thexav Pro Tuner Staff member Points 407 Car 2002 Clio 172 19 January 2020 #1 I might be missing something here, but what is the difference between an 8 valve engine if it had large valves, and a 16 valve engine? Surely the gap the valve makes is more important than the number of valves?
I might be missing something here, but what is the difference between an 8 valve engine if it had large valves, and a 16 valve engine? Surely the gap the valve makes is more important than the number of valves?
TCJBOLDIE Moderator Staff member Points 767 Location Brisbane Car 2011 Honda FN2 20 January 2020 #2 For starters big valves need heavier springs and that puts more load on the valve train and cam lobes.
For starters big valves need heavier springs and that puts more load on the valve train and cam lobes.
obi_waynne Administrator Staff member Moderator Points 1,157 Location Deal, Kent UK Car A3 1.4 TFSI 150 COD 20 January 2020 #3 Also some 16 valve engines only use 8 valves at low rpm and all 16 at high rpm to give a good balance of power and economy. Interestingly Audi on their 1.8T head used 2 valves for the exhaust but 3 for the intake making it a 20 valve engine.
Also some 16 valve engines only use 8 valves at low rpm and all 16 at high rpm to give a good balance of power and economy. Interestingly Audi on their 1.8T head used 2 valves for the exhaust but 3 for the intake making it a 20 valve engine.