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Tracker · 23rd July 2018, 22:17

Simon, I believe the following to be the actual press release by MG Rover when the MG ZT 190 was launched:

"The ZT range has newly-enhanced versions of MG Rover's all-alloy quad-cam V6 engine. For the ZT 190 models, several special features have been engineered to achieve the higher power output of 190Ps or 140kW, and increased torque of 245Nm.
Beginning with the variable length induction system, the air intakes have a 15% larger duct and a new intake diffuser. This provides a smoother airflow with less than half the usual pressure drop; it has also been tuned for a more sporting induction sound. Internally, there is a new inlet valve cam profile, advancing the inlet valve opening by 4°, as well as improved inlet porting.
To withstand higher cylinder pressures, the gudgeon pins and big end bearings have been upgraded, and the oil specification has been raised to ACEA-A3 for protection at sustained high revs.
A further contribution to performance comes from a new exhaust system, with 60mm diameter pipes in place of 57mm, new low-restriction metal-based starter and main catalysts and a modified rear silencer unit. This has larger-bore internal pipes, twin straight tail pipes and a mechanical valve that responds to exhaust pressure at around 4500rpm to by-pass the internal baffles.
This reduced back pressure helps create an attractive sporting note while still meeting all legal requirements for drive-by noise.
A redesign of the engine ECU software and specially designed MG throttle cams provide the right sporting feeling of responsiveness to the accelerator pedal, with a deliberate reduction of the normal throttle on/off damping.
Finally, an enhanced cooling system, with 20% greater cooling intake area, uses an improved-flow radiator and top hose configurations, with a new plate-type oil/water oil cooler replacing the oil/air heat exchanger"

The only difference with the inlet cams may be the 4 degrees of advance, but other apparently knowledgeable sources have said that the 190 and ZT 180 (not the ZS 180) exhaust cams have 8.8mm of lift and 244 degrees duration as against 8.2mm lift and 236 degrees duration on all other ZT and 75 engines. A check of the Rimmers catalogue shows that the part number for both inlet and exhaust cams is different for the ZT 190/180 engines to the ones on all other KV6's. I don't profess any technical qualification or knowledge on these matters - just an interested amateur.

23rd July 2018, 22:17	#12
Tracker Loves to post MG ZT Join Date: Sep 2015 Location: Dunmow Posts: 350 Thanks: 139 Thanked 83 Times in 72 Posts	Simon, I believe the following to be the actual press release by MG Rover when the MG ZT 190 was launched: "The ZT range has newly-enhanced versions of MG Rover's all-alloy quad-cam V6 engine. For the ZT 190 models, several special features have been engineered to achieve the higher power output of 190Ps or 140kW, and increased torque of 245Nm. Beginning with the variable length induction system, the air intakes have a 15% larger duct and a new intake diffuser. This provides a smoother airflow with less than half the usual pressure drop; it has also been tuned for a more sporting induction sound. Internally, there is a new inlet valve cam profile, advancing the inlet valve opening by 4°, as well as improved inlet porting. To withstand higher cylinder pressures, the gudgeon pins and big end bearings have been upgraded, and the oil specification has been raised to ACEA-A3 for protection at sustained high revs. A further contribution to performance comes from a new exhaust system, with 60mm diameter pipes in place of 57mm, new low-restriction metal-based starter and main catalysts and a modified rear silencer unit. This has larger-bore internal pipes, twin straight tail pipes and a mechanical valve that responds to exhaust pressure at around 4500rpm to by-pass the internal baffles. This reduced back pressure helps create an attractive sporting note while still meeting all legal requirements for drive-by noise. A redesign of the engine ECU software and specially designed MG throttle cams provide the right sporting feeling of responsiveness to the accelerator pedal, with a deliberate reduction of the normal throttle on/off damping. Finally, an enhanced cooling system, with 20% greater cooling intake area, uses an improved-flow radiator and top hose configurations, with a new plate-type oil/water oil cooler replacing the oil/air heat exchanger" The only difference with the inlet cams may be the 4 degrees of advance, but other apparently knowledgeable sources have said that the 190 and ZT 180 (not the ZS 180) exhaust cams have 8.8mm of lift and 244 degrees duration as against 8.2mm lift and 236 degrees duration on all other ZT and 75 engines. A check of the Rimmers catalogue shows that the part number for both inlet and exhaust cams is different for the ZT 190/180 engines to the ones on all other KV6's. I don't profess any technical qualification or knowledge on these matters - just an interested amateur.