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lplott
June 5th, 2006, 06:33 AM
:notacrook: Coolant Temp Spark Multiplier B5956 is suppose to be set to 1 where ever you want boost retard active. My B5956 only goes up to 4000rpm, is this a problem, does it assume 1 above 4000, do i need to add columns in the RPM to go up to 6500?

thanks
Lonnie

lplott
June 19th, 2006, 04:39 AM
ttt

Could you guys that wrote the custom OS tutorial answer this question?

thanks,
Lonnie

hpcubed
June 26th, 2006, 01:47 PM
Ttt

Delco
June 26th, 2006, 06:10 PM
No it holds the same value from 4000 up . That is a std GM table and not a custom operating system table so unfortunately you are stuck with what is there.

That table is also not referenced to boost but ECT

The table you want for boost retard is A0010

lplott
July 5th, 2006, 04:24 AM
Yes Delco, I agree with you. But if I understand correctly, B5956 has to be set to "1" where ever you want A0010 to be used to Retard Spark using ECT as the reference.

Do I understand B5956 correctly?

Thanks for the input.
Lonnie

GMPX
July 8th, 2006, 02:50 AM
The reason the factor must be set to 1 is because the boost retard values are actually calculated within the ECT spark routine. That might sound dumb, but it was the easiest way to implement another spark modifier.

So, if the factor value in the ECT spark table is only 0.5 then your boost retard value will be HALF what you command. If the factor is 0 then the boost retard table will have no effect. So, that is why is is necessary to ensure the factor in the ECT table is at 1.0 anytime you want the boost retard to have any effect.
Looking at a Camaro B5956 table, any time the engine is at operating temp the value is 1.0 anyway for the entire RPM range.
Thanks Delco for answering the other question, the Factor from 4000RPM up remains the same all the way to 8000RPM or higher.

Cheers,
Ross