20v 4age Silvertop – VVT pulley

Description

20v 4age Silvertop – VVT pulley

DISCONTINUED PART NOTICE & ALTERNATE OPTIONS

Unfortunately these Silvertop VVT pulleys are no longer available to buy genuine and we sold the last of our stock. Also there is no aftermarket alternative other than the VVT cancelling pulleys that remove the VVT function.

A Blacktop VVT pulley can’t be used with the Silvertop cams. It will physically fit but has a 5 degree difference in angle from the pin and hence the cam timing will be incorrect by 5 degrees.

However you can use the Blacktop pulley still if you fit the intake cam intended for a Blacktop, such as:

– A used OEM Blacktop intake cam

– Aftermarket cams that are proven to work with the original Blacktop pulleys, although the only type we know for sure will work are from Tomei and their “Poncams” – part number #143073. They can be purchased here:

Perfect Run- Tomei Poncams

– It’s been reported that it is possible to redrill the dowel locating hole on a Blacktop pulley such that it has the correct offset to suit a Silvertop. If such a modification was undertaken then the new hole would need to be placed such that the timing belt fits on the pulley one or more teeth offset from it’s original position. This is to give the new locating hole enough clearance so to not overlap with the original locating hole.

– Or one could just get rid of the VVT system altogether and run an adjustable cam pulley, this isn’t normally suggested as it will result in a large drop in the mid range power if standard or moderate profile cams are used.

Part information

It is common for the VVT pulleys on 20V engines to have completely failed or on the way out due to age and use. Sometimes it will be known with a loud ticking noise, but other times the only result is a loss of mid range power.

To test if the pulley is still healthy, the VVT solenoid can be unplugged without any risk of damage. This is located on the side of the cylinder head in front (left) of the header flange. When the engine is used without the VVT solenoid engaging there should be a considerable loss of mid range power. If there isn’t much change then the VVT pulley should be changed.

– More information on the VVT system can be read in this article: “Working with the VVT on a 4AGE 20V Engine”.