A Cost to Benefit analysis of a Brake Duct system to track day enthusiasts

Faded brakes resulting in reduced stopping force remains a constant concern when attacking our favourite
tracks. Spongy brake feel culminating in heart stopping moments and inability to brake well, on the way
back from the local track are typical. We spend hundreds, if not thousands, of dollars on modifications to
increase the braking ability of our beloved rides and enjoy the results when tracking.

A moment of reflection leads us to ponder if this money was well spent. Could money saved on excessive
brake modifications be better used on items such as better suspension or even other safety equipment? This
article looks to examine and promote meaningful and practical discussion, by way of cost benefit analysis,
the effectiveness of current expenditure regarding braking modifications and their practical impact to track
day enthusiasts.

A simple understanding of the brake system is necessary for us to begin. The friction generated between the
brake pad and the rotating brake disc converts the energy of the moving vehicle into heat. The heat is lost
through the surface area of the disc to air when the car is moving. Build up of heat in the disc will mean;
generation of heat is at a rate higher than the ability of air to dissipate the heat of the disc quickly enough.
Faded brakes, spongy brake pedals, burnt discs & crumbling brake pads are all symptoms of a simple
problem of too much heat in the braking system. I will use a virtually stock Honda S2000 (unmodified
except for a bolt-on exhaust & sportier alignment) tracked at Sepang International Circuit as a reference.
Tracking the S2000 on stock brake components proved a bad idea considering the searing >50 Degree C
track temperatures. The stock brake pads quickly disintegrated with 80% thickness pads dropping to 10%
in one 3 hour track session. The stock brake fluids boiled after a few laps & remained dangerously spongy
even after a long rest in the pits. The brake discs turned a funny burnt tinge after a taxing session and
smoke could be seen pouring off them on entry to the pits.

Upgrades to address these issues soon followed by way of Ferodo DS2500 brake pads (which are rated
from 50-750 Deg C), stainless steel brake lines and Motul RBF 600 brake fluid for a total cost of about 800
SGD including labour cost (Note: Labour costs may vary from workshop to workshop). The rate of wear of
the pads was halved and sponginess was staved away. Brake fluid changes could be done after every other
track day although lapping the track was still limited to about 5 hot laps before the brake fade began to
worry the driver. The condition of the brake discs remained relatively unchanged.

This meant the heat experienced by the system had clearly not changed. However, certain components
were now able to handle the heat slightly better. A possible reference to how much deep braking was used
was that the confidence level to begin threshold braking for Turn 1 had grown so much so that the driver
was confident to brake just before the 100m marker to still make the corner for at least the first half of the
track session. Braking that late for the latter half of the session was risky as brake fade had begun to appear.

The next step, to most of the tracking community, would certainly be obvious. To increase lapping
longevity (to get as many hot laps per track session to maximize seat time), further brake modifications
were necessary. 4 pot monoblock calipers, even higher temperature brake pads and bigger discs, at least for
the front brakes, (at a cost ranging from 4000 to 6000 SGD from brands such as Project Mu or AP Racing)
would need to be fitted to generate more powerful & consistent braking.

There is no doubt on the benefits such modifications confer. However, would it be possible to have
approximately 80-90% of the benefits at a lower cost? Tracking isn’t the cheapest of hobbies and being
cheap on vital components, such as brakes, isn’t something most enthusiasts want to be seen doing and yet
the cost of a “proper brake” upgrade system is clearly prohibitive to many. Perhaps we should examine
more closely our desired brake performance objectives.

Upgraded stopping power is greatly desired. A simple explanation of braking “power” is that an increase in
the braking “power” can be defined as a small application of force resulting in a larger than typical braking
forces. One could upgrade the brake booster (master cylinder) to get this result or simply step harder on the
brake pedal. The S2000 test car with stock tyres achieved >1G of braking on the front straight without the
use of a big brake kit so clearly there was no lack of braking power, however, a big brake kit would greatly
improve modulation characteristics under threshold braking.

To address brake fade and a spongy brake pedal, another S2000 fitted a 4 pot big brake kit (including large
calipers & upsized discs) from a leading brake manufacturer and achieved good consistent braking but fade
still begin to rear its ugly head by the end of the 3 hour track session. Brake fluids did boil a little less, fluid
change intervals were slightly increased but 3 track sessions on the same fluids would probably the
absolute limit. A definite improvement, to be sure, but it was clear that the problem of fade still remained.

The S2000 test car was then modified with a commonly overlooked modification, namely, brake ducts. The
initial setup was with ducts channeling air by a regular piping to the calipers on all four corners, evolved to
add a funnel head on each pipe to concentrate air flow to the same 4 calipers and finally to a setup where
both front and rear brake discs and calipers are individually cooled with their own piping. The total cost for
ducting and fitting (all customized) was approximately 800 SGD.

