gear_grinder

iTrader: (4)

hi

i was recently reading a magazine that featured rotary engines and a suggestion was not to run split timing, but gave no explanation of what split timing is. i'm guessing its the time delay between the leading and trailing spark plug ignition. why should i not have split timing (guessing has to be detonation or something destructive), and if it is bad how can i change the ignition setup to not run split timing.

Thanks!

Derekcat

iTrader: (8)

I believe it runs split timing from the factory..

Perhaps they believe that it shouldn't be adjusted?

Jimmy2222

iTrader: (3)

Split timing is the split between spark in your lead/trail sparks (I believe). don't wanna touch the recommendation, as it can also be a bad idea if you can't tune very well.

arghx

iTrader: (3)

Reducing split usually means advancing the trailing timing relative to the leading. Advancing timing can pick up some power but can also lead to knock. No split engines tend to be naturally aspirated race motors.

Black Knight RX7 FC3S

iTrader: (7)

with no split timing, you have that chance that trailing will fire first then the leading. WHich would lead to detonation/knocking, harmful to the engine especially on a turbo engine.

gear_grinder

iTrader: (4)

so would you actualy want to move the leading to the trailing timing and get rid of the split timing that way and also retard the ignition timing @ the same time?

RotaryRocket88

iTrader: (7)

0 split would mean the leading and trailing timing values would be the same. Take a look at the timing maps in this thread, and you'll see a bunch of low-load cells that have 0 split on an N332 ECU: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/stock-s4-turbo-timing-maps-warning-those-stock-ecu-943159/.

Pele

iTrader: (28)

Basically, it's only adjustable if you have a modified/aftermarket ECU that you can tune or have a distributor (1st gen) that has been disassembled and locked...

Since locked no-split timing requires special equipment, if you have the ability to lock your split to 0 then you probably already know the implications of setting it and should know what you're doing with it.

MadScience_7

There was a thread in one of the performance sections that had a lot of info on no-split and even negative-split timings.

[canIfindit?]
[indeed]

https://www.rx7club.com/rotary-car-performance-77/negative-split-443709/