So it looks like I’m the new owner of a st165 all trac.
It has a few upgrades bit no management, it has an aftermarket exhaust manifold and a bigger turbo, a full exhaust, a front mount, an apexi air filter/adapter. When I drove it, it felt lean (imagine that). What can I do that's a cost effective way to get it tuned without spending all out doors. Obviously a haltech, etc. would be ideal, but I’m trying to just get it safe until I can go nuts on a build. I’m fully aware that you gotta pay to play, just wanting some cost effective options. Maybe some old school piggyback with dials or something and some oem injectors from a supra or something weird lol? Thanks!
Throw a wideband in it so you can see what it is doing, first step. No sense making changes until you know what changes you need to make.
Are you interested in keeping the airflow meter?
Pretty much nothing exists for these. Even replacement parts will be second hand. Get used to that.
Not looking for free.
wideband is waiting for the car to come. Talking to a guy about a apexi safc for 3sgte. If it's close, I might be able to fill in the lower end with a air flow door mod (let the door open easier) and a fpr or something.
You probably want to make the air door spring STIFFER, not softer. Making the spring weaker will make it run richer until the point where the door is wide open, at which point it is no longer measuring airflow. You are reducing the sensor's range by making the spring softer. If you make the spring stiffer, yes you will be leaning it as an immediate effect, BUT you will also be increasing its total span of measurement, and then you can make up the leanness by increasing injector size or raising fuel pressure.
Big turbo and uncorkedness mean the airflow meter is probably running out of range. That is why my gut reaction is to stiffen the spring so the range is increased.
Stiffer to lean out and add resolution if you add fuel by bigger injectors right? If the added airflow makes it open, then its right to open, telling the ecu that there's more flow (correctly). Once its at full open then its maxed out for that area of the map unless you change something to add fuel.
anyone know of bigger injectors that are plug and play? Maybe mkiii supra or somethin? (Edit: nope same injectors as a mkiii turbo supra stock, see link in my comment below).
If you just need to go a hair leaner wouldn't an adjustable fuel pressure regulator get you there?
I would start with a wideband and EGT sensor, next would be a AFPR with boost sense. Tou might need a stand alone boost controller to keep spikes down.
Have fun, good cars.
Robbie (Forum Supporter) said:
If you just need to go a hair leaner wouldn't an adjustable fuel pressure regulator get you there?
Dont need leaner with a big turbo and a full exhaust on stock management. The only thing that would make me need to lean it out a bit would be if I upgraded the injectors without a standalone. Then id need to trick it into leaning out a bit when it's off boost.
I put standalone on two of these in the mid oughts and it wasn't too hard. MS2/microsquirt may be about what it costs to get an afc working well these days.
