Cams move slightly with Cam Locks on - Page 2 - Alfa Romeo Forum
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(Post Link) post #26 of 29 Old 14-09-12 Thread Starter
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Ha, if only I'd have had that information 5 hours ago, lol. 2 snapped bolts and a trip to Screwfix later the new bolts are now done up to 12nm.

It's all back together and running fine now, thanks for the tools Chris!
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Originally Posted by scottyf View Post
Sorry I didnt explain myself correctly.

I understand cam timing is important when timed with TDC. However providing that duration is the same you can advance / retard the cam timing to suit at TDC by varying degree's by using the TDC guage. This then changes where power is made and at what rpm. However its kind of made redundent by the fact most systems use some kind of phase variator like in alfa engines to change that over lap.

Changing the ignition timing to a point the ECU will control with the map. But you can play with the overlap yourself to get a slightly higher power later on in the rev range. But its at a cost of a smooth idle and lower power.
Well done to the OP for getting it all together !
some interesting data on the catcams site CATCAMS Introduction page: the pearly gates to engine power!
The VANOS (VVT) system on the intake camshaft changes the PD from 117 to 92.
inlet timing with full retard (variator disengaged below 3000rpm) is -9/44 so when variator engages the inlet timing would become 16/19. Very early inlet closing as a result. I am not sure but I wonder does the variator disengage at higher RPM?
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(Post Link) post #28 of 29 Old 15-09-12 Thread Starter
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It does sound a bit whiny now, which I'm pretty sure wasn't there before. I'll take a video and post it up
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It does disengage. At idle I think it's disengaged up to about 1200rpm. Engages up to 3000 rpm then disengages again.
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cam , cams , locks , move , slightly

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