The 2.0 16v YBB engine has been around for sometime now and was available in several different forms as the years went by. (Designated, YBB, YBD, YBP, YBT, etc) There are certain cylinder heads that are preferable to use over others due to their increased stiffness and improved water ways, and NMS can advise the best route to follow. Likewise the earlier YBB engines used a "205" block derived from the 2.0 Pinto. This unit is capable of handling up to 350bhp but this is dependant on block casting quality (i.e. due to core shift) and bore size (i.e. the block is weakened by overboring). When I specify a 300+bhp engine I always advise the use of the later "200" block which incorporated additional reinforcement around the block sump face webs and block bore casting as well as some other minor block revisions.
All Cosworth engines are getting old these days and careful consideration must be paid to engine condition before carrying out any modifications. Although the EMS is relatively simple by modern day standards there are still a number of engine based sensors that are prone to failure or just old age. The phase sensor found in the distributor is prone to corroded wires that crack and break up and is a common cause of misfire. Likewise the TDC sensor is another common cause of engine problems and its condition and air gap should be checked for correct operation.
A lot of the earlier cars are now suffering with ageing wiring looms, and old ECU's. Issues are common with poor pin connections on the EMS system and again should be inspected and tested when trying to diagnose an engine management fault.
With any Cosworth that
I modify the very first port of call is a full engine check over, and
evaluation, so that the very best advise can be offered. There is little
point in raising the boost and power output on an engine with poor
cylinder compression and/or excessive piston blow by and likewise a worn
turbocharger will last no time at all.
