Stock Spark table q's
#1
Stock Spark table q's
Ok, from what I gather from reading (I may be way off) When you nail the throttle to the floor, your timing should advance.. I was looking at my stock spark table. I noticed the higher the MAP value (more throttle?) at low RPMS, the less timing the table allows.
for example at 100 kpa, and 400 rpm. its actualy taking out .7 degrees of timing.. why is this? Im feeling kind uneducated here., i had assumed when you put the pedal to the floor, the timing would advance to allow for more power on accel...maybe its for fuel economy and longevity of the motor?
I know im probably asking for along complicated answer.. but if your willing to type it up, I am willing to read..if you have anything to add to help my understanding of map vs timing I would sure appreciate it.
Just for giggles here's my table (bone stock 350 with tbi mods)
for example at 100 kpa, and 400 rpm. its actualy taking out .7 degrees of timing.. why is this? Im feeling kind uneducated here., i had assumed when you put the pedal to the floor, the timing would advance to allow for more power on accel...maybe its for fuel economy and longevity of the motor?
I know im probably asking for along complicated answer.. but if your willing to type it up, I am willing to read..if you have anything to add to help my understanding of map vs timing I would sure appreciate it.
Just for giggles here's my table (bone stock 350 with tbi mods)
Code:
RPM MAP (Kpa) 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 400 20.0 20.0 20.0 20.0 20.0 18.3 17.2 12.3 11.3 9.1 6.3 4.2 3.2 2.1 1.1 0.0 -0.7 600 20.0 20.0 20.0 20.0 20.0 18.3 17.2 12.3 11.3 9.1 6.3 4.2 3.2 2.1 1.1 0.0 0.0 800 20.0 20.0 20.0 20.0 20.0 20.0 20.0 16.2 14.1 10.2 9.1 5.3 4.2 2.1 1.1 0.0 0.0 1000 20.0 20.0 20.0 20.0 20.0 20.0 20.0 18.3 15.1 13.0 10.2 7.0 5.3 3.2 1.1 0.0 0.0 1200 20.0 20.0 20.0 20.0 20.0 20.0 20.0 18.3 16.2 14.1 11.3 9.1 7.0 5.3 3.2 2.1 1.1 1600 21.1 21.1 21.1 21.1 21.1 21.1 21.1 19.0 18.3 15.1 13.0 11.3 9.1 7.0 5.3 4.2 4.2 2000 22.1 22.1 22.1 22.1 22.1 22.1 22.1 20.0 19.0 16.2 14.1 12.3 10.2 9.1 7.0 6.3 6.3 2400 23.2 23.2 23.2 23.2 23.2 23.2 23.2 22.1 21.1 18.3 16.2 14.1 12.3 11.3 9.1 9.1 8.1 2800 25.3 25.3 25.3 25.3 25.3 25.3 25.3 23.2 22.1 19.0 17.2 15.1 13.0 12.3 11.3 10.2 9.1 3200 26.0 26.0 26.0 26.0 26.0 26.0 26.0 24.3 23.2 22.1 18.3 17.2 16.2 14.1 13.0 12.3 11.3 3600 27.1 27.1 27.1 27.1 27.1 27.1 27.1 26.0 24.3 22.1 20.0 18.3 17.2 15.1 14.1 13.0 12.3 4000 30.2 30.2 30.2 30.2 30.2 30.2 30.2 30.2 25.3 23.2 21.1 20.0 19.0 17.2 17.2 16.2 15.1 4400 30.2 30.2 30.2 30.2 30.2 30.2 30.2 30.2 26.0 24.3 22.1 21.1 20.0 18.3 18.3 18.3 17.2 4800 30.2 30.2 30.2 30.2 30.2 30.2 30.2 30.2 26.0 24.3 22.1 21.1 20.0 18.3 17.2 16.2 15.1 5200 30.2 30.2 30.2 30.2 30.2 30.2 30.2 30.2 26.0 24.3 23.2 22.1 21.1 19.0 18.3 17.2 16.2 5600 30.2 30.2 30.2 30.2 30.2 30.2 30.2 30.2 26.0 24.3 23.2 22.1 21.1 19.0 18.3 17.2 16.2 6000 30.2 30.2 30.2 30.2 30.2 30.2 30.2 30.2 26.0 24.3 23.2 22.1 21.1 19.0 18.3 17.2 16.2
#2
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Re: Stock Spark table q's
Originally posted by lykan
Ok, from what I gather from reading (I may be way off) When you nail the throttle to the floor, your timing should advance.. I was looking at my stock spark table. I noticed the higher the MAP value (more throttle?) at low RPMS, the less timing the table allows.
for example at 100 kpa, and 400 rpm. its actualy taking out .7 degrees of timing.. why is this? Im feeling kind uneducated here., i had assumed when you put the pedal to the floor, the timing would advance to allow for more power on accel...maybe its for fuel economy and longevity of the motor?
I know im probably asking for along complicated answer.. but if your willing to type it up, I am willing to read..if you have anything to add to help my understanding of map vs timing I would sure appreciate it.
Just for giggles here's my table (bone stock 350 with tbi mods)
[/code]
Ok, from what I gather from reading (I may be way off) When you nail the throttle to the floor, your timing should advance.. I was looking at my stock spark table. I noticed the higher the MAP value (more throttle?) at low RPMS, the less timing the table allows.
for example at 100 kpa, and 400 rpm. its actualy taking out .7 degrees of timing.. why is this? Im feeling kind uneducated here., i had assumed when you put the pedal to the floor, the timing would advance to allow for more power on accel...maybe its for fuel economy and longevity of the motor?
I know im probably asking for along complicated answer.. but if your willing to type it up, I am willing to read..if you have anything to add to help my understanding of map vs timing I would sure appreciate it.
Just for giggles here's my table (bone stock 350 with tbi mods)
[/code]
Lean mixtures are slow to burn so you need more time, ie advance for them to burn so in cruise mode when the engine is running lean you need alot of advance.
WOT developes alot of heat, and the mixture lights easy, so not as much timing is needed.
The only time the engine sees the 100 K/Pa 400 entre is went the engine first starts as is gaining speed from the starter spinning the engine to actual idle RPM
Long explainations made short.
HTH
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WOW
I've been flogging cars for along time now and I have never understood timing as well as I do now.
Thanks Grumpy, very well explained
ED
I've been flogging cars for along time now and I have never understood timing as well as I do now.
Thanks Grumpy, very well explained
ED
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