Adjusting ignition timing

[pmurr181]

Hey guys,

So I have a r32 gts-4 running full 3 inch exhaust no cat, with intake and synapse BOV, boost controller set at steady 12. Replaced all the plugs, sensors, fuel filter, cleaned maf, and tps, AAC, and timming adjusted.

I was wondering if it's bad to have the ignition timing set at 20degress vs 15 with these mods. My car seems to run much better at this ignition timing. However, regardless of what ignition timing I run I back fire soo loud and if I boost and then let off it pops out a little back fire.

Any suggestions

[R33rr]

check you spark plug gap and coils

[DreadedFist]

Mine did that too when I had 1.1mm plug gap and similar mods. Down to 0.8mm gap fixed it. No more burbling when decelerating and no more fireballs. Is it tuned for the externally venting blow off valve? Dumping metered air causes temp rich condition that'll shoot fire.

[pmurr181]

Hey i have a synapse synchronic BOV recirculating and i think i am going to chane my plugs and put the timing back to 15.

[Skym]

Manual is 15 degrees BTDC and auto is 20 degrees BTDC at 650rpm for CAS on RB20DET. Also have to note that idle stabilisation tables adjust ignition timing + or - 5 degrees or so which makes it hard to set correctly.

Some say the method shown in this manual below on page 10 is the accurate way to set CAS, as avoids using the black wire on back of engine (coilpack loom?, for cylinder 1) that sends the + and - 5 degrees ignition timing signal -

http://www.linkecu.com/support/documentation/g1-engine-management-documentation/gtslinkinstructionmanual

I think they used a cable off a distributor type engine for between coilpack, sparkplug.

There is a way to force stock ECU into not using idle stabilisation tables. I think by unplugging TPS (idle contact inside TPS makes stock ECU switch to idle stabilisation tables) is one way. Also make sure there's no intake airleaks. Or unplug o2 sensor, which stock ECU is adjusting ignition timing for (lean, rich) due to intake airleaks or other (too thick oil, etc).

If using auto ECU in manual conversion it might run better at 20 degrees BTDC, as ECU ignition map is tuned to suit. But I haven't seen any difference between the ignition maps on manual and auto stock ECU's when comparing them, but some tuners say there is a difference.

When mine popped flames from exhaust, it was due to faulty / slow to react o2 sensor making engine stay rich for longer. Unplugged it and checked that engine wasn't running too lean via wideband and engine ran better / smoother. Also adjusted TPS, as was slightly out (not touching idle contact).

Sparkplug wise, stock is NGK PFR5A-11. You'll need one heat range colder due to higher cylinder temps, NGK PFR6A-11 regapped to 0.8mm.