VCT/OCV questions

[arronm]

Brad not telling ALL the truth.

 

Dual Independent Variable Cam Timing (DI-VCT)

The Barra 195 engine had a vane-type VCT phaser – produced by Aisin – on each camshaft that provided continual variable adjustment within a 60 degree range (10 degrees advanced or 50 degrees retarded from the initial pin lock position). Each camshaft phaser was hydraulically controlled via an oil control valve that was mounted on top of it.

The variable cam timing system for the Barra 195 engine was Ford’s ‘Dual Independent Phase Shifting’ (DIPS) which enabled the intake and exhaust camshafts to be varied independently of each other. In contrast, the Barra 182 engine had Dual Equal Phase Shifting (DEPS) in which the intake and exhaust camshafts could only be advanced or retarded by the same degree synchronously such that valve overlap was a constant 25 degrees.

Valve timing for the Barra 195 engine is understood to be the same as the Barra 190 engine and is given in the tables below. From these, valve overlap could be varied from -35 degrees to 85 degrees, intake duration was 256 degrees and exhaust duration was 256 degrees. Furthermore,

• On low throttle openings, timing would be retarded by up to 50 degrees to improve fuel economy;
• At idle, the intake camshaft was retarded by 18 degrees for improved combustion and a stable idle; and,
• At higher loads, timing would be advanced for greater power.

 

 

Barra 195 engine - valve timing: pin lock position Intake Open 27.5° BTDC Close 48.5° ABDC Exhaust Open 78.5° BBDC Close 2.5° BTDC

Barra 195 engine - valve timing: 10 degrees advanced Intake Open 37.5° BTDC Close 38.5° ABDC Exhaust Open 88.5° BBDC Close 12.5° BTDC

Barra 195 engine - valve timing: 50 degrees retarded Intake Open 22.5° ATDC Close 98.5° ABDC Exhaust Open 28.5° BBDC Close 47.5° ATDC

Edited 10/12/17 01:50 PM by arronm

[XR6TTUB]

Ahhh bugger

 

So this isn't contributing to my stupid idle'

 

Keep digging I guess

[arronm]

Are you sure the inlet gasket manifold isnt leaking???

[XR6TTUB]

Nope, intake manifold gaskets are all new and tested no vacuum leaks

 

the only thing I’ve got my fingers pointing at atm is the pcm/tune

looks like someone has played or tampered with the tune to make it more fuel efficient as timing is pulled quite a fair bit