Ping in Vacuum Fix?

I noticed recently that while I'm cruising on the interstate at about 65-70 mph (between 2000-2500 rpms) and get on the throttle just enough to bring it up to about -2 in.Hg to 0 psi, I get a slight ping. If I get on the throttle enough to pass this point and get into boost, it does not ping. This is because I have timing being added in as soon as boost kicks in. This is how my timing map on my URD unit is set up. I think the reason this ping below boost is present is because my high end timing map (>3000 rpms) is very advanced. Above 3000 rpms, the ecu uses the knock sensors to advance the timing as much as possible until it senses knock. Since my URD unit makes me run rich when I get above 3000 rpms, the tendency to knock to reduced greatly. This allows the ecu to run the timing very advanced. The low end timing map is extrapolated from the high end timing map. SO this means my low end timing(<3000 rpms) is more advanced than it would be if the motor was N/A. This causes me to ping in the situation I mentioned earlier. Would it be possible to use my R4 software and add a small amount of timing in the 2000-2500 rpm range BEFORE I get into boost? I am not sure how adding timing in before boost would affect the way the ecu operates. What do you guys think? I think it will work, just want to check. Sorry for the novel! Thanks.

 

Bump. Any suggestions?

 

You need pull timing in that area. The Split Sec piggy can only pull timing anyway not add it. If you are referring to adding to the value (from 3 to 4 or 5) then tha is acctually redarding timing not adding it.

increase the number in only one or two cells areound the area it is pinging at a time so you target the area. Connect your laptop to the piggy back while running the the R4 s/w and see where you hear the ping in relation to where the courser is on the timing map. That is your target.

 

Yea thats what I meant by "add". I was just worried if there was an issue with retarding the timing while not in boost. I went ahead today and retarded it a tiny bit in the area I mentioned. Gonna test it out tomorrow.

 

Cool, report back.

 

Still does it some. Looks like I'll add in some more retard and see how it goes.