Forum » General Tuning Discussion » Rotary Injectior timing / Injectior angle tuning?

Rotary Injectior timing / Injectior angle tuning?

General Tuning Discussion

Discuss all things tuning in this section. News, products, problems and results. 

Page 1

Hey guys, I've done some research on the injectior timing but cannot find a true answer to my question.

I would like to know the correct way to set up the right injectior timing for our own particular rotary car.

I've seen people mentioning setting up 270 degrees BTDC(start of injection) from low load, then transition to 330 degrees BTDC toward redline.

I saw it in the Link G4+ software have selections for start of injection or end of injection, and wonder which would be best to use for setup.

This webinar helped a lot, and I would like to know does this technique also applies to a rotary engine?

My current tune is using the Link base map timing, 130degrees BTDC Start of injection throughout the rev range.

Many thanks :)

I tend to use end of injection for injector timing as you can directly relate that to intake valve closure (for a piston motor or the equivalent for a rotary) you will also find (well I have) most ECU's run on end of injection.

As you the actual timing itself, there is only one way really to find out and that is by testing and moving timing on the dyno and watching how the motor reacts. If it goes lean or rich, picks up torque or drops it and the biggest thing you will notice is throttle response.

You won't always find gains in any of these areas altering injection timing. The biggest thing which will decide this is obviously your injectors.

The larger the injectors (providing good quality operation) should net better results due to being open for a shorter amount of time during an engine cycle. If you have injectors which are too small and up around 80-90% duty cycle your injector is only closed for 10-20% of the cycle so you will find small gains from moving it around.

I tuned a Honda a few months ago which had the factory tiny injectors in it which were now maxed out (built higher powered NA) we swapped out to a set of ID1000 and picked up 5kw peak and 7-8 mid range due to now being able to alter the injector timing. This was in a car only putting out 160kw so not a bad gain.

Hi Chris

Thank you so much for explaining and the tips. I am currently using ID 2000s and ID 850s.

I have learned so much since I joined the community, I cannot thank you guys enough for this.

I will soon be able to put all these knowledge into practice in April.

Actually been pondering this question as I have just been tuning my FD3S too.

Haltech released a video a while back on rotary tuning tips ( where they recommend 270 degrees at cruise and 330 degrees at redline.

However, their Elite 1500 base maps have a very different setup - one that starts at 420 degrees and actually goes DOWN to 300 degrees.

Have been tuning on the street so far, so haven't really had a chance to check it properly on a dyno (I still have stock fuel system, so waiting until after I upgrade that before I hire one out). Would be very interested in what your results end up like!