Originally based on the 1972 Ford Pinto platform that would have been lucky to hit 100HP, at the Goodwood Festival of Speed we spent a bit of time chatting to Julian Godfrey who you may recognise as engine and electronics mastermind behind Ken Block’s ‘Cossie V2’ build to find out what it takes to develop the now legendary 2L 4 cylinder YB Cosworth engine to produce 600-700hp reliably and even surpass that magic 1000hp mark.
With many of Julians builds being used for rally and rallycross racing which employs the use of restrictor plates, a lot of the power and torque developed needs to be low down in the rev range which can essentially double the amount of time the engine internals are required to withstand the incredible pressures that a high output of torque produces. To give some figures, around 700ft/lbs (949Nm) of torque and up to 46psi (3.2bar) of boost will be produced low in the rev range.
Cylinder head sealing is discussed and how a Coopers Ring (aka Wills Ring) works along with the use of Nikasil and titanium nitride coatings, aftermarket sleeve technology and the pros and cons of both ductile iron and steel liners including their limits. The inconsistency of factory castings, how Julian entered into the motorsport industry and got involved with the YB Cosworth platform via Ford Sierra rally cars and then, of course, the Ford Escort.
Also covered are some of the major design changes that are required to the YB block and set up to handle the 200ft/lb to 700ft/lb torque jump including the use of a billet sump that helps improve and spread the clamping load required to keep it all together along with some of the major differences between the areas of focus on a road vs race engine.