Kami University:: Session 2- “Downforce”

Welcome back to K.U.

Subject:: Downforce

Downforce is a term used to describe the downwards force created by airflow as it passes the exterior of a moving object, namely cars in this case. The purpose of downforce, in an automotive sense, is to counteract lift (basically the opposite, where airflow passing a moving object causes it to lift off the ground). It is commonly used to ensure a car does not lose traction at high speeds and to allow a car to travel faster through a corner by increasing the vertical force on the tires, thus optimizing grip.

A Diffuser is a great example of a downforce generating automotive component. A diffuser is a shaped section of the car’s under-body, usually on the rear bumper, which improves the car’s aerodynamic properties by improving the transition from the high-velocity airflow underneath the car to the much slower free-stream airflow of the ambient atmosphere. It works by providing a space for the underbody airflow to decelerate and expand so that it does not cause excessive flow separation and drag. Thus the diffuser causes a more efficient flow of air, which in turn accelerated the underbody airflow which means more downforce.

Basically what all that means is the following:

  • Airflow when it hits the front bumper can either go above or below the car, either way the airflow accelerates as it compresses, which for the underbody causes a low air pressure and creates a “suction effect” thus causing downforce
  • A rear diffuser allows the underbody airflow to efficiently expand and decelerate back into the atmosphere
  • By improving this transition the diffuser allows more airflow to decelerate, allowing the underbody to have increased airflow which in turn increases underbody airflow acceleration
  • Increasing underbody airflow acceleration means lower air pressure in the underbody and thus more downforce


Shinmoedake Peak Erupting in Japan

An aerial view shows Shinmoedake peak erupting between the Miyazaki and Kagoshima prefectures January 27, 2011.  Ash and rocks fell across a wide section of southern Japan straddling the prefectures of Miyazaki and Kagoshima on Thursday. As one of Mount Kirishima’s many calderas erupted, authorities raised alert levels and called on for an evacuation of all residents within 2 km (1.2 miles) radius of the volcano.

This is a pretty sweet image of lightning hitting the volcano.

Video Game Drivers FTW, Not Really haha

Continental Tires ran a questionnaire among 2000 drivers (half gamers, half non all between the ages of 17 and 39) asking them driving related questions. The results aren’t surprising, but they’re definately interesting. Video-Game Drivers FTW!!! We may be more reckless… but at least we’re better drivers.

Drivers Who Play/Don’t Play Video Games
% Stopped by Police
% Who Use a Cell When Driving
% Ever Reported an Accident
% Ran a Red-Light in the Past 12 Months
% Driven Wrong Way on 1-Way Street
% Hit a Stationary Opject While Parking
% Hit and Run
% Take Risks (accelerate too quickly, overtake)
% Suffer Roads Rage
% Speed
% Scare Others w/ Their Driving
Average Attempts Before Passing Driving Test
Average Number of Dents in Past 12 Month




The Celica from Hell

When we think Toyota Celica not much comes to mind, very few have ever tuned the 7th Generation Celica to it’s true potential. Mostly because of its less than impressive base features. When we start a project car initial power and performance is always good, but the skill of a tuner sometimes comes from taking a seemingly unimpressive Toyota Celica and turning it into a 4-wheel drive 700 horsepower 9 second monster.

I’m pleased to give you our friends over in the UK: The Fensport Celica GT4 X

Having created the UK`s fastest Front & 4wd wheel drive Corolla`s, we decided it was time for a change in direction and try something new, but we still wanted to retain that “shock factor” that our corolla is so famous for, so we decided to build a celica – the new celica, the generation 7.

We wanted to create the best all round track / drag celica the UK has ever seen so we started with the generation 7 TRD M Sport. This limited edition special model is factory strengthened for motorsport use, making it an ideal base, it is also much lighter than the previous celica gt4 models .

We started the theory side of the project back in august 05 and started measuring and working out what parts may fit or be required. Then in October 2005 the real work started with delivery of the car and the very first job was the 4wd conversion and the 3sgte engine installation, this was acomplished using a variety of standard toyota parts from the celica, the 4wd corolla and the GT4.

The car has been built with all round performance in mind, it will compete in a wide range of events including Ten of the Best, Time Attack and Drag Racing Events.

Stage 1: November 2005 4wd & 3sgte Conversion

Stage 2: January 2006 Roll Cage/ Intake Manifold / Engine Bay Build / Fuel System

Stage 3: March 2006 Final Engine Build/ Testing

Power: 800bhp
Torque: 550 ft/lbs
Weight: approx 1120kgs/2470lbs

Official Figures
Top Speed: 202.22mph
Quarter Mile: 9.74 @ 149 mph

Data from Racelogic Performance Box in damp conditions
0-60 in 3.15s
0-100 in 6.01s
0-150 in 11.75s
0-200 in 26.17s
0-200 in 1.01 miles

Technical Specifications:


  • The floorpan of the car has been slightly altered to accept prop-shaft center mount and an exhaust tunnel, the rear spare wheel well has been removed, and the fuel system installed where the back seat once was. No chassis rails have been cut, however 2 towers welded in to locate 4wd corolla rear sub-frame, which is modified to accept the GT4 rear differential. The rear hubs are also from the corolla 4wd.
  • Front Cross-member is from corolla 4wd and modified for 3sgte engine /transmission, all engine mounts are custom made.
  • Front radiator support panel has been replaced with T45 steel member to straighten up both inter-cooler and radiator to aid airflow and also increase engine bay space.
  • The A,B & C pillars are strengthened via extra spot welding at the factory by TRD.
  • The extensive roll cage is a fully tig welded wrc type multi point, links to front turrets, transmission tunnel, rear turrets and double X door bars. The under dash bar is also incorporated into the cage.
  • The front bumper bar is replaced with T45 steel
  • The rear bumper bar is lightweight alloy
  • 2 extra rear chassis stiffening under-braces in aluminum support carbon boot floor.
  • All under-seal and sealant removed.
  • Doors lightened and internal door bars removed, 8.5kgs per door saved, electric windows and glass retained.


