Adjustable Cam Gears and VTC.

[jaffaZ32]

I've just bought a set of Tomie Adjustable cam gears and after opening the box realised that they look totally different to stock e.g. where is the VTC???

 

After googling Adjustable cam gears ditch the VTC.

 

My inistial throught ditching the VTC would result in a slower Zed?

 

but correct me if i'm wrong, does VTC just advance and delay the timing? but with adjustable cam gears i could have the VTC timing on all the time? as i would advance or delay the cam gear so it was fixed?

 

If that is the case then why do we have VTC and why don't cars run with the VTC timing all the time?

 

Or have i completely got the wrong end of the stick altogether?

 

Can someone explain how this works and if it's best to have adjustable cams or VTC?

[jaffa]

VTC is variable, so gives extra torque up to approx 5000 rpm, then switches off.

adjustable gears mean you can tune for max torque higher or lower down the rev range, not both.

 

Adjustables are a compromise, higher peak numbers (if that's what you tune for) but less flexibility

[jaffaZ32]

Oh right, so in a sence the VTC is better all round?

 

I guess the adjustable cam gear would advance or delay the timing more than the VTC but doing so you would loose either low end or high end power as where with VTC you would have best of both as it would adjust so you had both.

 

I did order a full set of adjustable gears, am i correct in saying the VTC is only on the inlets cams? So i could run adjustables on the EX cams to dial it in perfecticly and Stick with VTC on the inlet cams.

 

I also found this picture from Tomei to show what your saying.

 

Thanks for your info.