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Discussion Starter #1
I was just wondering if anyone had complete camshaft specifications for the Busso engine? I am looking for consistent details like lift, duration and lobe separation angles, preferably at either lash point or at 1mm lift.

It would be great if we could perhaps compare stock 3.0 V6 cams with GTA cams for example, as the GTA cams have different timing settings as well as differences in lift and duration.

Thanks!
 

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Discussion Starter #3 (Edited)
Thanks alterro. Really valuable information. I have been told that on the 3.2 engines, the lobe centers are also different because the either exhaust cam timing, or both, have also been altered. can anyone perhaps confirm or deny this?

So far we have:
3.0 V6
Cam Lift Duration Open Close Lobe Center
Inlet 9.3mm 215 1 BTDC 32 ABDC 109
Exhaust 9.3mm 215 37 BBDC 2 ATDC 109

3.2 V6 GTA
Inlet 9.3mm 223 1 ATDC 44 ABDC 113
Exhaust 9.3mm 215 36 BBDC 3 ATDC 110

3.2 V6 GTA2 (Popular grind in South Africa)
Inlet 9.3mm 231 9 BTDC??? 40 ABDC??? 109???
Exhaust 9.3mm 223 41 BBDC??? 6 ATDC??? 109???

The GTA2 grind adds another 8 degrees duration to the inlet cam and uses the GTA inlet cam profile on the exhaust. It pumps the power of a 3.2 engine to 196kW (263bhp), and if induction, exhaust and mapping is done, then this potentially climbs to 215kW (288bhp). I have seen a few cars with this kind of power, but they had carbon plenums and F430 throttle bodies as well.

My next question: Does one have to replace the plenum and throttle body to get this kind of power or will the stock units be sufficient? I would like my engine to look as stock as possible.
 

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It should be like that:

2.5/3.0 V6
Cam Lift Duration Open Close Lobe Center
Inlet 9.3mm 215 (180-1+36) 1 ATDC 36 ABDC 109
Exhaust 9.3mm 215 (180-2+37) 37 BBDC 2 BTDC 109

3.2 V6 GTA
Inlet 9.3mm 223 (180-1+44) 1 ATDC 44 ABDC 113
Exhaust 9.3mm 215 (180-1+36) 36 BBDC 1 BTDC 109
 

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It should be like that:

2.5/3.0 V6
Cam Lift Duration Open Close Lobe Center
Inlet 9.3mm 215 (180-1+36) 1 ATDC 36 ABDC 109
Exhaust 9.3mm 215 (180-2+37) 37 BBDC 2 BTDC 109

3.2 V6 GTA
Inlet 9.3mm 223 (180-1+44) 1 ATDC 44 ABDC 113
Exhaust 9.3mm 215 (180-1+36) 36 BBDC 1 BTDC 109
That duration is at 1mm right?
 

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Thanks alterro. Really valuable information. I have been told that on the 3.2 engines, the lobe centers are also different because the either exhaust cam timing, or both, have also been altered. can anyone perhaps confirm or deny this?

So far we have:
3.0 V6
Cam Lift Duration Open Close Lobe Center
Inlet 9.3mm 215 1 BTDC 32 ABDC 109
Exhaust 9.3mm 215 37 BBDC 2 ATDC 109

3.2 V6 GTA
Inlet 9.3mm 223 1 ATDC 44 ABDC 113
Exhaust 9.3mm 215 36 BBDC 3 ATDC 110

3.2 V6 GTA2 (Popular grind in South Africa)
Inlet 9.3mm 231 9 BTDC??? 40 ABDC??? 109???
Exhaust 9.3mm 223 41 BBDC??? 6 ATDC??? 109???

The GTA2 grind adds another 8 degrees duration to the inlet cam and uses the GTA inlet cam profile on the exhaust. It pumps the power of a 3.2 engine to 196kW (263bhp), and if induction, exhaust and mapping is done, then this potentially climbs to 215kW (288bhp). I have seen a few cars with this kind of power, but they had carbon plenums and F430 throttle bodies as well.

My next question: Does one have to replace the plenum and throttle body to get this kind of power or will the stock units be sufficient? I would like my engine to look as stock as possible.
That duration is at 1mm right?
Right.
 

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Ill stand corrected if wrong but im fairly sure 2.5 & 3.0 are 9.3/9.3 & Gta are 9.7/9.3
This is why Jim k can do a bigger lift on the Gta cams then on the 2.5 & 3.0
 

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Ill stand corrected if wrong but im fairly sure 2.5 & 3.0 are 9.3/9.3 & Gta are 9.7/9.3
This is why Jim k can do a bigger lift on the Gta cams then on the 2.5 & 3.0
No, all V6's intake cam's lift is 9.3mm. This is what the manual (E-learn) says and this is what I've measured when I got both cams, from 2.5 and GTA, in my hands. GTA's cams have a flat top which is, from what I've been told, quite unusual. Their profile is 2.5/3.0's alike, but it looks like the peak was stretched by 8 degrees.
 

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I stand corrected just goes to show your never too old to learn :thumbup:
 
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