NZ Performance Car - - Weekend Workshop -

First of all, some of you are prob­a­bly won­der­ing what a NEO VE head is, why it’s bet­ter than the DE/DET head, and if it’s any dif­fer­ent to Nis­san’s VCT (vari­able cam tim­ing) sys­tem.

Nis­san Ecol­ogy Ori­ented Vari­able Valve Lift, or NEO VVL, is a vari­able valve lift and tim­ing sys­tem de­signed by Nis­san as part of its an­swer to the for­ever-tight­en­ing emis­sions lim­i­ta­tions battle. The VVL sys­tem varies cam lift and du­ra­tion by use of hy­draulic pres­sure to switch be­tween two dif­fer­ent sets of camshaft lobes, one lobe suited for ef­fi­ciency, low-down torque and drive­abil­ity, and the other a much more ag­gres­sive cam suited to mak­ing power high in the rev range; some­thing which the VVL head has also been de­signed to cater for. All this ef­fi­ciency has its benefits in terms of air flow, as the VE head flows a great deal more air than the DE head, and as we all know, this is great for mak­ing power. Pro­ceed­ing with the VE head con­ver­sion elim­i­nates the VCT in your SR20DET en­gine, but that’s not a worry, as the benefits of VVL greatly out­weigh those of VCT. All this aside, one of the best parts about con­vert­ing to a VE head is mov­ing away from the float­ing rocker set-up that DE heads run, as th­ese are the weak­est link in a built SR20. The VE rock­ers pivot off a dowel and will never come adrift or break, mak­ing them much more re­li­able with big amounts of boost and high rpm use. Hans rec­om­mends a VE head to be used if the power lev­els re­quired or wanted are over 350kW.

NEO VVL vs DE Rocker

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