is it possible to get linear power band with oem sequential turbo? meaning, not having the dip for the secondary turbo transition. i'm not planning to make big power or anything, 350hp should be more than enough for me. i just hate the transition feel at the track, it reminds me of the v-tec dip for hondas. any help would be great.

thanks

 

The powerband will never be linear while being sequential. You will always have a huge surge of power and torque at the transition regardless of whether it dips a couple psi or not.

You can dial out some of the dip and have a pretty hard hit at the transition. One of my FD's had almost no dip and it was probably the funnest car I've ever driven. But it is still not what you are looking for. It makes it even more difficult to drive at track days (if thats the kind of track you are referring to).

 

stock oem old solenoids together with higher boost can be abit sluggish if everything isnt working properly. a worn solenoid, a small leak, a wg/turbocontrol arm etc. that is moving slowly... lots of things that can create this feeling.
Also, the stock solenoids are rated at what? 15 psi?

making sure everything mechanical that moves, is moving properly, making sure there are no leaks, getting for ex. the aezknightz 100psi industrial solenoid kit for awesome solenoids, and fiddling with set and gain on a good electronic boostcontroller, can pull out some of the dip. but, the dip will allways be there.
I kind of like the dip though, as it pulls hard on primary, then a slight backing off, then a kick in the rear and off we go again to 9K.
Besides, racing it you will rarely dip under 4,5K anyways. If so, you should take a look at your gearing selection and brak-in before turn-in.

 

If you have a PowerFC and a Datalogit, yes, it's totally possible.

My car is sequential with an aftermarket boost controller (AVC-R) and a PowerFC. By playing with the RPM for the sequential crossover (lowered it a bit) I was able to almost totally dial out the transition flat spot. It just goes nice and smooth.

I think Mazda actually engineered in the transition dip as a marketing thing. When you test drive the car, you feel that second turbo come on, and go "boy, this twin turbo thing is neat!" I don't really think there's any engineering reason they couldn't have eliminated that dip.

Dale

 

thanks for the replies. this is very helpful to make my decision. but Like Dale said, i totally agree with you with mazda using the transition dip as marketing. Its basically like honda putting the dip for the v-tec. It does feel good if it's just a street car, but on the track i personally don't like it.