Advanced Timing, Car Feels Slower?

[blk94r33]

Hi all

Recently completed my DE+T, as a result, set the timing to ~12 degrees BTDC from ~15 BTDC for a run-in period (using a Snap-On timing light, on the wire loop near the ignitor, with the TPS disconnected, coolant temp at 83 degrees).

Car is running about 5psi, straight off the actuator, plumbed into the turbo outlet.

Has now been running smooth for a week, so decided to try advancing the timing to get better fuel economy and power.

Tonight, advanced it back to ~15 BTDC (as above) and the car feels like the timing is way out, gets onto boost but just doesn't "move" and is generally sluggish. Switched it off for a few minutes, re-started, same thing. Back to my work. re-set it to ~13 BTDC and took it for another spin, much much better and more responsive.

Everything I've read both on here and the engine manual says that to advance the timing, rotate the CAS ANTI-CLOCKWISE when looking at the front of the car. This corresponds to the timing moving on the balancer. Have gone from just "right" of the 2nd mark from the TDC orange mark (~12), up to the third mark where the car felt slow (~15), now back to roughly the middle of the 2nd and 3rd marks. (~13).

Have I simply found the mark of "peak torque" at the current setting with nothing to gain with more advance?

Any advice? Other than but a GTST?

Mods:

-Stock GTS RB25de

-Platinum plugs, yellowjackets, walbro fuel pump, BP Ultimate

-Stock R34 turbo, stock R33 GTST exhaust, ECU, injectors, SMIC

Edited May 18, 2011 by blk94r33

[zebra]

ECU is probably going going into the knock map at 15deg advance

[blk94r33]

ECU is probably going going into the knock map at 15deg advance

My thoughts also, I read somewhere that the ECU uses the knock sensors to switch between high and low ignition maps, rather than actively change the timing?

Thus the reason I stopped and restarted the car, yet it still felt crap?

I'm looking to get the timing set properly, checked for knock, A/F checked and a power run within a week, just thought it was a bit strange?

[blk94r33]

Anyone else?

[Rolls]

almost certainly going into the low octane knock map, the ecu just saved you possible holes in your pistons!

if you want to advance the timing get someone to tune it properly, it'll last forever and get better results.

Edited May 20, 2011 by Rolls

[paulr33]

buy a GTST or get a real stand alone ECU

you needs lots of control and extra precision given its N/A with a turbo on top

you have to juggle the compression and extra intake temp

recommend powerfc

[blk94r33]

buy a GTST or get a real stand alone ECU

you needs lots of control and extra precision given its N/A with a turbo on top

you have to juggle the compression and extra intake temp

recommend powerfc

That's the long term plan. At the moment with the timing set to ~12-13, i'm getting consistent 11L/100km on around town tanks! Which is probably a 1-2 L/100km gain over N/A minus the horrible 3500ish rpm rattle.

Until I can get the car on a dyno and checked for knock properly, or decent engine management and proper tune, i'll just leave the timing where it is...