iridearocket

I'm new to the rotary engine, but the power curves as shown on dyno plots appear to be complete crap for our cars. I have no experience with my own car on a dyno, but looking at many dyno charts posed on another thread, it seems the power is very inconsistent. Not only does power make major dips, but it is also very unstable all the way up, especially in the power band of 7-9k revs. And when I drive, I can feel power kick in and out, especially when passing the 7k mark... you get a boost from behind.

As someone with enough of tuning experience on bikes, I can say that if my bike dyno looked like that, I would give up and buy another motorcycle before even bothering to try and smooth that out.

Is this normal for a rotary engine?

rotarygod

Normal for a rotary engine? No. Normal for a variable intake system that switches intake tuning as rpm rises? Yes. It's kind of like Vtec. You can feel when certain spots kick in. A lot of dyno charts look really bumpy just based on how much smoothing they had on the display. No engine is a smooth line revving up. If you see a dyno chart that is smooth like that, it was the dyno computer correcting everything with a smoothing factor.

With a new ecu such as the Interceptor, you can get more power and change the intake tuning switchover points to make more of a nice progressive powerband instead of one that just kicks in at a certain spot. This isn't hard to fix. It's actually quite easy. It's not an engine issue at all. As with most people that have problems with turbo kits, it's a tuning issue and not an engine issue.

The rotary is one of the smoothest most linear engines out there. I'd rather tune it properly to maximize what it is rather than get a new engine and hope that it's better. Tuning is easy.

iridearocket

So it's basically the car's intake system and ECU that put these lumps in the power curve? There must be some reason why Mazda opted for these lumps in power instead of smoother tuning, but it likely is not for performance reasons.

rotarygod

Unfortunately the tuning on the car is not optimal for what we'd like to see. Mazda has constantly changed flashes in order to preserve cat life. The usable powerband and it's smoothness have suffered from this. Just retune it and it's great.

iridearocket

Thanks!