1.5 laps at Autoclub Speedway in the FR-S

Not the fastest lap of the day. And you can tell how slow the car is in a straightline. It takes a while for the traffic to start to pass me, but when they go by in a straight line you can tell the hp differential.

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Brake Test Track Feedback

I’m sitting on a worn pleather seat at 10,000ft above sea level.  I’m loosing the battle for the armrest. I’ve spent way more time in this uncomfortable seat than I care to think about in the last couple weeks since I installed the Essex brake kit on the FR-S.  I’ve gotten a lot of emails and PM’s asking for track feedback.  I need to edit the video of the day at Autoclub Speedway in Fontana.  The best footage I have was unfortunately interrupted by the now infamous McLaren loosing a fight with a cement retaining wall.  This is basically a really elaborate excuse for a blog post without a ton of pictures and video to back it up.

In previous posts, I suggested that the biggest advantage of the Essex brake kit was the 20lbs it sheds.  And this is indeed a big advantage.  I changed over to these brakes before I tested the limits of the stock system.  But I have watched others on track with me or that post online, and it has become pretty clear that the stock braking system can not handle a lot of track duty.  Rotors show significant ware after a couple days (I know of 2 that have cracked on the 5th and 6th track days).  And pads aren’t lasting that long.  A set of XP10 Carbotechs lasted a friend 3 track days.  I would expect that on a heavy car, but this surprised me here.  The cost of consumables in the brake system is higher than I anticipated on this car.  If you decide to keep the stock brakes for a while and you visit the track frequently, you need to set up a duct system to try and see if you can get some more life out of the stock parts.

My initial impressions of the Essex brakes are as follows:

You can feel the loss of 20lbs of unsprung weight. Turn in is a bit more crisp, and steering feedback is improved.  This is important for me as the addition of 255s did make the steering a bit more numb than stock.  The stock liveliness has now returned, but now with monster grip.  The stock pedal felt great before you got a lot heat into the system.  But as temps went up, a numbness crept in that while the brakes were effective, it was hard to tell when ABS was engaging and when you were simply at the threshold.  Earlier I suggested this was tread squirm on the Hankook RS3’s.  This was only partially true.  The Essex brakes allow for the same great pedal feel and articulation of the cool stock brakes to be carried deeper into the on track session.  The tires do overheat and don’t like to communicate under threshold braking like a proper race tire does.  But the larger system retains pedal feel that was lost in the OEM configuration.  I look forward to trying a treaded R comp tire to fully understand what is tire feedback and what is brake system sensitivity.   I suspect the Essex kit will further distance itself from the stock system with proper rubber.  While I did not have heat paint on rotors or stickers on the calipers, it is pretty evident that these brakes stay cooler than the stock units which will lead to extended life of parts.

Brake bias is similar to stock.  I am running AP C300 pads in the front (Essex recommended) and Carbotech XP8 in the rear (not Essex recommended). Essex recommends a balanced approach to pads running the same front and rear.  The hot setup on miatas is different than that, and its what I tried.  I think I could fine tune the system with a pad change, but here are my current observations.  There is more front bias than when I was running stock fronts with Carbotech XP10s.  For street driving or novice track driving, this is a fine combo.  There is a hair more front bias with the current pad set up than I prefer in a race car in the dry.  But I suspect in the rain, this is just how I would have things adjusted.  I believe I will swap the rear pads to something with a higher coefficient of friction in the near future.  I like a car that will rotate quickly under trail braking, and I don’t mind if it is a little twitchy making transitions on different types of pavement while threshold braking.  You aren’t likely to spin a FR-S with this kit and pad set up under braking.  The way the car is setup now is easy to drive, it just might not be extracting all of the potential out of the system as the rear brakes aren’t doing as much work as they could.

A pleasant bonus for this upgrade is how it interacts with the ABS system.  The stock ABS system in the FR-S rivals that of the S2000, which in my opinion is one of the best systems available in reasonably priced sports cars.  And the Essex caliper and piston choices I think have improved upon it.  With a little practice, you can feel the ABS engagement point, and it is easy to modulate in and out of its use which when the OEM units got hot became difficult to do.  ABS engagement doesn’t upset the car and its not so violent that it interrupts your concentration.

The only thing that caught me a little unprepared is the wrench required to bleed your fluid.  The recess in which the bleeder sits has ridges around it that require a very thin crescent wrench.  A standard one won’t allow you to effectively open and close the nipple.  If this however is the biggest issue I can find with the brake kit, this is going to be a success.  $2500 for 20 lbs of unsprung weight falls into the “bargain” category when it comes to performance weight loss. Now if someone would only offer a 2 piece rotor for the rear.

So in current configuration, at Autoclub Speedway’s oval, the car turned 2:01’s in the morning session.  Its probably a sub 2 minute car when you tighten the nut behind the wheel a little.  Considering the car can be driven with the gas pedal all the way on the floor through the banking and the car never goes more than 122mi/hr, that is pretty quick.  It could use a little more power.  I’ve got a short video ready to upload once I get to a larger bandwidth connection.

