variable valve timing

[GrayZee]

I am wondering how the vct works in a z32. What controls when and under what conditions it turns on. Basically we have a AEM computer and were thinking of modifying the how it is controlled, is this possible?

[mtcookson]

I believe its simply an on/off switch. There's an actuator that pushes a "button" on the VTC assembly which allows oil pressure to build up and causes the timing change. Once off, oil flows through and timing changes back. Very simple.

[Ferd/289]

Here is an excellent url for Z32's// none better... but better use 'search'

http://www.twinturbo.net/

[BRAAP]

Here is an excellent url for Z32's// none better... but better use 'search'

http://www.twinturbo.net/

 

Good source of Z-32 info there no doubt, yet they have more than a few yahoos that are pretty closed minded and not afraid to let you know that.

[Challenger]

I dont know if you want to know actually how the VVT mechanisim works, but if you do go get the latest C&D and they have a write up on all the different ways VVT works.

[BRAAP]

Electrical diagrams for the factory service manual..

 

ECCS overall schematic;

 

http://www.300zx-twinturbo.com/cgi-bin/manual.cgi?list=efec&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=13&design=default&total=190

 

 

 

 

VTC tech info;

 

http://www.300zx-twinturbo.com/cgi-bin/manual.cgi?list=efec&dir=&config=&refresh=&slide=29&cycle=off&scale=0&design=default&total=190

 

 

 

 

When it is activated and not activated;

 

http://www.300zx-twinturbo.com/cgi-bin/manual.cgi?list=efec&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=30&design=default&total=190

 

 

 

 

Wiring diagram for the VTC circuits, relays etc;

 

http://www.300zx-twinturbo.com/cgi-bin/manual.cgi?list=efec&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=164&design=default&total=190

 

 

 

HybridZ member “booztd3” is also a great source of technical info…

[Guest Chrispy]

If tt.net aren't being helpful have a look at www.aus300zx.com. Much better group of people

[Sirk.240]

I was looking at this today on a z32 we are finishing up at the shop.

 

It's almost the same concept as V-tec. Except the cams run with it engaged using control oil pressure until like 5200 rpm to 6100 rpm? I may be off a few rpms but thats close.

They must of come up with this to get rid of a dead spot during testing, I don't understand why they wouldn't grind them the opposite and have them kick on for a 1000 rpms instead of off...

 

And I don't know why they wouldn't use the same concept on the exhaust cams instead of the intake cams so they could get some more exhaust flow at lower end. That'd probably be more beneficial.

[Guest Chrispy]

I wouldn't really compare it to VTEC as that uses a different cam profile for the high rev range.

 

I didn't think that it turned off until the revs reached 5200 again? I believe that they adjusted the intake to improve low end torque. Either way you woul achieve a little more overlap. Having the VVT on the exhaust could have stuffed up the crank angle sensor too. I'm sure nissan had a reason for doing it, just like AIV's