Curious as to why some of us have to wire the VDI and aux ports open when everthing is working like it should. I mean it's bad enough to wire the aux ports open, killing a bit of low end, then we wire the VDI open, which takes a furthur low end hit. And yet some claim it's more than made up for in the top end, as if we gain even more top end from wiring it open than if the system was working properly to begin with. I don't think junking the parastic airpump makes up for the loss in low end either.

 

DING DING DING!!!!

Give the man a cigar!

That's the first sensible thing I've heard anyone besides me say about these things in over a week. It seems inconceivable that, assuming the system is working as it should, the engine would make more by locking the valves in one position or the other. Mazda designed them that way for a reason.

I think the reason most people wire them open is because the stock system stopped working. Unfortunately, this seems to be the case with far too many of them. I think it's mostly due to lack of use, either from previous or current owners. You know, oil, carbon, and gunk get caked in the passages and keep the valves from turning as they should. I think if you take the car and redline it every now and then, these things would work as they should.

Now one thing that does make sense to me is making an insert in the sixport valves to allow for improved (less turbulent) flow. These things have horrendously poor flow design. I can definitely see where inserting a flow director would help power. Not incredibly, but a little anyway.

Ren

 

And wouldn't it be better if the VDI opens up the same time as the aux ports at 3500rpm? I mean 5500rpm is kinda late for top end pull.

 

The VDI is tuned perfectly in both ranges. opening it lower would hurt midrange. I notice no real low end gain, but great midrange up to about 5500 when set to low, in high, midrange is down a tad, but it really gives a kick at 6000 when the intake pressure wave begin oscillating in the right frequency for the longer (or shorter... crap.. tired...)intake tract setting.
I can give first hand attributation to removing all the A/P related stuff. My low end torque is pretty much the same as when my car was bone stock, but my high end now with everything is crazy. I lose traction after 6000 in first gear with 225's!
Most people wire open the 6p's becuase they suspect whether they are opening or not.... Usually they ARE openeing but they just think their car should be faster.. and blame the 6p's Removing the sleeves is better than wiring them open, but ONLY if your engine is heavily modified, and flowing MUCH more air than stock. Don't bother is you don't have a ton of mods, and maybe porting.
As for wiring open the VDI, well, I prefer electrical actuation. Just rig a relay to the signal the ECU sends out at 5500 rpms, and mount a power lock solenoid to the VDI linkage.

 

Dyno results before and after wiring 6ports open?

Forgive my skepticism, but it just doesn't make good sense to me.

Ren

 

Alot of us here think that way too, but we tend to get drowned out by the louder voices of those who think that by wiring everything to max is gonna make more power. What is most important is power across the board and where you can use it. Even if it has, say, 2 more HP wired open at 7K how often are you at 7000 rpm? When its time to shift, thats when. And then you are stuck with 5 HP less at 3500rpm when you are accelerating or out of a turn.
Some see the wiring/removing as a cheap way to add horsepower and they often don't have a good understanding of usable power.

Thanks alot by the way I've been arguing this until I'm blue in the face, nice to see someone thinks like I do

 

i believe the same, i know a working system works amazingly better than a wired open system, i mean i ran a 14.4 in the car that had a working system in it, so it cant be that bad, i have wired open or removed the ones i have now because they were completely frozen shut. the pineapple racing 6 port sleeves look amazing, look perfect for flow in there. and you cant have the VDI open at the same time as the ports because it KILLS mid range power, thats why it opens at 5000rpm.

 

It kills me that some people think they know more about these engines than the people who designed and built them

You need at least a simple understanding of port timing and the cycle of the rotary in order to understand why you will definately lose low-end. And I don't pretend to fully understand the VDI, other than its a pretty ingenous system and must work pretty damn well because I feel it could feel it come on stronger than the aux. ports (I don't have my FC anymore now I'm back in 4-port land).

I can see how an engine with internal mods might run better at high speeds, maybe better enough to make up for the losses down low. That would also depend heavily on what you want out the car and makes the whole debate very subjective.

 

Hey now guys....who was one of the very first on this forum to have the Pineapple sleeves?? To be honest, i wish i could open my vdi a bit earlier. It may be because of my mods, but when the vdi hits at 5.5k, it realy comes alive. I would'nt mind having it open at like maybe 5k for me, or maybe a little under 5k. I wish someone would make something that would allow an adjustable opening for the vdi. Ohh....and it would have to be adjustable from the cockpit. For ohhh...say $40, including shipping and handeling. Is that asking to much? CJ

 

Listen to all the people how say don't open the VDI sooner, including me!!
I speak from experience- the ultimate knowledge.
My car is the same way, it really jumps at 5500 rpms. But the vdi opens at 5200 though!!
The power increase isn't from the VDI opening, it's from the reversion waves from the intact tracts reaching the prefect frequency to pressurize the intake charge. With the VDI in high postion (5200 rpms)It reaches this synchronization at about 5500 rpms.



If you don't believe me, then pop your actuator off your VDI and LEAVE
high- you'll see what happens. You car will still perform exactly the same above 5200 rpms, but will lose some midrange.

 

WORD Up People, I have actually taken my emissions off and put them back on cause I noticed a large lack of power, I got beat by a beretta for christ's sake! finally some people that believe me on this forum