There is an option in the main setup page to use Advance Map 2 for Twin spark offset - ie trailing degrees.
And no, I wouldn't expect any gain except maybe at light loads/idle. Even rotaries make good power at zero trailing split.
Twin Spark Offset ?
- ignitionautosport
- Posts: 577
- Joined: Wed Jul 27, 2011 5:30 am
- ECU Model: S80 Pro
- Location: New Zealand
- Contact:
Re: Twin Spark Offset ?
| '94 GSR Lancer | '96 Toyota Carib 20V | '83 Toyota Starlet | www.ignitionautosport.co.nz |
Re: Twin Spark Offset ?
DTA's definition of "twin spark" may mean something else but the manual does state it can run 2 plugs per cylinder
DTA Manual wrote:
TWIN SPARK?
S60PRO and above. Only use this when the engine has 2 spark plugs per cylinder. First spark plug coil outputs coil 1 to coil (number of cylinders), second plug outputs are coil (number of cylinders) to coil (number of cylinders x 2), that is cylinder 1 first plug is on coil output 1, second spark plug on cylinder 1 is coil output (number of cylinders + 1).
This is how I run my COPs. I didn't want the added complication of COP firing angles, just straight forward wasted sparkDTA Manual wrote: This ability to run twin spark mode can be very useful for an engine which has individual coils but no cam sensor. Wire the coils as you would for running them with a cam sensor fitted and select twin spark on.
DTA Manual wrote: TWIN SPARK OFFSET
S60PRO and above. Allows small delay (in degrees) between 2 sparks on the same cylinder. If 0 then both sparks are at the same time. If 10 then the second spark occurs ten degrees later. Note that all advance figures relate to the first spark.
-
- Posts: 8
- Joined: Mon Aug 22, 2011 8:20 pm
- ECU Model: S60 Pro
- Firmware Version: 61
- Location: Toronto Canada
Re: Twin Spark Offset ?
Next question , why do rotary engines use twin spark ?
Re: Twin Spark Offset ?
Good question!
Looking at this diagram, I'd say it's either to help push the rotor round (staggered firing) or just to give a bigger burn area?
Looking at this diagram, I'd say it's either to help push the rotor round (staggered firing) or just to give a bigger burn area?
-
- Posts: 96
- Joined: Sat Nov 12, 2011 6:24 pm
- ECU Model: S100 Pro
- Firmware Version: 61
- Location: Montreal, Canada
Re: Twin Spark Offset ?
Twin spark is simply because the combustion chamber is very long. Using 2 spark plugs solves bad flame front propagation speed issues. Rotaries run pig rich to start with which is hard to ignite at low RPM/load and this helps.
As stated above, they run split from the fatory to help with emmisions and low load conditions but many tuners running stanalones will run them sync'd to simplify things.
There are actually some race engines (Mazda 787B Lemans car) running a third plug right in between the 2 seen in the diagram above. No idea about the timing split on those...
Cheers!
As stated above, they run split from the fatory to help with emmisions and low load conditions but many tuners running stanalones will run them sync'd to simplify things.
There are actually some race engines (Mazda 787B Lemans car) running a third plug right in between the 2 seen in the diagram above. No idea about the timing split on those...
Cheers!