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Discussion Starter #1 (Edited)
Different Camshaft lobe heights

Hi guys , i was looking around for some sohc non-vtec engines that honda made .And i came across a D16B2 that was released in Europe in a 1998-00 civic 5 door MB model .This engine has stock 116hp and 143nm of torque .Which is one of the highest of the non-vtec engines .For comparison A D16y7 has 106hp and 140nm of torque ,A D16Y4 has the highest 120hp and 144nm of torque .
Upon further research i noticed this engine uses P2P pistons ( d16y8 ) has a y8 combustion chamber and maybe y8 ports ,but it does have a non-vtec camshaft. The oem part number of the head is only used on this engine , so a unique head and cam afaik.

I found a service manual which has the cam lobe height to check for wear.

What was weird is that this cam has different intake lobe heights .

They describe them as intake lobe A and B one is 35.019mm and the other is 34.734mm in height.Why would honda have done this ?Is it to improve the overlap ?
I wonder if it is because of this camshaft that this engine makes more hp then the others. It also uses a plastic intake manifold (model like D16y8 ) which flows like crap and it has a compression ratio of 9.6 :1.

Here are some other stock sohc non-vtec lobe heights :

D16Y7 : Intake 35.299mm Exhaust 37.281mm
D14A4 : Intake 34.848mm Exhaust 36.019mm
D16Y9/D16Y4: Intake 35.690mm Exhaust 37.904mm

D16B2: Intake A 35.019mm, B 34.734mm Exhaust 37.904mm
 

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Discussion Starter #2 (Edited)
I've found my answer ,Larry from Endyn said this :

"Since the first VTEC engines in the late eighties, all of them have used staggered valve timing to make the engines more efficient below VTEC. The additional motion runs a lot cleaner than opening both at the same time.
The only engines we build that don’t take advantage of this are the pure race engines.....and they have to idle at 2500rpm.
Bottom line is that for Street, and some track, VTEC lets you have your cake and eat it too...
I think on port-limited engines, the staggered valve events begin losing efficiency big-time around 4500rpm, so it’s not good for racing...."



So this engine has a cam that emphasis power down low which sounds logical since the cars that had these engines where all 5door/sedans civic /accord .
 
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