New Front Brakes

It’s been too long since my last update.  I think I have sensationalized being “first” to do things in a new chassis.  The reality is being first is frustrating.  Being first shockingly means no one has done it before. I know it’s obvious when I say it like that, but it wasn’t so obvious when I was thinking about how cool it is to be “first”.  It also means there are very few companies out there that can actually help you accomplish what ever it is you are trying to accomplish “first”.  I haven’t posted much as unless you are doing something completely custom, there isn’t a ton available for these cars that I think is of a high quality that improves the overall performance package.

In my last post, I put up a baseline dyno.  I’ve since added a Berk midpipe, but for a myriad of reasons, I haven’t gotten the updated dyno, but I will.  This update will focuses on what you should be working on before you add power anyway – brakes.

What was hidden under all the packing peanuts: Rotors, 2 sets of pads, calipers, brake lines, and brackets.

Essex Parts is in NASCAR country.  Based in North Carolina, they supply equipment to pro teams and grassroots ones alike.  They have developed 2 front axle brake systems for the FT86 of varying sizes leveraging the AP Racing parts bin.

rotor size is almost identical

Their Endurance kit is a significantly larger J hook rotor that requires a 18” wheel.  While the mammoth rotor looks cool, I have yet to see a FR-S in development that needs this much heat dissipation. The smaller of the two kits is the Sprint system.  Its rotor is only 11.75” in diameter – only a hair bigger than stock.

The difference in vane size and rotor width is obvious. Bigger vanes of this design with pump more cool air through the brakes at speed.

The significant upgrade from OEM comes from the width of the rotor and the sophistication of the cooling vanes.  The stock system with Carbotech XP10s handled the track fine.  The pedal feel wasn’t great after a couple laps on 100 degree days, but that was likely related to tread squirm on the Hankook RS3s.  After a single day, however, the outer edges of the stock rotors were white.  This suggests they got extremely hot which usually leads to shorter rotor life and cracking.  Replacement rotors however only cost ~$50 a corner, so you could go through a lot of them before the Essex brakes become the smart financial decision based simply on longevity.

Ignore the AP Racing 4 piston calipers and the high end rotors, the Sprint kit should be attractive to performance junkies for one reason.  They shave 10 pounds of unsprung weight off each corner of the car.   The loss of this weight gives better steering feel, even on the street.  For performance calculations, every pound of unsprung weight is the equivalent to about 7 sprung pounds.  So the loss of 20 lbs off the braking system is the same performance differential of ditching a passenger from the cabin.

Every other silver painted caliper I’ve ever had has turned brown with heat. I look forward to trying to do the same thing to these.

The installation of this kit requires only a basic tool set that includes metric crescent wrenches and sockets with the exception of a torque wrench, a 10mm hex key, and the bizarre requirement of a unibit. My intention was to provide step by step instructions on how to install the system, but I was really impressed with what Essex included.  They were very detailed and explained everything step by step.  Consequently, I won’t make redundant their work.  The only real issues not anticipated by the instructions were the following:

  1. You can see the buggered nut on the OEM solid brake line

    This particular car had undercoating or a rubberized sealer sprayed on the brake hardline threaded connector.  Consequently, the threads were gummed up and these 10mm flare fittings stripped when just using a crescent wrench.  I ended up soaking the fittings with brake cleaner and using channel locks to get them to brake free.  An annoying complication, but this issue potentially wouldn’t exist in other chassis if the undercoating or sealer wasn’t applied in this manner.

female brake fitting doesn’t fit into stock bracket

2.  When the new steel braided line was being installed, I discovered that the female fitting that attaches to the OEM hardline does not fit through the stamped steel bracket designed to secure the brake lines to the chassis.  As you can see from the picture, the hole size is close to the same, but unfortunately, not close enough.  The fix was to unbolt the bracket from the car and use a unibit to drill it out.  To be clear, I don’t really see this as an Essex issue as much as one of the supplier of their brake lines.  When I raised this issue to Essex, they quickly looked into it and are making adjustments to the future kits that get shipped to customers.  So I suspect this won’t happen to other buyers.

One of the benefits I probably wouldn’t have paid for, but really appreciate is how easy pad swaps are.  By removing the single dowel pin with a hex key, you simply slide the old pads out, and put the new pads in.  I’ve been too lazy to swap pads on the stock calipers, so I’ve been running around with loud and dusty race pads on the street.  These calipers will make the swap to street pads a snap, so I’ll be more likely to do it.

quick swap brake pads

one last glamour shot before they get dirty on the track tomorrow

Igloo Case for iPhone 4

Next stop is the race track.  Sunday the 7th at AutoClub Speedway in Fontana is a www.Speedventures.com track day where we will put these through their paces.  At the same time is “86 Fest”.  I’m not a car show guy, but I do appreciate vendors and others supporting a car I’m interested in.  During this event we will also be the releasing  the IglooCase (ww.igloocase.com).  This case encloses your iPhone and adds a lens and camera mount. Prototype versions have been around for a season, but we just received our first 300 production pieces this week.  The cases will be order-able off the website in the week of 10/7/12.  At $59 plus a mount, it’s a cost effective alternative to a contour or go pro if you already own an iPhone.  I’ve called this product the title sponsor of this car, but the reality is its way more personal than that as I’m one of its creators.  Come by and check it out if you are at the track Sunday.  I’ll be under the 949Racing tent.

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