Help please - getting started on SD, new LS2 402
2002 SS with a new 402 LS2
11.5:1 compression ratio
244/250...114 LSA cam
AFR 225 62cc heads
Kook's headers
FAST 90/90 Intake/TB
SLP 85mm MAF
42lb Racetronix injectors (48.83lb/hr @ 58psi)
255lph fuel pump
Manual transmission
What I've done to the tune:
1 - Adjusted for cylinder size
2 - AIR delete
3 - Rear O2 delete
4 - CAGS delete
5 - adjusted fans for 160 degree thermostat
6 - adjusted rev limiters (7200 rpm)
7 - adjusted for fuel injectors (Flow Rate vs KPS information taken from the spreadsheet floating around, and Offset vs Volts vs VAC decreased across the board 12%)
8 - Set up for SD (turned off MAF, adjusted error codes, etc.)
9 - Adjusted idle tables and mapped the main spark advance tables for a smooth transition
10 - Adjusted VE table to a semi-known rich table (advised on HPT forum)
11 - Added 2g/sec fuel the base running airflow table
At this point, this is what I know:
- I have adjusted the timing around idle conditions to get it started and what seemed to be running smoothly (would hold idle, would come back when I revved it a bit in neutral). Commanding the idle through the VCM controls seemed to provide the lowest MAP and the "best sound" at a little over 30 degrees, so I set the tables to be around 28 in order to let the PCM have a little control...
- the VE table is rich and needs to be brought in line via driving around and logging
- it will not hold an idle once I start moving (I have keep giving the car gas whenever I go back into neutral or it will die)
- it bucks like crazy under low load conditions
- won't start or run at all now (unless I hold down the gas)
My assumptions are:
- the spark tables are not anywhere close to where they need to be. I'm not sure how I should be adjusting them from the stock tables to get me driving confidently though.
- there is something else going on when I let off the gas that is killing the car - DFCO is off, MAP/Advance/AFR all seem to stay constant but the rpms just drop until it dies unless I give it gas
Any advice? I'm at the point that
describes me... Maybe I'm just overloading myself with data and I just need a break.Current tune and 2 logs are attached below. The "VE 3" log is driving home from the gas station - you can see the surging at around 1:20. The "Won't Start 2" log is precisely that, 10 minutes after I got home and went back out it wouldn't start and idle at all.
Thanks for any advice.
long winded, I have had a few this evening.
Also check your base idle timing. You want it at a midpoint between MBT and slow down retarded so that the ECM and vary eitherway to either speed up or slow down idle to manage things.

I will try opening the blade a tad more and see if I can pull the IAC counts down. I put it between 1-2% yesterday and reset the sensor, and didn't even think about doing more last night. What is the max that one would really want to go before deciding to drill?
ringram - I'm not sure what you imply by "running airflow action number 11." Would you mind expanding on that thought?
I appreciate the help - just need the neighbors to wake up so I can start trying things out again.
At what I believe is the max I can give it - I am still getting IAC in the 180-210 range. It is this high regardless of where the set screw is. What am I missing that effects this? Should I be making adjustments to the IAC Steps vs Effective Area? The Desired IAC Area Max?
I don't mind drilling a hole if that is what is required, but I also don't want to jump the gun here. I would think that something else needs to be adjusted since I am not making any improvements with the set screw whatsoever...



