igniton timing
 

Ok on some ignition maps on the top right thy go into negative values this confuses me.

I have read you first worm up the engine. Set the entire ignition map to what ever your base timing is so lets say you set it all to 13 btdc then you go out and set your base timing to 13 btdc rev it up a little it should always be at 13 btdc now your map and base timing are in line. But I have read you can only go as low as you base timing. The book I was reading was a bit old. And seemed to only apply to system using a signal crank sensor input.

With honda's tdc,cyp and ckp sensors will the negative value actually be true?

Re: igniton timing
 

Okay, i think i know what you are saying. If you look at a ignition map in boost, where the negative values are, do you think you will ever have that??? My negative values show up at like 9psi at 1000 rpms, if you can get 9psi at 1000 rpms you are one cool dude. Im not even sure if the engine would run, it looks like it could on paper but for real i don't know. But yes you can spark closer to top dead center then 13btdc or simply retarding timing. If you couldn't then you might get det under a load like say 9psi at around 5000 rpms. It depends on the efficiency of your turbo setup. I think i am making sense here? Anyone..... :S

Re: igniton timing
 

Some of the s manager ---- negatives show up in the n/a section 1000rpm wot. I not using hondata but I was using the ignition maps for a reference on a b20.
Ya I would never think you would hit that much psi that low.

The book I was reading seemed to only apply to signal input ignition systems like on a old 350 with a pick up on the crank and a lot of the msd system. Not really sure why I even read it, but hay whatever.

The other thing I was thinking about is antilag retards the timing a ---- load to spool up. Plus I thing knock capable systems retard your timing lower then what you set your base timing at some times. So negative values must work just confuses me.

Re: igniton timing
 

Yeah you got me thinking, so a negative value would mean that the spark occurrs when the piston starts going down on the power stroke right?? Wow, i have never even thought about this. Mine in N/A would be 750 rpms at wide open throttle, you could probably advance timing alittle which is -2.75. <-- i don't think that would ever get there either on my car or it might just kill the engine lilke if i dumped the clutch in 3rd gear. Is this a base map someone made for starting safe?? I don't think you have much to worry about, your timing just sounds more retarded then factory specs. DO you have what honda wants. My N/A side is very close to factory specs maybe just a little retarded from specs.

Re: igniton timing
 

Ya its just a base map from hondata s300 for a b20 I was just using it for a reference. Like you say the motor probably never operates in the section. Ya It just confused me I would be like the pressure build is chasing the piston down the hole. I can see it on a turbo set up but no a n/a motor.