Tuning HELP

[SR20DAD]

Please forgive the newbie post and questions that have been asked a thousand times but answered two thousand different ways, I'm looking for help with learning the proper tuning sequence/method for my sons SR20DET (built bottom up) and what I'm looking for covers engine timing and idle settings;

Do you get the engine up to operating temp;

Disconnect the TPS - turn off - disconnect - turn on, rev to 2k - don't rev - get into timing mode - doesn't matter...?
Disconnect the IAVC - Don't disconnect...
Adjust the idle to 750 +-50 (using the screw on the IAVC)
I've read DO NOT adjust the stop screw by the throttle body - but what if some dip#$%^ already did that - how do you get it back to factory setting or acceptable setting?
Adjust the timing to 15 degrees (SR20DET)

There are lots of posts, and opinions, but nothing I see discusses the proper sequence/steps for the entire process so you don’t wind up tweaking this to only have an affect on that....

Is this procedure covered in the Factory Service Manual, if it is I would assume I need the 180SX manual that covers the SR20DET?

I’m looking to learn!

[cotbu]

if you have a stock ecu, then there is no tuning you car just runs like crap!
what we call getting the car to run properly is basic setup or properly setup.
base idle and timing is first, but only after you have oil and bled the coolant system. that should allow for proper temps to have been reached and cycled. So you know the cooling system is working correctly.


Disconnect the TPS - leave engine on - rev to 3k 3xs - you're in timing mode.
IAVC - Don't disconnect, adjust in timing mode 850 +-50 rpm
Adjust the timing to 15 degrees (SR20DET) while in timing mode

I've read DO NOT adjust the stop screw by the throttle body - but what if some dip#$%^ already did that - how do you get it back to factory setting or acceptable setting?

Adjust it closed visually then adjust the tps closed voltage. .45v

There are lots of posts, and opinions, but nothing I see discusses the proper sequence/steps for the entire process so you don’t wind up tweaking this to only have an affect on that....

This is life, sometimes you have to do things twice, you did say you wanted to learn.
for instance after you leave timing mode your idle might be high, 1000rpm well adjust it without going into timing mode. When you put the engine back into timing mode it should be 850rpm still.

Is this procedure covered in the Factory Service Manual, if it is I would assume I need the 180SX manual that covers the SR20DET?
I don't read Japanese.;)

[Kingtal0n]

you generally only disconnect the TPS when you go to set the ignition timing. At idle, factory ECU will bounce timing around to help steady idle speed, but only while the TPS is connected. So you yank TPS and set timing and that part is done.

For idle speed, adjust the IACV's air adjustment "bolt" (its probably a plastic screw in your unit). Adjust it fully warmed up engine, to desired speed (For stock camshaft engine usually 850rpm). Then drive the car, and re-adjust making only SMALL (1/4 turn) at a time, so that over the next couple days of driving you get it... perfect~

Make sure the coolant is connected to the throttle body because that is what brings the idle down when the engine warms up.