I finnished my fuel curve and am ready to play with timing. I have been searching for some general principles to use when adjusting timing but have found nothing cooncrete. Do I just start adding small increments over the entire rpm range until I see knock or loss of power? Are there certain rpm ranges that need more timing than others? Any tips would be great. Thanks

 

Anyone?

 

Please.

 

Um, you only allowed sixteen minutes for a reply before asking again. Give people a little bit of time.

Look to your stock timing curve to get an idea of what you want to do. The engine can handle more timing the farther away it is from its VE peak. At around 3500 rpm, you'll want minimum timing advance, but you can tolerate more as you go away from that point. At redline there's already lots of timing, but because of the multiplication factor of the high rpm, any small increase in timing can get you lots of power (assuming you have no detonation problems). But keep in mind that a detonation event at high boost and high rpms can be very damaging to the motor. Use the knock sensor features of the ECU+, and/or additional diagnostics to make sure you're not hurting anything. And always run as much octane as you can.

--Dan
Mach V
MachEVO.com

 

So. Dan. Basically you want to NOT advance much before maxium TQ? and I understand the advance in upper RPM. Does the ramp up (of timing curve) proportional to the RPM raise?
And right now I have my knock limit at 2.4V to pull 5deg. Is it too high? I mean, I have never seen the Knock voltage(on my car anyways) goes higher than 1.6V.
Thanks for your input

 

Sorry, I'm impacient. Thanks for the info though Dan, it helps. By the way, I was really impressed with my ECU+ purchase from Mach V. I'm sure this is a stupid question but I'm bad with abreviations, what is the ve peak?

 

this is good advice.....and remember the change of octane also means a change in timing...

 

Maximum Volumetric Efficiency.

--Dan
Mach V

 

You can run more timing the farther you are from maximum volumetric efficiency, which is about where your peak torque is. (Farther in either direction. You can run more timing at low rpm, too.) But keep in mind that the factory ECU does a pretty good job of doing that already, so be cautious in trying to add timing. Detonation at high rpm & high boost can be fatal to your engine. Look at the factory's timing and learn from that.

--Dan
Mach V
MachEVO.com

 

Thanks Dan. I appreciate your responses.

 

Pretty much MBTT

 

I may be the only one, but I don't know what that means.

--Dan
Mach V
MachEVO.com

 

maximum breaking torque timing or some may say mbt

 

I had to set about -4 timing from 5500 to redline on 91 octane, 1.5bar peak, about 1.3bar at redline, for there to be no power-robbing knock. I actually gained power doing this, and of course safety.

Be sure to keep an eye on your knock volts when messing with timing. You can knock enough to blow your motor even at 10.8 AFR if you tried hard enough.

 

^Thanks a lot. I'll try this. I still haven't played with timing because I've been really busy. Thanks again.