Anybody know why the 5 valves per cylinder?

[Vex182]

Just wondering if anyone actually knew why the 5 valves works better than a standard twin cam with 4 used in these engines? I know the 2 are laree than the other 3 but still can't see the advantages.

 

[<tuffty/>]

Multi-valve - Wikipedia, the free encyclopedia

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[vfr800]

vorsprung durch technik mate!

 

[badger5]

said Yamaha

 

[Andrew@A.L.D]

Because it has 5 valves per cylinder it doesn't mean its a good flowing head.

The cams in the 20v engine aren't the best and to make the most of the head and valves they need better cams.

 

[badger5]

although it is a good flowing head...............

the design was'nt ultimate power but wide torque spread.. non turbo type power delivery
thankfully they also made earlier engine largeport for those with higher airflows.

port velocity being important of course to performance more than overall "flow" through it

2.0tfsi's have dropped the 3rd inlet for somewhere to stick an injector.. and also bumped up compression ratio's and have great response and torque spread.. atmo CR on them plus a turbo...10:1 and above.. I can see why I see more references to folks "needing" stonger head bolts on tfsi's, vs 1.8t's on those pushing them a little harder now. Cyl pressures will be high

 

[Andrew@A.L.D]

although it is a good flowing head...............

Very much indeed

 

[Sam_]

9.25:1-9.5:1 is the sweet spot on the 1.8T isn't it?

Andrew: Do you use the MK4 TDI crank for 2067?

 

[Andrew@A.L.D]

yes sam