730ECM spark question
#1
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Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
730ECM spark question
Hi...
Did my 730 ECM swap today. Started it up and scanned the car.....
Ign. was jumping between 15-24 at idle, If I look at the main spark table it should be minimum 20 deg. Where does it get 15 deg from?
Closed loop, 180 deg F, idle 700-750 RPM, MAP 0,47-0,50 kPa.
/thanks.
/N.
Did my 730 ECM swap today. Started it up and scanned the car.....
Ign. was jumping between 15-24 at idle, If I look at the main spark table it should be minimum 20 deg. Where does it get 15 deg from?
Closed loop, 180 deg F, idle 700-750 RPM, MAP 0,47-0,50 kPa.
/thanks.
/N.
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Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
Its in the code for the ecm :-( Its there basically to maintain an even idle as posible under most circumstances. So u will see the timing vary at idle as the ecm deems necessary to keep the desired idle speed.
I dont know of anyways to disable it. Others here who know more will most likely chime in there 2 cents as well
Later
Jeremy
I dont know of anyways to disable it. Others here who know more will most likely chime in there 2 cents as well
Later
Jeremy
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Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
On my 165ECM I changed in the main spark table to 22 deg. at idle and it would never go under that at idle................
Does the 730 has more than one spark table for idle?
/N.
Does the 730 has more than one spark table for idle?
/N.
#4
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Car: check
Engine: check
Transmission: check
Originally posted by gta324
Does the 730 has more than one spark table for idle?
/N.
Does the 730 has more than one spark table for idle?
/N.
RBob.
#5
Originally posted by gta324
On my 165ECM I changed in the main spark table to 22 deg. at idle and it would never go under that at idle................
Does the 730 has more than one spark table for idle?
On my 165ECM I changed in the main spark table to 22 deg. at idle and it would never go under that at idle................
Does the 730 has more than one spark table for idle?
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Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
very interesting :-)
So if i zero out the SA vs. rpm(ill go check'em out on TC) i can actually stabilize my idle further?(least keep the timing at a constant degree) hmmmmmmmmmmmm
sound slike something i will be playing wiht shortly
thanks rbob
later
Jeremy
So if i zero out the SA vs. rpm(ill go check'em out on TC) i can actually stabilize my idle further?(least keep the timing at a constant degree) hmmmmmmmmmmmm
sound slike something i will be playing wiht shortly
thanks rbob
later
Jeremy
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Car: check
Engine: check
Transmission: check
Originally posted by 3.8TransAM
very interesting :-)
So if i zero out the SA vs. rpm(ill go check'em out on TC) i can actually stabilize my idle further?(least keep the timing at a constant degree) hmmmmmmmmmmmm
sound slike something i will be playing wiht shortly
thanks rbob
later
Jeremy
very interesting :-)
So if i zero out the SA vs. rpm(ill go check'em out on TC) i can actually stabilize my idle further?(least keep the timing at a constant degree) hmmmmmmmmmmmm
sound slike something i will be playing wiht shortly
thanks rbob
later
Jeremy
RBob.
#9
I was under the impression that the idle timing change table also insured frequent O2 sensor transitions, for the idle AFR set point. Isn't that where the "slow O2 transitions" table is used? I need to go look at the hack again - can't remember which was which AFR calc...
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