car for specific conditions becomes key to going fast with confidence.

Art Car Parts Listing...plus ReVerie CF Rad Support

Customers have been calling us looking for a comprehensive listing of the parts we have been running on the Art Car.  We've had a great season in Lotus Cup USA this year campaigning our Art Car with Glen Irani.  We've created a separate page on our website listing each of the parts on the car.

We've added the ReVerie radiator bracket to the car.  This required significant modifications including cutting off the stock crash structure.  For this reason alone, we DO NOT recommend it for street use.

Mitch developed new shrouding and ducting for the proRAD.  We ran it at Spring Mountain and then again at Buttonwillow.  Water temps remained low and the new rad position was excellent.  Unfortunately our Dogbox broke which shorten our full test.

We now have a new conventional transmission kit from PB Racing: stronger and shorter gears AND better syncros.  We should be testing this kit shortly.  PB Racing have had excellent results in Lotus Cup Italy with this kit.  They found the kit to be a proper upgrade over stock without the complexities or maintenance headaches of a sequential or Dogbox kit.

Spherical Bearing Conversion for the Lotus

Our MONOball and Nitron Bearing kits have become a popular choice for racers and track enthusiasts who are running sticky tires.  Nitron's upright kit had full spherical bearing conversions and we've been interested in developing a solution to eliminate the balljoint for cars with stock wishbones and uprights.  Mitch has designed our new solution and we've begun testing them.

A full kit will soon be on our Art Car for track testing.  Getting the dimensions correct in this application proved to be a lengthy effort.  We've cycled the suspension in every conditions and configurations that we could brainstorm.  Note the picture below show a stock damper with stock uprights at full lock and compression.  As you can imagine many other configurations needed to be tested as well - which Mitch has patiently executed...This will be a track-use only product.

Mono Build Entry #7

The big news this week is that the Body arrived.  The Mono features full carbon fiber bodywork.  The inner portion is painted black and the top section is typically another color.  Ours has arrived in White Pearl and looks magnificent!

The Mono has real presence thanks to the size of the body.  The body, in person, is larger than it seems from pictures but it still retains a lean athletic 'look'.

We are still working on the chassis assembly before we can move it onto the build fixture.  This week Pat sorted a few items including:

• Steering column
• Wiring harness
• CF storage box install
• Radiator fan mounting

This is a hand built car that requires hand fitting is the classic British manner.  TLC is what we like to call it.  

Mono Build Entry #6

The steering rack has been installed and tweaked to a new spec.  The supplier is Titan, supplier  for our titanQR and raceRACKs.  They also supply the Ariel Atom racks so we've worked with them for years.

The front Bellcranks and sway bar pushrods have been installed.  The Atom has a similar suspension system but lacks the swaybar.  The carbon fiber front storage box was test fitted.  This box is located at the front of the car and is accessed through the bonnet (front hood).  It is a perfect storage area for your helmet.

The rear exhaust bracket and rear sway bar links were bolted to the Hewland trans.  Wishbone brackets were also added.

Various issues have surfaced during assembly that we are recording on a 'punch-list' with BAC.  This list is stored on a shared BAC Dropbox account.  This eases communication for Corrective Actions.  We also continue to refine the assembly manual and have worked closely with BAC to ensure we are building our Monos to the same standard.

We just got word from our shipping company that the body has arrived at Customs in LA.  We should have it this week!

Mono Build Entry #5

We received a large batch of parts from BAC and have taken inventory.  We began assembling again after reviewing our build plan.

The new gas tank was fitted and cover was riveted in place.  Routing the fire extinguisher lines was also done.  This is an option that should be ordered by every track enthusiast.  It is best to install during the initial build as it is much easier to route the lines. Installing it after the car is finished will not be quick nor easy!

We also bolted the hubs to the uprights.  Note the trick green paint marker that confirms the bolt was torqued.  All four of the uprights are the same and also use the same hubs.  This is a welcome design for assembly and service feature.  We need to press in one more bush (which is in the freezer shrinking) into a wishbone and we will be ready to install them.

Suspension Testing: Spec:Race Atom & Lotus Street Nitrons

We tested and conducted suspension development on both the Lotus Elise and Spec:Race Atom last week at Spring Mountain.  We had a new street suspension from Nitron that needed a proper track test and also recruited Dave T. to help dial in the SRA's suspension.  After four days of testing and tweaking, we achieved good results.

