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@ Mark H. and anybody who might be interested,
Exhaust Cam
I already sayd in another thread 7A exhaust cam looks significantly more "high performance" minded than 3B/ABY/AAN and also of the ADU one.
And this couldn't be different because it cames off a NA engine wich needs much more "aggressive" timing for best possible VE.
Gains of using the 7A ex-cam on the turbocharged engine (knowing there still is no overlap, which we don't want on a forced induction engine) will probably be percentually less than the worstening of using the turbo cam on the NA engine, but it should anyway give some good gain in the mid to high rpm.
Intake Cam
Compared to the turbocharged ones:
Given I don't have lift among the other parameters (which might make some rilevant difference), timing is as follows (always according to data I have)
7A: opens 6° before TDC; closes 38° after BDC; duration = 224°
3B/ABY/AAN: opens 3° after TDC; closes 25° after BDC; duration = 202°
ADU: opens 13° after TDC; closes 35° after BDC; duration = 202°
1) All three of them (coupled with 7A exhaust cam) won't give overlap:
7A = -3°
3B/ABY/AAN = -12°
ADU = -22°
2) ADU one seems to me will give too much delay on intake valve opening;
3) 7A gives sensibly longer duration (while being a little "at the limit" with overlap) therefore giving higher flow gains (thus VE) expecially on high rpm.
"Reading" the timing from a theoretical point of view, since the use of the 7A exhaust cam already pushes VE optimization to higher rpm (together with rising stresses of valvetrain with higher lift) I would personally chose both intake and exhaust 7A cams.
Alternatively I think the 3B/ABY/AAN intake cam would be even better then the ADU one.
As I sayd many times, though, things on real life might change a bit, maybe due to not considering some other parameter right now.
So if anybody has something to say about this and/or has infos and feedback on weather using one option better than another and why, pleas tell.
Marco
Exhaust Cam
I already sayd in another thread 7A exhaust cam looks significantly more "high performance" minded than 3B/ABY/AAN and also of the ADU one.
And this couldn't be different because it cames off a NA engine wich needs much more "aggressive" timing for best possible VE.
Gains of using the 7A ex-cam on the turbocharged engine (knowing there still is no overlap, which we don't want on a forced induction engine) will probably be percentually less than the worstening of using the turbo cam on the NA engine, but it should anyway give some good gain in the mid to high rpm.
Intake Cam
Compared to the turbocharged ones:
Given I don't have lift among the other parameters (which might make some rilevant difference), timing is as follows (always according to data I have)
7A: opens 6° before TDC; closes 38° after BDC; duration = 224°
3B/ABY/AAN: opens 3° after TDC; closes 25° after BDC; duration = 202°
ADU: opens 13° after TDC; closes 35° after BDC; duration = 202°
1) All three of them (coupled with 7A exhaust cam) won't give overlap:
7A = -3°
3B/ABY/AAN = -12°
ADU = -22°
2) ADU one seems to me will give too much delay on intake valve opening;
3) 7A gives sensibly longer duration (while being a little "at the limit" with overlap) therefore giving higher flow gains (thus VE) expecially on high rpm.
"Reading" the timing from a theoretical point of view, since the use of the 7A exhaust cam already pushes VE optimization to higher rpm (together with rising stresses of valvetrain with higher lift) I would personally chose both intake and exhaust 7A cams.
Alternatively I think the 3B/ABY/AAN intake cam would be even better then the ADU one.
As I sayd many times, though, things on real life might change a bit, maybe due to not considering some other parameter right now.
So if anybody has something to say about this and/or has infos and feedback on weather using one option better than another and why, pleas tell.
Marco
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