Im going to remove the 6pi system on my s5 na. I already have the exten manifold off, and i was wondering if i should remove the VDI as well as the actuators and the sleeves?

 

bump tump

 

ill just leave the VDI in. After reading the FSM some, it doesnt look like any good can ceom from removing it
correct me if im wrong.

 

Leave the VDI in! Wow! Do NOT pull out the VDI.

If you want to remove the 'six' (aux) ports, I suggest pulling off the lower manifold and pulling out the rods, sleaves, and acutators. Then knock out the little brass inserts.

Tap the hole left over and drive a bolt into it. Then sand the bolt down.

 

lol, i suck at cars and the web.

 

Nah, you're doing great, your car still runs, right?

And the web? You're actually using punctuation, and from the posts of yours I've seen, you dont randomly explode into a flaming ball of hate spewing out endless droves of misinformaition. . . like some people . . . yeh . . .

So, thats a plus!

 

Lol, thanks,

 

I've been asked in a PM to explain my reasoning behind the VDI, so here is a very bastardized explination.

The aux ports and the VDI are both there to broden the torque curve.

The VDI (Variable Dynamic Intake) works by 'changing' the intake runner's size to become 'shorter' at very high RPM. (If you don't know how that actually works, I can explain that). The runners on the RX-7 are very, very long in comparison to most cars. The reason is to help with low end torque. Long runners are better for low end, and short(er) ones are better for high end.

The VDI cylender, if removed entirely, will leave a very very bad area for flow inside the chamber.

The aux ports work in a different way, they effectively 'advance the cam timing' of a rotary engine, as the port is farther into the intake 'stroke' (Kind of like a higher lift valve on a piston engine)

Dyno numbers report that your results are not typical at all. On modified cars, people dyno them with either of the ports completely open, then completely closed, then they tune them to open at the given RPM where the line intercects.

I personally noticed a 1-2MPG gain on the highway, along with some part-throttle torque, when I forced my then stuck ports open ports to the closed position. I have since repaired the whole system on my car.

If you want to remove both of those systems, I reccomend just replacing the whole intake with one that is shorter and less convoluted, you will notice a bigger gain in high end without much more loss in low end.

If I'm wrong, somone please correct me, but this is a simpler version of my understanding of the two systems.

 

Nice post! Thanks

 

I was responding to a PM originally, thats why that line is in there. :O

Sorry about that, just ignore it :-p