Testing of the system was done over the course of a year with 7 track days at both Sepang International
Circuit & Johor Circuit and the results were: With the same Ferodo DS2500 brake pads & Motul RBF 600
brake fluid on the stock brake system, brake pad life was increased to at least double of the usual service
interval while discs ceased to smoke and exhibited no visible burn marks.

The result with the brake fluids was not only that sponginess was eliminated for all the track sessions and
not evident on the 300km drive back to Singapore, >5 laps could be easily done without a hint of fade,
braking could be done consistently on every lap at the 100m marker without fade appearing and no change
of fluids appeared necessary even after the 7th track day. The S2000 test car could now repeatedly do
multiple stints of >15 hot laps without fade on the stock calipers & discs which is clearly a huge
improvement in fade resistance over even usage of an expensive big brake kit.

An added potential benefit, which is not immediately evident, could be that of the heat being taken out of
the drive train components (such as CV joints and wheel bearings) thus reducing the heat stress on them
and possibly prolonging their lifespan. Usefulness of brake ducts is nothing new in racing (virtually every
race car has them) but strangely a search within some aftermarket brands concluded that you will be hard
pressed to find them selling an effective and comprehensive brake duct solution in their product ranges.
The downside of such a system would be some time spent to customize a proper system, maintenance of
the fittings and probably some hindrance to certain modifications as the ducts would require some space to
fit. The benefits are, however, numerous and obvious to the track enthusiasts. These would be namely, cost,
maximizing seat (practice) time, safety and prolonging the lifespan of various components in the car.

This article does not suggest one should replace a big brake kit with brake ducts, however, every track day
enthusiast should consider to have a brake duct system in place to complement their existing brake setup.
The actual cost and benefit derived varies car to car and with the type of brake duct system constructed.
More data will serve to cement the ideas listed herein and it is this author’s intent that such discussions will
serve to usher a more measured and practical approach to safely enjoying tracking as a hobby.

Written by Norman Souza Tan

The Berjaya Hills Time Challenge 2009

The Berjaya Hills Time Challenge 2009

The Berjaya Hills Time Challenge in Malaysia is not a speed hillclimb but a precision event for supercar, performance car and classic car owners where competitors are encouraged to drive quickly but at the same time in controlled manner up and down the 8km course. The winner is the driver who selects a time for both the up and downhill drive and then attempts to match it 100% (no timing devices allowed)
Total time must include the 5 sec countdown and a final 100 metre zone which must be driven at
30kmh. The attached video is of a Ford Focus ST on the 2009 downhill run. The target time for this runwas 6:50 min. Time achieved was actually 6:02 (clearly much too quick). 2009 was the first year for this event which is hoped will become an annual gathering for motorsport and car enthusiasts throughout Malaysia, Singapore and region.

TAKE OFF …. Ford Focus ST makes a quick getaway for the downhill
What can I say other than this was a truly fantastic event and one of the best motorsport weekends I’ve attended in years. Around 120+ supercars, performance cars and classics from Ferrari, Lamborghini, Porsche, Aston Martin, Lotus, Bentley, BMW, Mercedes, Nissan, Ford, Honda, Subaru, etc etc. Also you’ll be pleased to hear I was not the only Ford on the hill. I was accompanied by a fellow Ford fan from the classic car category who attended with his Ford GT40.

Met some great enthusiasts of all ages and nationalities and enjoyed talking about cars every evening until the early hours of the morning over some local makan and cold beers ….. Excellent!
And so to the event: The Friday brief started with a full explanation of what was required of us which in simple terms was as follows:
As I mentioned in an earlier post this was not an outright speed event but a time challenge. Every competitor got at least one practice run up and down the hill with the road fully closed. During these practice runs you were allowed to time yourself by any means at your disposal (watch, clock, stopwatch whatever). After that you had to select a target time for your run of between 6 minutes to 10 minutes. This time had to include the 5 second countdown at the start and a final 100 metre section at the end of the run which needed to be driven at 30kmh. Total distance 8km. I think this system is good as the event is then open to everyone regardless of their driving skills and all participants stand a chance of winning. Fun was the order of the day and I think that is exactly what everyone experienced.

There were a number of categories:
1. Too Fast too Furious – At the briefing this described all those with a right foot larger than their brain.
2. Expert – Regular racers or anyone involved in organizing this or previous events on Bukit Tinggi
3. Gentleman’s Category – The silver haired brigade (which included me of course)
4. Classic Cars – Anything over 35 years old of which there were quite a few including a V12 E-Type, Ford GT40, Lancia’s, Alfa’s and a Lotus 7 replica together with some early model Porsche 911’s.
Category 1 proved correct during practice as one guy ran out of tarmac with his Playstation 3 (Nissan GTR) and into the wall half way down the hill – GAME OVER. The car finally came to rest on its side in the storm drain where it remained for the rest of the afternoon while they found a truck big enough to pull it out. Driver was ok and returned the next day with a different car from his stable: a classic Alfa Romeo GTV (far more docile). It wasn’t a great day for one BMW Z4 owner either as he reshaped the car quite extensively against the Armco barrier before again coming to rest in the ditch. Thankfully the driver was again unhurt.

