According to redbook, standard one has 157kw and the xr6 has 172..

now im seriously considering doing a project converting a ef/el with a au motor..

being a project i would rather buy a standard motor and do head mods myself then buying a xr6 one for more $$

my question is, what has the xr6 got that makes more power?

thanks

cam and exaush valves i am pretty sure

The XR6 is 164kw and the VCT XR6 is 172kw

oh ok, should be simple enough to add those + more

whats a vct xr?

The VCT XR6 has variable cam timing, http://en.wikipedia.org/wiki/Variable_Cam_Timing, its surpose to have a better torque curve aswell. The VCT XR6 wasn't as quick as the normal 164kw XR6, because the VCT XR6 had IRS and had bit more weight.

vct = variable cam timing..

afaik the vct engine is in series 2 au xr6 and fairmont ghia..
and series 1 is pretty much the same as std au but has the tickford head and cam...
like the other xr's.

does anyone have or seen torque curve graphs of the vct and hp and std i6 motors.....be interesting to see the actual difference

VCT was avaliable in all the AU's from Series 1 to Series 3. I have one of the first AU XR6 VCT's, 1998 November build Series 1.

VCT had a different head, different cam and the VCT mechanism (build into the head). It also had factory fitted vernier gear (part of the mechanism) and a totally different ECU program. IRS was standard as was all power windows, power ariel and CD player. Exhaust from the cat back was a factory fitted 2" twin system (which was basically crap). Exhaust manifold to the cat was the same as HP XR6 (which was the same as the Forte).

As for the engine, it makes about the same power as the XR6HP when modded but is more fussy about exhaust and intake mods. Torque is generally a little better overall however not enough to counter the weight of the IRS and extra goodies.

Thats about all the obvious differences.