On the stock turbo with stock cams, I usually see power lost with any mivec from 6000/6500+

- Bryan

 

no clue what any of that all means, but its very kind of you to share all this for the others!

 

So you just taper off both cams usually...

As in 6000 set intake cam to 10 and set the exhaust retard to 0 ?

I have been seeing that in VDR I get gains with setting the 6000 area up to -10 retard and taper off the intake came a lot. I know VDR is not a real dyno. But best measure for us regular joe's.

 

you guys are probably requesting the same amount of overlap anyways.. 0* exhaust + 10* intake = -10* exhaust + 0* intake

obviously that doesn't necessarily mean the same power...

 

Yeah, exactly... now which was is the right way... LOL

 

well do you want to try changing 6000+ in the following configurations:

intake = 10*
exhaust = 0*

intake = 0*
exhaust = -10*

intake = 5*
exhaust = -5*

then see what produces more power in VDR?

 

Yeah, will have to test this out...

 

I thought going less then 10 on intake did nothing?

- Bryan

 

no idea..

Clipse3GT - when you do those tests make sure you log Actual Intake + Exhaust cam position as well

 

From looking at my logs... I seen that the Actual Mivec Intake will dip below 10* timing...

I will do some testing when weather is nice... back to back. Try all three maps starting at 6000, no other changes to the map.

 

Yeah, you shouldn't be able to go below 10* on intake (actual log maybe around 8* or so). You can actually check this at idle, just throw in a map with 0* intake and you'll see the actual is no different than as setting it as 10*.

 

Maybe a little slop can buy you a couple degrees?

 

So what is the difference between the GST and the Hiboost map? They look pretty different. In what ways do the underlying philosophies differ? Which has better spoolup? Top power? Fuel Use? . . .

I wish I could learn more about Mivec, but I'm already teaching myself a lot right now (3-port, coilover setup from corner-weights to rideheight, bound and rebound, vehicle dynamics) so I can't take on another topic right now, especially one as complex as Mivec...

 

When I originally created these it was for the Stock Turbo, and I was relatively mild in my changes. The basic idea was to take the max values from the JDM and US maps and make it smoother transitions without going more than about 10* different from stock if I could help it.

Fast forward to more recent testing and I've seen spool gains by going to 30-35* intake advance down low, and discovered that too much exhaust retard with certain exhaust manifold and turbo combos can drop power. Really for best results you need a dyno so that you can test the different combos back to back, only make 2.5* pr 5* changes each time and adjust just the intanke or just the exhaust side and go with what makes the best spool and power.

One thing to note is that rapid changes in mivec timing tends to never happen as the system can only respond so fast to inputs. Using Interpolate beteen the cells on the maps can smooth things out a bit which is one reason that the GST map looks so different. Also the 2011 Mivec maps are quite a bit different and I've since adjusted what I'm using based on those so I'll upload the changes since last year.

 

Thanks! That would be much appreciated!

Also thanks for description! Learned something new again!