The second challenge was the Forest Time Attack. This consisted of a slalom / obstacle course set up on the roof of the multi storey car park. Competitors were required to take 3 runs round the course with the fastest recorded time in each category being put forward for the final competition.

During the downhill practice session I forgot to take along a stopwatch so had to guess a time from the cars digital clock. However, I managed to borrow one for the uphill and recorded a best time of 5:47 which is an average speed of 83kmh. This says a lot about the torque of the ST considering I was going uphill and in either 3rd or 4th gear the whole way. Anyway, for the actual run I decide to target a time of 6:50 which would allow for the countdown and the final 100 metre section requiring a speed of 30kmh. This also gave me a small margin in case of rain (which we did get during the later part of the Friday practice).

On Saturday, with watches removed and all car clocks taped over, (hopefully nobody cheated) the downhill runs came first and I registered a time of 6:02 way faster than my declared target time so a bit of a screw up there but great fun none the less.

Downhill Video: http://www.youtube.com/watch?v=L6z51w83_BU

As we lined up for the uphill runs in the afternoon I was car number 5 in the line up and sure enough as the time came to start we got a typical Malaysian downpour of rain. Fortunately this only affected about the first 2 to 3 km of the hill with the rest remaining dry. As you can imagine those first few km’s were pretty hairy with a healthy mix of wheelspin and understeer all in evidence on the narrow road as I made my way up the hill. As you can guess I had to drive like a lunatic on the remaining dry section resembling a member of the Too Fast Too Furious category rather than a gentleman on this occasion and eventually clocking 6:08 mins. A bit too quick again as I registered a target time of 6:20. Sorry guy’s no video of the uphill run (forgot to turn it on). Must have been the panic that set in with all the rain when only yards from the start line.

The following links show the absolute times from the Berjaya Hills event both up and down.
The first thing to remember when reading these is how they are calculated.
1. After stopping in the start box you are clocked in and handed a time card
2. At the same time a guy in front of the car counts you down from 5
3. When you reach the bottom you then had to drive the last 100m at 30kmh
4. You hand the guy the card (if you haven’t lost it on the way) and he clocks you out.
The time taken for all this process added up to about 25 seconds to the true time. In a proper speed hill climb in the UK the timing starts when you break a light beam at the bottom and stops when you break a light beam at the top. Or vice versa.

See link for down times: http://www.keepandshare.com/doc/view.php?id=1454273&da=y

See link for up times: http://www.keepandshare.com/doc/view.php?id=1454274&da=y

According to these lists I was the 4th fastest car down beaten only by 2 Lotus Elise’s and a Porsche GT3, and the 4th fastest car up beaten only by a heavily tweaked Scooby STi an Audi R8 and a Golf GTi. In each case I was beaten by no more than 5 seconds over the 8km. Considering some of the machinery in use on the day I think this was pretty good going for a lowly shopping trolley like a Ford Focus ST. Bring on the RS.

The event was finally won by a member of TCC driving a Honda CTR who recorded 100% accuracy on both his uphill and downhill times which was quite a feat. So no prizes on the hill for the ST. However, I did win second place on the slalom / obstacle course with a time of 23.16 seconds which is not bad considering that the ST has a turning circle like an oil tanker on a course that was considered pretty tight by most. Saturday closed with a gala dinner / prize giving ….. and loads of cold beer after a hard days work.

At this event everyone was a winner, and apart from a trophy I also left with gifts from sponsors, which included Selangor Pewter, T-shirts, caps, auto magazines and 10 litres of synthetic motor oil.

On Sunday we all headed off in convoy for lunch down to the Selangor Pewter factory in KL. This was an amazing sight with around 100 cars all hammering down the E8 highway. With every car carrying numbers and an array of sponsor’s stickers; it looked more like the Cannonball run or Wacky Races. Great sight to see.

As we approached KL the organizer had arranged for a police escort of 8 outriders which was even more amazing as this massive collection exotic machinery made its way through the streets of KL with red lights ignored and junctions made clear for our arrival. I felt a bit like the president arriving After lunch we then headed off for an afternoon of more driving action at Sepang F1 circuit which, although closed in preparation for the Moto GP, was opened especially for us to play for 3 hours. A full police escort for the convoy was again in evidence with the FOCUS ST as lead car. I should have had a TCC flag flying from the aerial.

Escort to Sepang video: http://www.youtube.com/watch?v=5EJBwDvDwOg

Once at Sepang I accepted the invitation of a couple of guy’s I had met at the event to have a drive of their cars ……. Wait for it …. A Porsche GT3 RS (awesome) an Aston Martin V8 Vantage (I’m in love with a car) and a classic Lotus 7 Replica (I’d forgotten just how drafty they are)
The organizer plans to make this an annual event and I for one will be going again for sure.

Hope more of you can make it next year

Ian Porteous