Are cam lobes same, if camshafts duration and lift are same?

This came to my mind, are cam lobes actually same if cams duration and lift are same.
Or is there more "aggressive" lobes if duration and lift are same.

I mean that are some camshafts lobes more "round" than another cam which have same duration and lift.

Or does it depend at open dur BTDC and close dur ABDC in intake side and open dur BBDC and close dur ATDC in exhaust side???

To answer your questions, No.

Duration and lift can be seen as GPS coordinates to a location, there are many routes or paths to get there.

There are many lobe shapes that have the same lift and duration, with drastically different lift vs crank degree measurements.

Separate from lift and duration is the speed at which the valve is opened or closed.
The steepness of the ramp, in other words.

Also the lobe angle plays a part in the design. Two cams can have the same duration and lift but with different lobe angles they will perform differently.

nope, even with the same lift and duration specs camshafts can have greatly differing ramps. This is why there is always an "advertised duration" and then something like "duration @ .050"" measurement from any reputable cam manufacturer/distributor. The european companies will usually do a measurement of duration @ 1mm lift.

If you look at agap.se, they have cam lobes that are in the "street series" or "race series". The race series feature "faster" ramps, which gives you more area under the curve. The down side is that they are probably noisier, don't last as long, and harder on the valvetrain both in wear and maintenance. When Cam and I measured all the factory cams, and even some aftermarket ones, we found that pretty much across the board, cam lift at the fastest points was 10 crank degrees per 0.050" lift. If you could get that down to say, 9 degrees per 0.050", your cam could be at maximum lift for probably 10 degrees longer (5 up and 5 down) without changing the opening and closing points. It's the size of the lifter bucket, however, that determines the absolute fastest ramp you could theoretically have.

Does anybody have any examples of this, i need pictures of camshaft lobes at same duration and lift.
Has anyone a cam with 278 duration and 12mm lift, because one kind of lobe with this kind of cam looks like this:



Or do you have pictures to any camshaft lobes and put a specs to the picture so i can compare the lobes.

Are my camshaft lobe aggressive or mild, can you say it by picture which i posted.

The nose of that cam looks more aggressive than a factory piece. That's as much as I'd say.

Looking at lobes is really no way to pick a cam. The vibe of this thread makes me think that maybe you're restricted to these types of specs and you're looking for the greatest area under the curve? Give me some background to what your goal is and I may be able to help you understand a little better, but not as well as a real cam grinder could.

That base circle is small, for sure.
What you are looking for is a lift graph. If you plot the lift at short duration intervals, you see a shape.

Search for "cam lift graph" in google, then click "images".

I can't paste a decent example on this work computer, but you will get the idea from pics.

You need the fantastic rubber cam. The faster it spins the higher the lift and duration. I'm doing a run right now. Get them before they are gone!

dl242gt said:

You need the fantastic rubber cam. The faster it spins the higher the lift and duration. I'm doing a run right now. Get them before they are gone!

Click to expand...

Yeah, for sure!

I think we have a comic here!

dl242gt said:

You need the fantastic rubber cam. The faster it spins the higher the lift and duration. I'm doing a run right now. Get them before they are gone!

Click to expand...

You basically described a ?lofting? cam. No more duration, but a significant gain in lift and duration at higher lifts.

The 2ZZ-GE in my Toyota Matrix has variable valve timing and variable valve lift by means of an extra set of lobes on the cam shafts controlled by oil pressure and a solenoid.