Work that EVO VIII. by Alex Butti

Posted by

By now most of you have heard that the Sierra Sierra Enterprises has broken the record at Buttonwillow a couple of weeks ago. It was a feat, considering how many cars have been trying to chase the record but always fell short.
What is more impressive is not the actual-official lap time (1:43.430, although they ran an unofficial 1:43.200) but the fact that it took Sierra Sierra Enterprises only a year of development to achieve this goal. Taking also into consideration that HKS had been working on their Lancer EVO’s since 2002, you gradually start to understand what an achievement SSE accomplished. I said 2002 because HKS developed the EVO TBR-02 around that time (hence the 02). HKS spent countless amount of time doing R&D, collecting valuable data and they ended up destroying the car at Tsukuba (thanks to Nobuteru Taniguchi). All that work was not wasted though, because the information gathered through the TBR-02 was used toward the CT230R. For years the CT230R had been breaking records left and right. Most of you recall what happened in 2007 at Buttonwillow. HKS came, conquered the track and left a bold statement on the US soil (with a lap time of 1:43.523). That was until March 28th 2010.
Let’s take a closer look to this EVO VIII.
First of all, the SSE EVO does not sport a dry carbon fiber bodykit like the CT230R, but wet carbon panels thanks to Kaminari. Wet carbon fiber is heavier and more fragile than dry carbon fiber, as the resin and the hardening are not distributed homogeneously. This means that the car weights a bit more than the CT230R. Roughly 2750lbs. (the HKS CT230R weight about 2370lbs.).
What it lacks in “silhouette” though it makes up in aerodynamic. As you can see from the picture above, the car resembles very much a DTM racecar. Under the SSE EVO’s belly, there is a sheet of carbon fiber (dry) that runs along the car, from the front splitter to the rear diffuser, which in term it helps to keep the air-turbulence to a minimum. The carbon sheet helps to speed up the air underneath the car helping the chassis to be more stable at high speed. It is a very basic aerodynamic concept.
Here is a closer look at the front end:
Much like the CT230R, the SSE EVO lacks front lights and blinkers (for obvious reasons). The square-looking holes seen above provide fresh air to the oil coolers, while the canards ensure more front bite on the front tires (again, simple aerodynamic concept). Speaking of tires: this EVO wears Hankook C91 DOT tires (275/35/18) wrapped on Advan RS wheels. Although the cars also runs on Volk CE28n’s and TE37’s.
I know some of you are curious to know what’s under the hood. So here it is:
The long block was entirely built by Cosworth, using their 2.2L forged-stroker kit along with Cosworth headgasket, head-studs and valvetrain, with of course bump sticks (280 duration for the intake and 272 duration for the exhaust. Unfortunately I do not know the lift of the cams).
Other bits of the engine are: Full Race exhaust manifold, Garrett twin-scroll turbo (I do not know the spec of the turbo sorry), a Kansai Service intake manifold, dual TiAl wastegate, TiAl BOV, C&R radiator, custom I/C, and lots of Wiggins clamps. (Wiggins clamps are expensive but provide the best seal possible and are tested to support up to 125 PSI of pressure). Along with the Wiggins clamps you also see that all the vacuum lines have been swapped with AN fittings to increase reliability.
You can also see that SSE/ Cosworth used gold foils throughout the engine bay to isolate the heat produced by the 560 hp engine from the ECU harnesses. Mil-Spec wiring was used throughout the car along with Raychem DR25 tubing to ensure insulation and protection; again, for reliability.
Here is where all the magic is orchestrated together. Cosworth’s very own Pectel SQ6 ECU, Pi GPS beacon, and Pectel EDC differential computers; yes, you read that right. This EVO’s differentials are tuned by separate computers.
What’s more to say? There is a NACA duct on the rear passenger’s lexan window that is connected to a 3” silicon hose which draws in fresh air to the electrical fan underneath the EMS, which helps to cool down the ECU’s. Cool eh?
Last but not least, the suspension and chassis tuning bits: the shock towers have been reinforced with steel plates, along with a FIA-approved rollcage, while 4 way Dynamic coilovers have been replaced the stock Bilstein struts. Surprisingly the stock control arms have been left alone aside from the spherical bushings and custom rear toe-arms.
As the picture shows, the rear (and front) stock swaybars have been ditched in favor of these custom mounted units. Very tricky pieces I may say. They can be controlled in the cockpit thanks to adjustable levers, which stiffen or soften the swaybars based on track layout.
Brakes duty is taken care of by Brembo GT magnesium calipers (6 titanium pistons up front, and 4 pistons in the rear). Of course there is an adjustable brake bias knob in the cabin to control the clamping force.
So the SSE EVO broke the record at Buttonwillow, but we all know that HKS has been working on their latest project; the CZ200S. Not to forget also is the Tarzan/ Tomei STi. I can’t wait to see what’s next.
That’s all I have to say for now.
If you want to see more pictures of the SSE EVO, check my link:

Be Sociable, Share!