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240sxpooter
April 6th, 2015, 01:30 AM
Hello,
I am new to EFIlive (used to be a HP tuners guy) and I am having a issue on a car I'm tuning. I've attached a screen shot, log,dyno chart, and tune.

Basically I am getting a jittery timing curve in my logs and I'm unsure why. The car is getting close to being completed and this is one of the last concerns I have.

TMS 408
Prochaged DSC-1 (making 10-11psi)
E75
127LB injectors
Descaled VE and injectors to fix P1514 <-- Load was going to high

I feel like the logs my be incorrect but I'm not sure. Any help would be much appreciated.



182171821618218
240sxpooter
April 6th, 2015, 01:32 AM
18219

Image of concern
joecar
April 6th, 2015, 03:02 AM
I'm looking at your files...

so you're running MAF-less with LTFT...?

( BTW: your B3647 is incorrect (it still has the B3605 data), when you applied the COS you neglected to edit B3647 )
240sxpooter
April 6th, 2015, 03:15 AM
Currently I have LTFT on. There where many issues getting the car running and the LTFT helped with the fueling issue.
Also I just fixed the B3647 table (explains the super rich OL fueling)
240sxpooter
April 6th, 2015, 06:53 AM
Is it possible that the A0010 map is coming into play 14psi early? Like the Map axis scaling is off +14psi?
joecar
April 7th, 2015, 04:03 AM
A0010 kicks in when operating point leaves B0101 and enters A0009... your A0010 has a smooth line so it is not responsible for the jittery timing.

Look at the pids that have names starting with "EST_" (ending with "_DMA"), log these to see if they will give us a clue.
240sxpooter
April 7th, 2015, 02:47 PM
A0010 kicks in when operating point leaves B0101 and enters A0009... your A0010 has a smooth line so it is not responsible for the jittery timing.

Look at the pids that have names starting with "EST_" (ending with "_DMA"), log these to see if they will give us a clue.

It was a silly oversight. Burst knock retard was all over the place :online2long:

After this timing was spot on and 14* ended up making 790whp and 760wtq.


Thanks for the help.
joecar
April 8th, 2015, 03:08 AM
B6212 only, or B6210 also...?

Good job... post a log of that run if you have it.
240sxpooter
April 8th, 2015, 05:44 AM
B6212 only, or B6210 also...?

Good job... post a log of that run if you have it.

B6212 only- I zero'd it out
18231
240sxpooter
April 8th, 2015, 05:44 AM
18232
Highlander
April 14th, 2015, 04:04 PM
Very well done.
240sxpooter
April 15th, 2015, 12:34 AM
Some notes about tuning on the street.

~After letting the customer drive the car I noticed that the ECU would stay in "closed loop" longer than I would like so I changed the triggers to a lower RPM and TPS as the supercharger would make boost at 30% throttle.
~The AFR stayed about the same as on the dyno so it was fine
~With this engine setup and injectors it did not like idling below 1050rpm. any less and it would get real choppy.