Nitron Street Series for Lotus Elise/Exige:

We have been working with Nitron to develop an affordable alternative to a stock Lotus suspension.  Typically most OE shocks are showing wear by 40k miles.  The degradation happens slowly, so most people don't notice that their shocks are worn out.  These Nitrons feature valving that is fixed.  The adjusters shown in this picture will not be on the final parts.  A key feature of these shocks is that they have a threaded body which allow for ride height adjustment and corner balancing.  The stock shocks do not allow any adjustment.

We installed the test set of shocks on a normally aspirated Elise with stock rims and Toyo R888 tires.  We set the ride height to a stockish 135-140mm.  I drove the car on Spring Mountain's 2.2mile config and rode up every bump and curb that I could.  I put 277 track miles on the car and set a fast lap of 1min 58s with dozens of laps under 2min.  A fast time is about 2min on this configuration.  Overall the suspension performed beautifully.  It was compliant and delivered great grip.  Yes, it sways, pitches and squats more than a Nitron NTR series but it is designed as a street shock that may see occasional track use.  We will now place it onto a street car and run through some street testing to confirm that it works properly on the street as well.

Spec:Race Atom Suspension Tuning:
West coast tracks can be quite bumpy and a real challenge for stiffly sprung cars.  Previous track testing that I conducted with our SRA showed that it is very stiffly sprung.  The SRA features double adjustable coil-overs with a bell crank and pushrod suspension.  The car comes stock with 400# front and 500# rear springs.  I spent one weekend at Spring Mtn with the car, comparing it to an Atom3 with the Bilstein adjustable shocks.  The Atom3 was far more compliant through bumps that would fully upset the SRA.  I called the factory and they suggested I test the softer springs they had sent with the car.

I asked our Ride & Handling expert, Dave Thilenius to help us set up the SRA.  We decided to test spring rates on Saturday and then vary rebound and compression on Sunday.  Rebound and compression settings were left alone as we first tested the following rates:

1. Baseline: Front 400# & Rear 500#
2. Front 400# & Rear 300#
3. Front 300# & Rear 400#

Carlos swapped the springs and reset the ride height to stock for each configuration.  The pushrod on the SRA sets ride height - which is much easier than on a Lotus.  We ran 1 warm up lap, 2 hot laps and 1 warm down for each configuration.  We then ran the car on the skid pad in both Clockwise and Counter Clockwise directions.    The SRA comes with Race Technologies data logger, dash and video.  We downloaded the data after each session to see what the data revealed.  Dave also took notes after each session to record his impressions.  Watch the video below to hear some of his comments from one test session.

The skid pad became the test that best determined the balance of the car.  It was clear that the first and third spring config were the best balanced.  The second config. delivered a car that understeered more than the others - the softer spring kept the rear planted!  The skid pad lap times were also the quickest in the third set-up.  Actual lap times were close but we ultimately used Dave's qualitative comments to select the third (Front 300# & Rear 400#) spring config.  This set up managed to soak up the bumps better than the first and delivered a neutral car.  Dave did suggest that the second config. would be the most comfortable to drive for beginners.

On Sunday, we began to vary the Rebound and Compression settings.  The QA1 shocks that come standard on the SRA feature 18 clicks of adjustment for each variable.    Again we downloaded data and recorded comments to evaluate the handling.  We tested ten different settings.  Dave ended up running lap times that were significantly quicker than on Saturday.

I tested the SRA at the end of the day - I couldn't let Dave have all the fun!  I'm at least as fast as the average Atom driver so felt my opinion would be relevant for most.  The car was much better than the original with plenty of grip through the bumps.  It was more compliant but remained stiff.  Unlike with the original set-up, I was able to climb the curbs with confidence.  Ultimately, we landed on settings for the SRA that I think are better suited for bumpier tracks.  Great job Dave and Carlos for wrenching!

The Atom will always be a 'loose' car, especially when compared with other cars - like a Lotus.  The SRA has no wings so remains a car that relies solely on mechanical grip.  The rear bias and power-to-weight ratio make it a car that is even closer to a formula car.  This is not a beginners track car nor one for the faint-of-heart.  Even with our tuning, you need to keep a high level of focus to go quickly. I suspect this is one of the reasons why the Atom delivers excitement in spades...this car is not for wimps!