Let's see your fully tuned timing maps
Sep 27, 2014, 12:27 AM
#2551
With gasoline and since it has a higher content of energy vs ethanol, many are able to predict where that sweet spot occurs not by measuring pressure but with observing a study idle that can overcome the pumping loses and external loads (electrical & mechanical).
According to wiki Gas is at ~44 Mj/kg and Ethanol is ~ 26.
Maybe some of the guru's can pitch in and explain as well.
Hope this helps!
ps. Under 500 rpm, the ecu is in cranking or start-up mode and I don't think it runs off the spark surface, if you log a start-up, then you will note a max of 5* if I am not mistaken!...someone may confirm?
Nov 27, 2014, 10:04 AM
#2553
I think in the ideal world, you would need to fire at TDC to create the biggest pressure rise to move the piston when the moment on the crank is at its highest; however, this is done with the assumption that at TDC you will burn all the fuel resulting in the highest “push/pressure”….. Unfortunate this is not the case since flame propagation depends on a number of variables, fuel energy content, geometry of the combustion chamber, compression…etc hence why we need to fire pre-TDC inorder to achieve the best trq or results.
With gasoline and since it has a higher content of energy vs ethanol, many are able to predict where that sweet spot occurs not by measuring pressure but with observing a study idle that can overcome the pumping loses and external loads (electrical & mechanical).
According to wiki Gas is at ~44 Mj/kg and Ethanol is ~ 26.
Maybe some of the guru's can pitch in and explain as well.
Hope this helps!
ps. Under 500 rpm, the ecu is in cranking or start-up mode and I don't think it runs off the spark surface, if you log a start-up, then you will note a max of 5* if I am not mistaken!...someone may confirm?
With gasoline and since it has a higher content of energy vs ethanol, many are able to predict where that sweet spot occurs not by measuring pressure but with observing a study idle that can overcome the pumping loses and external loads (electrical & mechanical).
According to wiki Gas is at ~44 Mj/kg and Ethanol is ~ 26.
Maybe some of the guru's can pitch in and explain as well.
Hope this helps!
ps. Under 500 rpm, the ecu is in cranking or start-up mode and I don't think it runs off the spark surface, if you log a start-up, then you will note a max of 5* if I am not mistaken!...someone may confirm?
Nov 27, 2014, 10:06 AM
#2554
Dec 7, 2014, 11:02 PM
#2556
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my tuning laptop got knackered, so don't have access for all my files in it..
but there is no knock at peak torque area and at higher rpms as well
I mainly suffer from spool-up knock, somewhere in 180-300 load area
is spool-up timing high ? afrs in that area are 12.6 tapering to 11.6
but there is no knock at peak torque area and at higher rpms as well
I mainly suffer from spool-up knock, somewhere in 180-300 load area
is spool-up timing high ? afrs in that area are 12.6 tapering to 11.6
Last edited by stunt2; Dec 7, 2014 at 11:06 PM.
Dec 8, 2014, 03:36 PM
#2558
my tuning laptop got knackered, so don't have access for all my files in it..
but there is no knock at peak torque area and at higher rpms as well
I mainly suffer from spool-up knock, somewhere in 180-300 load area
is spool-up timing high ? afrs in that area are 12.6 tapering to 11.6
but there is no knock at peak torque area and at higher rpms as well
I mainly suffer from spool-up knock, somewhere in 180-300 load area
is spool-up timing high ? afrs in that area are 12.6 tapering to 11.6
Dec 16, 2014, 04:57 PM
#2559
well that maybe true however you normally dont want to be on the edge of a motor knocking. You never want to tune a car by upping the timing and then as soon as it knocks lowering it by a degree, you tune for power. If a car makes 455hp at 9 degrees and knocks and then makes 454hp at 8 degrees and doesnt knock but makes 450hp at 7 degrees, you put that car at 7 degrees. This is why if you have access its ALWAYS better to tune on a load based dyno so you can go cell to cell and tune based off power and tq not just when the car stops knocking. Your AFRS are fine for spool up in my opinion. I cant see your timing map right now though.
Well said.
Mar 20, 2015, 11:41 PM
#2560
What do u guys think about mine?
Idle 14.6-15.2 Crusing is the same.
Mods Stock injectors, Kelford 272, Tomei turbo, TBE, 10.5;1 pistons.
It was tuned at 22.5psi and since I have turned down the boost bout little over a full knob.
Im getting it retune in 2-3 weeks.
I'll do some logging tmrw.
Mar 22, 2015, 10:18 AM
#2561
What do u guys think about mine?
Idle 14.6-15.2 Crusing is the same.
Mods Stock injectors, Kelford 272, Tomei turbo, TBE, 10.5;1 pistons.
It was tuned at 22.5psi and since I have turned down the boost bout little over a full knob.
Im getting it retune in 2-3 weeks.
I'll do some logging tmrw.
Mar 22, 2015, 08:23 PM
#2562
Mar 23, 2015, 06:26 AM
#2563
-Too much timing from 100 load through the rest of the load range
-At peak load you should be between 0* and 4* timing and end around 10* to 13* at 7k with your boost level and mods
- Timing should vary from cell to cell no more that 5* with a 20 load difference and 3* on a 10 load difference
Hope this helps you.
Mar 26, 2015, 06:44 AM
#2564
Start looking through this thread for examples. The biggest things that are issues with your map are:
-Too much timing from 100 load through the rest of the load range
-At peak load you should be between 0* and 4* timing and end around 10* to 13* at 7k with your boost level and mods
- Timing should vary from cell to cell no more that 5* with a 20 load difference and 3* on a 10 load difference
Hope this helps you.
-Too much timing from 100 load through the rest of the load range
-At peak load you should be between 0* and 4* timing and end around 10* to 13* at 7k with your boost level and mods
- Timing should vary from cell to cell no more that 5* with a 20 load difference and 3* on a 10 load difference
Hope this helps you.