AFR tuning questions unique to my situation.

[dcskater180]

I've spent a decent amount of time on searching this and not finding anything that is super helpful for me. I originally planned on just saving for link but my spun bearing is costing me all my pennies 750$ on machining no bearings pistons gaskets etc and im a college student so my question is whats the best way to keep AFR at a healthy level I dont have a WB o2 so im not sure its bad but the guy i bought it from has this dimmer like switch/know that is shoved behind my radio and it adjusts my AFR but the car only runs with it all the way right so i have a hard time thinking its correct. Also the knock LED which i know is useless but is there shows lots of knock if i turn it on a night my interior just flashes red . So do you think MAFT GM MAF and a wideband would take care of this Link is too expensive for me and i would like to know if I am destroying my car or not.

 

[Twinturbo120]

How do you know that switch adjusts the afr if you don't have a wb? Either way, just save your lunch money and get link. It's worth it.

 

[clipto]

Gm maf is garbage. Best is 2g or evo maf. And for a little more just do speed density. Save up wideband and link and your set. Sell some old Xbox crap around the house you'll get it eventually.
Do it right the first time so u don't have headaches.

 

[dcskater180]

Im well aware that I need a wideband that's my first purchase after I get my engine together. Is there anyway to control AFR without changing MAF

 

[Breezio69]

Safc... but by the time you get that either new (around 400) or used (usually around $200, sometimes you see older models for 100-150) you've already spent half of link or almost bought link.

I use an safc, had I not gotten it for $60 I wouldn't be using it at all. I'm getting link by selling a bunch of misc crap I have laying around for cars and whatnot, because the safc is very primitave and I feel I can't do things in my tune that actually help the car... last timing reading I got went to 2* wot at only 4.5k rpms, thats not right.... I can't adjust anything on the safc to compensate without messing up my entire fuel trims and making it run super rich or super lean. Needless to say, tuning with an safc hasn't been fun for me because I don't even dare go into boost.

But that's your other option from link, take my experience with it or leave it...

 

[Breezio69]

Edit: double post

 

[PieEyedPiper]

I want to know more about this knob behind the radio that adjusts your air fuel ratio, but the car only runs with it turned all the way up.
$10 says its nothing of the sort - but it's obviously something. Maybe some wacky pot mod.

And this thing is just a random knob hooked up to some wires? No identifying markings of any kind, or an associated box?

Also, a red knock sensor light? That constantly blinks when the car is on?

It's time to find out what is actually in this car. Bust out the camera.

 

[clipto]

You should take pics of your engine bay and all these things in your car so we can see them.

 

[98zx23369]

I agree with PieEyedPiper. I wanna see this thing.

 

[Breezio69]

Its most likely some flee bay crap, I work with a guy that drives the most ghettoed out lancer oz with just about every ebay chip and resistor for this and that... I finally broke it down do him and told him he's wasted countless dollars on all that "gain 15hp chip" crap. But he still doesn't believe me and thinks his lancer is an evo with all this plug and play garbage.

This sounds like the same stuff unfortunately.

 

[FLASH1970]

I've spent a decent amount of time on searching this and not finding anything that is super helpful for me. I originally planned on just saving for link but my spun bearing is costing me all my pennies 750$ on machining no bearings pistons gaskets etc and im a college student so my question is whats the best way to keep AFR at a healthy level I dont have a WB o2 so im not sure its bad but the guy i bought it from has this dimmer like switch/know that is shoved behind my radio and it adjusts my AFR but the car only runs with it all the way right so i have a hard time thinking its correct. Also the knock LED which i know is useless but is there shows lots of knock if i turn it on a night my interior just flashes red . So do you think MAFT GM MAF and a wideband would take care of this Link is too expensive for me and i would like to know if I am destroying my car or not.

Step one, find a new college. The college you are attending is not teaching you spelling or grammar or how to read. You agreed to forum rules when you signed up that included these things. We all make mistakes but please make an effort. It makes posts much easier to read and makes people more inclined to help you.

Ok, I read your profile and your rebuild is consisting of H Beams and forged pistons. Forged internals aren't required unless you're pushing a lot of HP. If your HP goals are 400whp or less, a rebuild with stock internals, maybe ARP rod bolts and ARP head studs is all that is required for a reliable fun car as long as the tune is good. That'll save you a bunch of money right there. To run a good AFR without having a Wideband or a way to tune is to run the factory MAS, with stock injectors, on the stock boost level. The 190 pump you have will be fine on the factory fuel pressure regulator.

If you had a way to datalog and tune, you could get your idle and cruising dialed in by logging your fuel trims and seeing if the ECU adds or subtracts fuel. Getting those in check does not require a wideband.

 

[jed344]

Ecm link my buddy has a SAFC II and a old VENOM box laying around from back in the day we threw into his car just for fun to see what we could do with it and watch his Wide band and link to see what they really do and honestly it was kinda pathetic... They are old school technology.

 

[Mischif]

The switch is probably a potentiometer that could be wired into the o2, air temp, or coolant temp sensor. Its an extremely "ghetto" way to attempt to manipulate your a/f ratios. It would be wise to trace the wiring for it and remove it.