  • The engine is the 3SGTE, 2.0 liter twin-cam 16 valve turbo, as used in both the MR2 Turbo and Celica GT4, using a TTE Group ‘A’ block and TTE crankshaft, capacity is standard 2.0 liters. Crower steel connecting rods with custom JE Forged Pistons, ARP Bolts, metal head-gasket, Lightweight alloy pulleys.
  • Fensport Racing ported and flowed cylinder head with racing valves and double valve springs, TTE vernier pulleys and HKS 272 degree camshafts.
  • The inlet manifold is completely custom made to suit the new Celica installation and has a short runner design with internal ram pipes and a 75mm throttle body.
  • The fuel system is completely custom and installed where the rear seat would have been, The tank is alloy and foam filled, holley lift pump, swirl pot then aeromotive main pump, -10 braided fuel lines, 1000cc injectors and aeromotive fuel pressure regulator.
  • New for 2010 is the turbo, now a Garrett GT35 Billet unit using a a smaller 0.63 AR exhaust housing, mounted on a Corolla WRC manifold modified to accept a TIAL 44mm remote wastegate which is now vented back in to the main exhaust to comply with noise regulations. This new set up provides better response which is needed for the Toyota Sprint Series, this setup produces great response and approx 630bhp.
  • 2010 Drag setup uses a larger 0.82 ar turbine housing and a 75 shot of nos.
  • The exhaust system is stainless steel, using 90mm mandrel bent pipework from turbo to single back box with a Blitz Nur Spec R custom rear silencer.
  • GT4 alternator modified with corolla regulator and Fensport alloy oversize pulley, TTE wrc alloy mount with carbon adjustment bracket..
  • Custom breather system with stainless braided pipework leading to a custom alloy tank with oil return line. Also incorporates the power steering reservoir.


  • A Blitz front mounted inter-cooler, from the supra JZA80, is used with custom made “lightweight thin wall” 0.9mm stainless steel 3″ piping and Samco silicon hosing.
  • The ERL water injection system is controlled by motec, and keeps the intake charge cool, a Digital dash display 3 informs the driver of water flow.
  • The cooling system has a custom alloy radiator, electric water pump, alloy header tank, swirl pot, a trd low temp thermostat and Evans coolant.
  • Twin oil coolers with braided lines and thermostat.
  • Gearbox oil coolers
  • Samco Hoses


  • Fensport Racing Triple plate clutch with lightweight flywheel
  • Fensport Racing 5 speed straight cut, dog gearbox with a low ratio 4.4 straight cut final drive. Ikea sequential shifter.
  • Cusco MZ plate type Rear LSD
  • TRD rear differential front mounts, Fensport Racing uprated rear diff mount.
  • Prop-shaft retaining rings.


  • The Front suspension is AST 3 way adjustable coil-overs with camber adjustable top mount
  • SuperPro front wishbone bushes with increased castor and anti lift. SuperPro anti roll bar bushes.
  • Rear suspension uses AST 3 way adjustable coil-overs
  • Whiteline adjustable anti-roll bar with poly bushes from a MR2 turbo is mounted behind the axle..
  • Whiteline adjustable drop-links.
  • C-one lower rear arm bushes


  • Front – Tarox 10 pot GT caliper with 340mm discs
  • Rear – Tarox 6 pot caliper with 280mm discs
  • Braided steel lines throughout, all lines inside.
  • In car adjustable brake proportioning valve.

Wheels & Tires:

  • Volks Racing TE37, 7 .5 X 17 ET35 with Toyo R888 tires 215/45 for circuit and 225 for drag, Toyo T1-R 215/45 wets.


  • MoTeC M400 Pro ECU is used to control the engine as well as Boost Control, Water injection, Full throttle gear-change, Launch control, Data logging and Wide band Lambda.
  • Motec digital Sport Dash displays all ecu parameters as well as speed, gear position, shift lights, warning lights, oil pressure, fuel pressure, engine oil temp, gearbox oil temp, and rear differential oil temp.
  • Custom wiring loom throughout.
  • FIA electric cut out switch


  • Interior – Fully trimmed with flocked dash & interior plastics,headlining and carpet, custom made door and rear panels.
  • Recaro Profi Race seats (6kgs), Momo quick release steering wheel
  • Schroth 5 point harnesses.
  • Spa firefighter 4kg plumbed in electric fire system, 3 engine bay and 3 interior extinguisher jets.
  • Battery relocated behind passenger seat.
  • Alloy Water Injection and washer tanks in boot.


  • Varis Carbon fiber bonnet, with scoop for turbo clearance
  • Carbon roof scoop.
  • GT front bumper modified for more airflow and C-one front spoiler
  • Seibon Carbon fiber tailgate with tinted plexi-glass
  • GT side skirts
  • Varis GT Carbon rear wing
  • TRD M sport rear bumper corners


Fensport UK

Debut: GramLIGHTS 57V (Updated)

MSRP Pricing at $381 per wheel
I also have some more pictures up, contact us if you are interested.

New concept wheel from RAYS/GramLIGHTS.  They are the 57V, similar to the 57Vintage, where the V stands for Vintage/old-school.  It appears they’re only available in 15×7.5 for 4 lug applications. You know what that means right?  Hachi Roku time to get new shoes!



Rays – 57V