Enthalpy ECU and 20 degree timing

[jacobzking]

I have a basic concept of ignition timing but that's the end of it. I'm ordering an Enthalpy ECU and have been instructed to set my timing to 20 degrees to correspond with their ECU settings.

Why the 20 degrees and not 13-15 like the FSM says? I've only heard good things about the Enthalpy tunes, so I'm not worried; just curious.

Also, what effect would it have if I ran the normal 15 degrees?

Thanks

PS: my setup is blacktop S13, s15 t28bb, 555s, z32, metal hg and bpu. Car is pretty much just a track day car.

[snafupossum]

The tunes are setup to be extremely safe base type tunes. This is done because there is not a certain formula to what each motor can do with the mods given so extra precautions are taken(runs a little rich, backed off timing) to make sure the motor will be safe in most cases.

[Croustibat]

Basically, an ECU does not know what base timing it is set to; so it assumes it is at a given value. The OEM is 15. If you set it on 20, every time the ECU commands a spark, it will arrive 5° sooner.

If enthalpy ECU is programmed to get a 20° base timing, then set it to 20. If you set it to 5, it will have timing retarded 5° all the time.

The main reason for that is usually a less powerful ECU that needs more time to process things (powerful in terms of operations per secons, not in terms of functionnality)

Did you order an ECU or just a chip ? I would be quite surprised if that is just a chip ... why would not they just pull 5° on the whole ignition map to begin with ?

Changing the CAS setting also means fuelling will start sooner/later too ...

[jacobzking]

I ordered the whole ECU but it's just an OEM ECU with a daughter board and some ROMS. so if I leave my timing set to 15, and his ECU is set for 20 I'm running 5 degrees retarded? What is the basic effect of running advanced or retarded?

[fliprayzin240sx]

I ordered the whole ECU but it's just an OEM ECU with a daughter board and some ROMS. so if I leave my timing set to 15, and his ECU is set for 20 I'm running 5 degrees retarded? What is the basic effect of running advanced or retarded?

Timing is how you make power. You want to push the timing as high as possible, without getting detonation. But thats the first time I've heard of any rom tuner telling people to set their base timing to 20 vs 15*.

[turbociv910]

The main reason for that is usually a less powerful ECU that needs more time to process things (powerful in terms of operations per secons, not in terms of functionnality)


:eek2: I cant believe i just read that.
you do realise some of those cas sensors have 360 tiny slots in them and is counted each time it passed by? 360 triggers per revolution.. thats pretty fast to keep up with.

but..
The base timing number is permanently set in the ecu(stock tune). You set timing to that spec(in this case 15) so the engine is running at what it was programmed to run at difference engine loads. If you add a BASE timing of 20*( in a rom tune), your timing map does not increase 5*, only the sync position(cam and crank sensor) is now 5* higher.. If you were to turn the cas to gain 5*, then you would be adding 5* to the whole map.

[Pinggg]

My Enthalpy tune runs 18* timing because E85/higher compression pistons/boost.
Just contact Martin and he will explain to you. No need for a thread.

[!Zar!]

I don't recall being told to change my timing. So I'm just rocking 15*

[cotbu]

No good tuner will ever change the base timing with out telling you, or without you requesting it. And you should support the tuner, even if you buy the tune second hand.