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  • pir4te ·
    Andrew

    If you are going to install VVT (phaser, timing case with solenoid and wire)...
    I have the earlier 156 core not the 189. I originally put 189 phaser on and a few problems arose due to the 10º difference. Man it just didn't fit!
    So the new cam phaser has 62º camshaft variance (the old cam phaser had 52º). Using the full 62º (retard) puts the cam in an unrealistic position and makes piston to valve clearance (at the full retard position) impossible.
    To cure this we fitted a Comp Cam phase limiter. Comp Cams make two versions and we tried both, ended up fitting phase limiter that allows 34º camshaft movement and still sufficient piston to valve clearance in all phaser locations.

    Dirk
    pir4te ·
    Andrew

    Sounds like you are not installing a cam phaser? In which case I should note the 105º centre line is way up there! Early Intake Valve Closing makes perfect sense idling to near torque peak (650 - 3800ish), like a truck, but about then compression duration becomes our enemy and you will want a longer expansion duration. Ideally the centre line should straighten here to its LSA (114º), then a few degrees of retard (depending on your events) increasing to plateau 3-13º retard around 6000 rpm. All adjusted in the tune, not by tackling the accessories drive, timing case, fluids, bolts, washers and gaskets.
    In answer to your question - yes all you require is the same TTY cam bolt to use the non-VVT stock sprocket, plus no need for an adjustable timing set you can install it at whatever degree you like, almost. No need for an adjuster unless you wish to make quick changes (there's an oxymoron!) without complete rigmarole of degreeing setup.

    Dirk
    GT Drew ·
    I have a question about VVT cams. I want to used Comp Cams VVT # 189-400-13 210/224 dur .556/.568 lift.
    Can they be used with the stock 1 bolt cam gear? I know there is an early and a late model variations. They vary by 13 deg.
    Or would I need a timing set like the Cloyes 9-3673TX9 with 9 key ways for 8 deg + or - adjustment


    Andrew
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