IAT trick for nitrous (timing retard)

[FiFdYnUtZ]

hey guys, i am just looking for some clarification on the trick for retarding timing on nitrous by unplugging the IAT and altering the coldest cells in the table shown below to show the desired timing...is this the correct table? and which cells do i change..and when i change them do i put -# for how much i want taken out or do i put my desired timing? sorry for all the questions i would just go out and try it but we just got 12+in of snow here and the car is in storage, just wanna get my ducks in a row before i tackle it..thanks!

[KFZ)^]

Take a look at this writeup:

http://www.robertsnitrousservice.com...ullwriteup.htm

[Mep_q8]

it depends where ur iat sensor would be placed... if u could relocate it, then hey, no need for timing retads..

[FiFdYnUtZ]

its in the stock location, what do you mean no need for retarding if its relocated?

thanks for the link KFZ but im looking to have a way to drop timing for spray without uploading a different nitrous tune, i already have a tune with dropped timing...just need a quick way to switch (just pulling the IAT sensor)

[FiFdYnUtZ]

and my car is lc1 wideband tuned in speed density if that matters...

[KFZ)^]

Sorry, that link was for dry shots.
Here's another stab at it:
http://www.ls1tech.com/forums/nitrou...tor-trick.html

[FiFdYnUtZ]

hmm those guys are putting a resistor and switch to it, that would be nicer then just pulling it, but it appears to be a bit over my head at the moment lol..i'll keep reading on it..thanks KFZ!

any more info on the simpler way of just pulling the iat?

[KFZ)^]

Well I don't know what car/engine you have, so that might help.

I could assume that you have a car with a separate IAT, but 2001+ Gen3 LSx's have IAT's integrated into the MAF, AFAIK. That last link shows pinouts for the different MAFs.

The IAT tables in the Editor for LSx are:

Engine->Spark Control->Spark Advance->IAT Spark->Base (timing adder table)

AND

Engine->Spark Control->Spark Advance->IAT Spark->Mult (used to enable/disable the spark adder)

EDIT: YEAH YOU'RE IN THE RIGHT TABLE!
What do you want to know? Basic rule is -2 degrees for every 50hp of the N2O shot...

Seems like you already know what to do!

[Mep_q8]

its in the stock location, what do you mean no need for retarding if its relocated?

as in a timing retard module that you would have to buy that will reduce timing when your on the gas.. (MSD, NX, etc)

[FiFdYnUtZ]

im wondering which cells i change and what do i put in them ( on the table i posted)? i want to run 20degrees total timing when on the spray (i run 25-27 NA) and if i change those cells, all i have to do is unplug the iat? thanks so far guys!

[slammin86]

hey guys, i am just looking for some clarification on the trick for retarding timing on nitrous by unplugging the IAT and altering the coldest cells in the table shown below to show the desired timing...is this the correct table? and which cells do i change..and when i change them do i put -# for how much i want taken out or do i put my desired timing? sorry for all the questions i would just go out and try it but we just got 12+in of snow here and the car is in storage, just wanna get my ducks in a row before i tackle it..thanks!

Yes you have the right table. Unplug your iat and log to see what temp it is actually at. Then take that whole column and the ones next to it and subtract out whatever you wanna pull.

OR...

Wire up a relay with one of the iat sensor wires on it, and have the relay break the contact of the wire whenever the system is activated

OR...


Wire up a relay with a resistor to trick the ecu into thinking the iat is at the hot side of the table.