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During break in of new motor (396 SB) we fouled the plugs due to overly rich tune since it was using much higher map values than prior motor/tune. I believe it was caused by my VAFPR not seeing lower values due to MAP at 50 to 80 It was set to 43 lbs fp with no vac line attached.. cam is 236/242 @ .05 on a 112 LSA. I mistakenly thought it happened again after three consecutive cranking starts in my driveway after break in
I took out cranking fuel and leaned out choke values. Now the car will not fire up immediately as it did before . IAC is at 10 steps for idle. I now recognize that I need to add back in for choke values and crank fuel.
Please explain the 3006 port fuel bin RBob provided as far as values for crank. choke is OK per WB.
crank afr shows neg 4.5 at high coolant temps and scaled down to neg .4 at cooler temps. Is the neg adding crank fuel ? I changed that to positive values. Is that my mistake?
crank prime is zeroed out. I left that as is.
crank pulse width multiplier is RPM referenced and is neg 3.9 at 100 rpm and scaled to zero at 0 RPM. I changed that to all zero.
my error. What I stated was from a bin I made march 2019. The 3006 has crank afr at 8.0 scaling down to .8. I went back to stock values of 2006. I will reflash tomorrow morning.
For what it is worth here are my only changes to crank fueling. Not knowing your setup I am unsure if it is any use to you.
I raised my Crank - Prime PW values a decent amount. Seems to start just fine and never needs pedal touched or excessive cranking. Could probably be revisited to get even better start up times but its a nonissue at this stage.
Another thing to look at is your VE tables. Specifically around the low RPM high MAP area. It is used for cranking and needs to be adjusted accordingly.
You probably already knew, so don't take this as insult to your knowledge. More so responding for others reading this through search....
Last edited by dabomb6608; 06-11-2019 at 01:57 PM.
Thank you for your input. I think I may have discovered my error. I think the 3006 .bin is OK with stock values. As I stated the Aero VAFPR may have caused the enrichment issue during break in. Since then I have run maybe 8 data logs and VE Learn. It takes 1-5% of fuel out of low rpm VE tables each time. So I have a leaner table across the board on that. That would address the cranking cells as well. I also smooth the values. I believe that is the 100 MAP cells a 10-100 rpms. Yesterday I had a hard time restarting at warmed coolant temps. Another screw up by me was I neglected to use # lock on lap top so neg values were changed to zero. I thought just changing the BPC to reflect the CID change would take care of tune. It did not. I will change the Crank-Prime (only) incrementally if need be. At idle the IAC shows 10 at 800 rpms. So the throttle blades are open.
06-11-2019, 08:21 AM
