Vtec Tuning

For this example I am using two h22 motors. Both of them are stock and have pretty much the same exact mods besides one having a skunk2 intake manifold and one having a EuroR intake manifold.

I found it pretty interesting when I did a cold air intake test versus a modified stock short ram intake. This graph shows a change in a fully tuned motor. On the last run I decided to put my 3" cold air/BPi flowstack on his car and just see what happened. The results were very intriguing.

Peak power did not increase much but look at ~4000 rpm!!

I had the vtec crossover for this motor at 5000 rpm. Hmmmm, what happens if you start lowering the vtec crossover towards that peak at 4000?

Well here you go:

This is the other motor. The one with the Skunk2 manifold but with my 3" cold air/BPi flowstack.

on the runs showed here, you can see the progression of the vtec crossover. Gaining more and more midrange.

So in this aspect, the intake you decide to run for your car will dramatically change where the vtec crossover needs to be. And that my friends requires tuning.

Get your damn cars tuned you filthy animals!!

UPDATE

i did this test recently with my h23vtec and here are the results.