The Dunlop MSA British Touring Car Championship-winning K20C engine used in the Halfords Yuasa Racing Honda Civic Type R has been named Race Engine Design of the Year at the annual RACE TECH World Motorsport Symposium.

Under the skin, it’s basically the same turbocharged powerplant as you’ll find in a road-going production Honda Civic Type R – the 2.0-litre engine was developed for the BTCC by Neil Brown Engineering.

The use of this engine marked the first time an integrated exhaust management engine design has been devolved and raced – making the triumph in the Drivers’ Championship with three-time winner Gordon Shedden at the wheel all the more impressive.

Honda (UK) boss Philip Crossman said: “For one of our powerplants to be recognised for its performance and reliability in a race environment is a fantastic achievement.

“And triumphing after only one season of competing just goes to show the quality of what we produce and what Neil Brown can tweak. Here’s to more of the same!”

James Rodgers, Team Manager at Halfords Yuasa Racing, added: “The engine has been absolutely outstanding this season – it is a given that the team at Neil Brown Engineering can produce both race and championship winning engines – but to be recognised by the industry as the best race engine design is phenomenal in its first year.”

RACE TECH featured the unit in its most recent issue – in shops – analysing in great depth just how the BTCC was won this year with the K20C.

Here’s an excerpt: 

In many respects the K20C is a leap forward, with turbocharging and direct injection already designed into the production unit.

It’s an engine that suits the role of a high performance road car very well, but some of its design features proved to be more of
a challenge when adapting it to be a race engine. Chief among these is the integrated exhaust manifold, which is designed primarily to reduce emissions on the road car.

In essence it eliminates the traditional exhaust manifold, instead integrating the exhaust primaries into one outlet before they leave the cylinder head.

For a road car, this minimises the distance before they reach the catalytic converter and hence reduces heat loss. This means the catalyst takes less time to get up to operating temperature, reducing cold start emissions. It also generally has the effect of simplifying the exhaust design, saving weight and reducing costs; all of which are win-win for a production engine.

For a race engine things aren’t quite so straightforward. Keeping the exhaust energy up is good news for the turbocharger, but it puts more heat into the water jacket, which then needs to be dissipated. It
also creates issues for the exhaust tuning, because the length and diameter of each pipe is effectively set in stone (or at least cast in aluminium). Plus, almost by definition, packaging four exhaust tracts into one across a short space leads to very uneven primary lengths. 

…

“An awful lot of the work on this engine stems from the fixed geometry of that exhaust,” explains Neil Brown Engineering Managing Director, Neil Brown. “We carried out a lot of 1D simulation using GT Power to get the breathing right. Some of the parameters
we didn’t have at the time, but we used as much as we could from the previous engine and experience. In the end it turned out we were very close.”

This is the first time the company has used simulation so extensively on a project and it’s really come into its own, comments Brown: “We were able to reach solutions a lot quicker than we would have done traditionally.”