egr spark retard

[fuelbreak]

i'm adjusting my spark tables and have a couple of questions that i haven't found the answers too. First can i turn off my egr spark retard. i'm not using the egr or at least my datalog has no egr. second i'm adjusting my spark tables and can't seem to add spark at high map without getting alot of knock counts. should i advance it more to get through this or is the high map mid rpms(2200-3400) that sensitive? i only added a couple of degrees advance and was getting 1700 knock count. also the open and closed spark tables should they be the same? Or when does the open spark table apply? still tuning and retuning just hoping for a little clarity. i'm on the 7427 ecm OD mask and bjym bin. 95 gmc ext. cab, 5.7 4l60e tranny, ultimate tbi, tbi spacer, pod spacer, k&n filter, dryer vent intake, 3"cat back exhaust. Thanks for any input/ help

[jim_in_dorris]

If you remove the timing do the knock counts go back down, what grade gas are you running, what do the BLM's and INT's say at the time you see all the knock counts?

[fuelbreak]

i'm running 87 oct gas. My BLM and INT are at 28 because i'm in wot. O2 sensor says rich my pulse width is 7.4 in the 2600 to 3000 range then drops down to 7.2 up to 3400 then below 7. could they be lean knocks? i'm using stock injectors at 12psi. i adjusted the open throttle spark table and will make a run today.

[jim_in_dorris]

It's possible you are going lean, you may need to add some pump shot to that, you aren't going static, so you can still add fuel. Did changing the spark table help any? also you could try running premium and see if that helps

[xch3no2]

Max out the "minimum CTS to allow EGR" and no EGR retard will occur. There are also other ways to dismiss the EGR (TPS & MAP functions, zero the commanded EGR duty cycle table ect). Sounds like you got a little SA work to do, don't forget to use the knock-spark retard tools. Have fun!

[fuelbreak]

ok 4 runs later i've added PE its' now calling for AFR of 12 at WOT and taken away SA @95kpa from 2000 to 3600 2 to 4 degrees below stock now and will make a run tomorrow and see. i've also been adding spark in the middle rpm map areas and have my blm's saying i'm lean now. is that normal? my graph seem to be smoothing out on the ve, but i seem to be developing a hump in my sa table as i go up through the rpm band that is on the back of the curve that i am getting as my map increases. thanks for the help you've given so far hoping for just a little more.

[fuelbreak]

still getting knocks, about 700 in a 40 sec wot run, adding fuel and taking away spark

[xch3no2]

Your EGR delete will require a reduction in spark lead (I would expect 5-7*) and increase fuel requirement. Yes advancing the timing can show leaner up to a point (hotter combustion/exhaust). Other than using Knock Retard look at your PE/SA (in constants) and max retard in PE (tables) (IDK what factors are involved w/PE/SA Correction, temp & pressure I suspect) to see what you can do. Maybe pull out some lead there. Some guys disable PE to work with their VE tables for a more accurate baseline and minimizing use of PE, I have yet to try it that way, sometime soon seems likely.

[fuelbreak]

Thanks xch for the info. I've taken out all of my PE SA and i've left my PE alone except for richening it for suspected lean wot conditions. Put in my new fuel regulator and saw the pressure gauge was broke so getting a new one expressed out. adjusted the regulator until datalogs were only showing slightly lean on tune from before installing regulator. Leaving it there until get gauge and can see what is going on.