Twin plug timing
 

Looking for some a suggested timing curve for a 2.4 twin plug motor recently completed. Timing is via Haltech engine management and although the motor is currently running I would appreciate suggestions as to what the optimum timing curve should look like.

Regards
Chris

You can start with 10 Deg initial advance (for starting), then 5 deg at idle, then ramp the timing linearly to 26 deg at 3000rpm, then hold at 26 from 3000-6000. This should get you started , and is a base for the fine tuning of advance.

First get safe fuel mixture at all rpm ranges.

To get the timing curve idealised, you need to get the car on a dyno that can load the vehicle. Work through every rpm range and fine tune the timing. Watching the torque of the engine profduces as you adjust the timing, you will hit peak power at a given rpm, then the power will fall off. The timing setting when you are at peak power is optimum, but doesnt allow any room for preignition, so back the timing away a bit ( you will give up some power though)

Haltech software is really easy to work with, The screens for the igniton maps show exactly which cell the engineis operating in and allows on the fly adjustment.

I generally started with 6 degrees retarded from the stock curve when twin plugging. However what Tim sez about the dyno is important. Generally when you've twin plugged a motor you have done other things as well (cams, etc..) so the stock curve is only approximate...

Tim & Chris

Thanks for the info, actually the initial settings suggested by Tim are exactly where I am now. Fuel maps are all good (and safe verified with Wide Band O2) with the dyno being the next step. Tim I must agree the Haltech is a nice system offering everything I want and more.

Chris