HKS Vcam Before and After on R32

[TXSquirrel]

My tuner just did some before and after pulls with HKS Vcam and shared on his Facebook.  I would like to share that here for those thinking about Vcam.

His car is still running on stock R32 turbos with steel turbine wheels.  The pulls were done on E60 ethanol mix.

https://www.facebook.com/houston.zauto/posts/1368728369930762

 

Edited October 18, 2018 by TXSquirrel

[reaper]

Well worth doing

[r32-25t]

Especially when you run it through the ecu instead of the silly box hks supply 

[TXSquirrel]

I extracted more info out of him, really hope he doesn't mind me posting this.  RPM across the top and load on the left.

Question for you folks about how camshaft degree translates into cam gear degree.  His HKS exhaust camshaft has a centerline of 110, and he gained across all RPM range by retarding his exhaust cam gear by 2 degrees.  My Tomei has a centerline of 115, to get the same effect how should I adjust my cam gear?

[JGTC]

Good info, thanks for posting, we rarely get a chance to look at back to back data.

[r32-25t]

that is a difference with vcam turned on and off my car, this is a very conservative 98 tune before we swapped to e85

[TXSquirrel]

Yeah the difference from 3000 to 5000 rpm is astonishing.  My tuner made his pulls on stock R32 turbos, so with any decent aftermarket turbos the improvement should be more pronounced.  He has actually pushed hard on those stock turbos and intends to blow them up as he has a pair of 2530 waiting to go on, but they are surprisingly tough.

[sneakey pete]

When you say on vs off, do you mean activated vs not activated? or optimal vs sitting at base conditions?

Its still a slightly misleading comparison as your off isn't going to be as optimized as a normal dumb cam. 
Still, I wants it.

 

[r32-25t]

It’s off as in sitting solid at zero, so it’s the difference between having vct and static camshaft. mine is controlled through the haltech 

[r32-25t]

Just for reference mines the baby one with with 248° cam and only 30° of variation 

[whatsisname]

On ‎10‎/‎26‎/‎2018 at 1:26 PM, r32-25t said:

that is a difference with vcam turned on and off my car, this is a very conservative 98 tune before we swapped to e85

But look at all that top end power it lost! That 1.5kW is a huge price to pay...    

[r32-25t]

Yep we were devastated lol

[GTSBoy]

On 10/25/2018 at 11:55 PM, TXSquirrel said:

Question for you folks about how camshaft degree translates into cam gear degree.  His HKS exhaust camshaft has a centerline of 110, and he gained across all RPM range by retarding his exhaust cam gear by 2 degrees.  My Tomei has a centerline of 115, to get the same effect how should I adjust my cam gear?

Camshaft and gear degrees are identical.  2° is 2°.

That may not answer your question.  And the lesson learned by retarding the HKS cam by 2° may not be applicable to your cam.  Those sorts of changes really come down to what effect the change has on the overlap of the in and ex lobes.  As your centrelines are so different, then it is quite likely that the overall profiles of your cams are quite different and you may end up with a different result.  You might need more retard, or possibly less, or possibly gain from a little advance.