1991-1992 B13 SR20DE Fuel and Timing Maps

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UNISA JECS
 

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1991-1992 B13 SR20DE Fuel and Timing Maps

Post by UNISA JECS »

Hi Matt its been a while since I been on here, but I wanted to let you know or ask why is it that both the the timing and fuel maps have the same values?

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Last edited by UNISA JECS on Tue Dec 25, 2012 9:40 am, edited 1 time in total.
UNISA JECS
 

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Re: 1991-1992 Fuel and Timing Maps

Post by UNISA JECS »

Actually after browsing aorund it seems atleast all the SR20DE maps or ADR files have this problem.........
UNISA JECS
 

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Re: 1991-1992 B13 SR20DE Fuel and Timing Maps

Post by UNISA JECS »

HI Matt can I get an answer to this I know before it wasnt like this, is that a problem in the address file not looking up this correctly? Thanks
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Re: 1991-1992 B13 SR20DE Fuel and Timing Maps

Post by Matt »

Its been christmas holidays, so havent been around. So I could not look at this until getting back

Okay an easy way to tell if the address files are correct is look at the addresses being referenced in the address file (or in the software)

Modifying first column/bottom row of these maps

High fuel 0100
Knock fuel 0E00
High fire 0D00
Knock fire 0800

This confirms the address file mapping is correct

As for the base address file used:
HIGH_FUEL,&H0100,16,16,256,1,High octane Fuel map
REG_FUEL,&H0E00,16,16,256,1,Low octane Fuel map
TP_SCALE_FUEL,&H00F0,16,1,16,1,TP scale (Fuel)
RPM_SCALE_FUEL,&H00E0,16,1,16,50,RPM scale (Fuel)

#HIGH/LOW octane Ignition time map and scalers
HIGH_FIRE,&H0D00,16,16,256,1,High octane Ignition time
REG_FIRE,&H0800,16,16,256,1,Low octane Ignition time
TP_SCALE_FIRE,&H0490,16,1,16,1,TP scale (Ignition time)
RPM_SCALE_FIRE,&H0480,16,1,16,50,RPM scale (Ignition time)
Matches the above. The fuel and timing maps can be modified separately. It is likely on SR20DE models since it is NA that the fuel and timing uses the same maps

You will notice using an S13 SR20DET BIN file (compatible with fuel/timing map entries with the B13 SR20DE address file) that they display different maps. Not an issue
UNISA JECS
 

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Re: 1991-1992 B13 SR20DE Fuel and Timing Maps

Post by UNISA JECS »

Thanks Matt I guess I was just used to tunning my KA24DE(T) that had very different knock vs non-knock maps so my next question is since these maps are the same what does the ECU do when the engine detects knock then if the maps from the factory are the same? Nothing? or do you happen to know what they do?
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Re: 1991-1992 B13 SR20DE Fuel and Timing Maps

Post by Matt »

It probably will still switch maps to knock after continuous knock

However the ECU will pull timing also on knock counts so this will still happen even if maps are the same

Since these are SR20DE models in the US there are no high/regular octane fuel tuning like for turbo or Japanese models
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