Apexi help on a Gen3

[BlitzBoy]

Nobody with highpower Rotaries tunes with Detcans its not like a piston engine, any real knock or in your word "tinkle" will blow the engine straight away you dont get a second chance hence why nobody tunes with detcans

[Scott.T]

I assume they have a Knock Sensor as standard.
If that\'s the case and what your saying is true, then whats the point of having one.

How do you manage to tune for optimum timing, there must be a rule of thumb EGT value to aim for then ??

[RobEVo5]

Got wideband plumbed into day and using the logworks software which is great. Looks like my suspicions were correct and running very rich across the range.

Tickover was about 11, mid range 12, and top 10\'s.

I ran out of time earlier after intially just playing with tickover before I took it for a run. Earlier I was just trying to get the tickover to 14.7  but was proving difficult. As soon as I get past the low 13\'s the idle starts to get slightly lumpy. Pretty sure its running standard injectors....... any thing else I can tweak or change to help in the idle area

Will try pulling back the injector duty which should hopefully balance the complete map, but don\'t think this enable me to get an 14.7.

Any pointers ?

Noticed car is only pulling 0.64 boost as well. but will leave that alone until I can get the fueling sorted. Good news is its running very rich and underboosting, yet still feels VERY quick. So very exited at the prospect of getting it sorted.

[BlitzBoy]

I assume they have a Knock Sensor as standard.
If that\'s the case and what your saying is true, then whats the point of having one.

How do you manage to tune for optimum timing, there must be a rule of thumb EGT value to aim for then ??

The knock sensor on standard twins non modified RX is used as warning and nothing else when it senses a certain level of noise it pulls back the timing and boost on a "standard ecu" as there is no extra noise from a modfied exhaust to interfere with it etc etc. On an Apexi issue it will not retard the ignition it will just flash the heat light

Yes there is  optium timing for different levels of tune and porting, also optimum EGTs as well as afrs, there is certain figures to shoot for with and without WI, but im not going to tell all my secrets but u can do a search and find nominal safe values

[BlitzBoy]

Got wideband plumbed into day and using the logworks software which is great. Looks like my suspicions were correct and running very rich across the range.

Tickover was about 11, mid range 12, and top 10\'s.

I ran out of time earlier after intially just playing with tickover before I took it for a run. Earlier I was just trying to get the tickover to 14.7  but was proving difficult. As soon as I get past the low 13\'s the idle starts to get slightly lumpy. Pretty sure its running standard injectors....... any thing else I can tweak or change to help in the idle area

Will try pulling back the injector duty which should hopefully balance the complete map, but don\'t think this enable me to get an 14.7.

Any pointers ?

Noticed car is only pulling 0.64 boost as well. but will leave that alone until I can get the fueling sorted. Good news is its running very rich and underboosting, yet still feels VERY quick. So very exited at the prospect of getting it sorted.

Tickover is rich, aim for about 13-13.5 afr if you go towards 14.7 it will get lumpy and wont idle well. I am assuming when u say pulling back injector duty you are talking about changing the fuel correction cells? if you are messing about in a different section of the commander menu STOP!

[RobEVo5]

Tickover is rich, aim for about 13-13.5 afr if you go towards 14.7 it will get lumpy and wont idle well. I am assuming when u say pulling back injector duty you are talking about changing the fuel correction cells? if you are messing about in a different section of the commander menu STOP!

Thats good new then in a way as I can get 13-13.5 no problem with a smooth idle. But was targeting 14.7 in consideration of when it comes to MOT time and what should be the optimum. Oh well might just have to find myself a kind MOT station when the time comes.

With regards to the fuel - Yes was initially adjusting the fuel cells in the map, but once I noticed it was rich across the entire fuel map. I thought about going to the primary and secondary injector duty section to change the value from 100% to less, much the same as you would if you put in larger injectors.

I figured this would be a quicker way of leaning across the range rather than decreasing what would likely need to be every fuel cell value.

[Scott.T]

The knock sensor on standard twins non modified RX is used as warning and nothing else when it senses a certain level of noise it pulls back the timing and boost on a "standard ecu" as there is no extra noise from a modfied exhaust to interfere with it etc etc. On an Apexi issue it will not retard the ignition it will just flash the heat light

Yes there is  optium timing for different levels of tune and porting, also optimum EGTs as well as afrs, there is certain figures to shoot for with and without WI, but im not going to tell all my secrets but u can do a search and find nominal safe values

Thanks for the info, but I am well aware of the Knock correction ability of a Standard ECU and lack of it in an Apexi, as I run one in my own car (not a RX7).

How do RX7\'s manage to get through the MOT (incl. CAT test for Post 93) if they idle at 13.5AFR I would of thought that would be certain to fail.

I have found posts regarding AFR and cruise at 14-14.5 seems to be mentioned, but from what you say, not at idle.

[Scott.T]

Here you go Rob, some quotes from other sites :

Quote :"rotaries do not like to idle under 12.6AFR, you are misunderstanding stochiometric values, those are based mainly on piston engines and for cruising light load applications.

with a good catalytic converter and airpump blowing on it then toss AFR values out the window, lean it out til it just starts to want to hunt/misfire/die at idle then richen it up a tad and that should be good for emissions testing basis."

Quote :Leaning out too far in vacuum will just cause stuttering and rougness. Going much leaner than stoich may start to make your emissions worse. It\'s kind of a shot in the dark without a wideband O2.

Here is some info by Chuck and Kyle (PFC tuning GURUs) about how lean you can go...

In previous posts this year, Kyle and I have mentioned about adjusting transistion areas. In fact if you were to read all of our posts, you would have volume two and know all we know.

(1) cruise should be set for best smoothness plus mileage. This is P5 to P6 normally. Set high 15AFRs to low 16AFRs.

(2) P10 is 0 vacuum/boost, go for 14.7AFR, stoich.

(3) For P7 - P9, taper between (1) value and 14.7AFR, or set all the same as cruise. If you look at your boost gauge, when you floor the throttle from cruise, your boost gauge goes instantly from vacuum to 0 + boost, So in reality, P7 - P9
are useless unless you find a place where you can cruise at 100+ mph. Yes in Germany you would use these.

(4) Your P16 and P17 are way too rich. Go about 11.5AFR for P17 if you have a large IC.

(5) For P11 - P16 taper the AFR from 14.7 to 11.5AFRs. I\'ll do these using simple logic. Since stoich (14.7) is about ideal for normal driving and power, we will set 0psi at that then richen up linerally until we hit our first tuned boost area of P17.
P10 14.7
P11 14.5
P12 14.0
P13 13.5
P14 13.0
P15 12.5
P16 12.0
P17 11.5

(6) idle ~14 AFR

Unless you can afford to dyno power tune all P rows, this is your best bet.

[RobEVo5]

Cheers M8, so looks like perhaps 13-13.5 afr on idle is ok then on a rotary (bloody odd engines these and not like a piston engine at al). I am getting stoich on cruise, its just the idle.

nothing like old school methods, but its now been taken from 11\'s on idle to 13\'s on idle, which has made the difference between it stinking of petrol on idle to more like what I would expect. If I had taken the plugs out before and after I bet I would have noticed a difference as well.