TBI o2 open loop vs tune

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Dropped88

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I have a 1992 454 with the single wire O2 sensor and I know you can upgrade to a 3 wire so the o2 stays efficient at idle.

But if i only change the sensor will it keep counts high enough to stay closed loop or is it programmed to automatically go open whicj is rich on O2 reading, doesn't smell rich.

I have no driveability issues everything looks good on the scan tool and knowledge from LS tuning, the open loop idle can really effect fuel economy.

And I know a 454 is not a gas sipper but I fell if I can stay closed loop idle it's help gas mileage.

Also is a mild chip good for any improvement if I need tuned for closed loop idle. Truck runs good so trying everything to no rip it out for an LS or anything else I'm able to tune myself.


Edit. I have upgraded fuel pump to vortec pump for a fuel starvation under WOT. And for possible future engine swap didn't want to do it twice. So can I run an 18lb spring without tune or is that to much pressure for a stock tune.

I ask all this from a bad experience with tbichips.com many years ago
 
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PlayingWithTBI

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But if i only change the sensor will it keep counts high enough to stay closed loop or is it programmed to automatically go open whicj is rich on O2 reading, doesn't smell rich.
IDK if yours is or is not set up for CL at idle. You'll have to look at the .bin to see. Yes, a 3 wire will help if you do have CL at idle.

Also is a mild chip good for any improvement if I need tuned for closed loop idle. Truck runs good so trying everything to no rip it out for an LS or anything else I'm able to tune myself.
It's always better to drive around, data log, tune, rinse and repeat.

So can I run an 18lb spring without tune or is that to much pressure for a stock tune.
It will need to be tuned or it'll be pig rich unless you added other go fast parts.
I ask all this from a bad experience with tbichips.com many years ago
Yep, me too. That's what started my venture into tuning.

What trans do you have? Is it computer controlled? If not, the EBL Flash-II with a WBO2 will do everything you wanna do. It has 8 flash banks which you can tune with TunerPro RT, and flash with his software. It even comes with the cable to data log and flash.

www.dynamicefi.com/EBL_Flash.php
 

Dropped88

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@PlayingWithTBI I have the 454 and 4l80e and I appreciate the info and I'm gonna try a 3 wire o2 it's a cheap enough gamble.

Next thing is I gave up obd I for simplicity of obd II tuning with hptuners. So if I was to get into tuning obd I stuff.
What am I looking at getting into cause looking into the early stuff is confusing with the multiple pieces to tune.

For example can I tune TBI on the fly or do you pull the chip reflash it reinstall and just repeat till it's fine tuned and what kind of money for a tuning setup to do TBI.

I can do all the research but would like some guidance on what hardware I need to start tuning

Edit: also TBI is no powerhouse but can you get enough out of a tune to make a noticeable difference
 
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PlayingWithTBI

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I have the 454 and 4l80e and I appreciate the info and I'm gonna try a 3 wire o2 it's a cheap enough gamble.
I thought so. Then the EBL would have to run with your PCM, not the best way to go. Here's the 3 wire setup I got, ACDELCO AFS74 and Michigan Motor Sports 22300
www.amazon.com/s?k=AFS74&crid=23QG66NA7LI5A&sprefix=afs74%2Caps%2C1019&ref=nb_sb_noss_1

For example can I tune TBI on the fly or do you pull the chip reflash it reinstall and just repeat till it's fine tuned and what kind of money for a tuning setup to do TBI.
You can do either, tune on the fly with an emulator or set your PCM up for a flash chip (such as the SST 27SF512) using a laptop and TunerPro RT (the RT version can data log while the plain TunerPro doesn't). You'll need an ALDL cable too.

TunerPro RT is free with a suggested contribution.
www.tunerpro.net/

Moates.net has emulators and the Burn2 for flashing and reading chips. It looks like he discontinued some of them but, the APU1 package is still available. Surf through the site to see what's available.

Here's the ALDL cable
www.aldlcable.com/

Here's some definitions with which you may want to familiarize yourself.
www.gearhead-efi.com/gm-ecm-pcm-conversion/efi-dictionary.html

Read through these sites for some good info, HTH :waytogo:
Edit: also TBI is no powerhouse but can you get enough out of a tune to make a noticeable difference
Yes, GM left a lot on the table with conservative SA tables and stuff like PE and AE
 

Dropped88

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Alright I'll go through that and if I have any questions. If you don't mind me asking I'll post them up
 

Dropped88

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Emailed moates and APU1 is Discontinued so the option he gave me was.

GP1 kit chip adapter and chips
BURN2 chip programmer
ALDU1+CABL1 logging cable.

After work I will do some research but do you have any experience with any of the above items through moates.

Or maybe know someone with a APU1 that they would sell.
 

PlayingWithTBI

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After work I will do some research but do you have any experience with any of the above items through moates.

Or maybe know someone with a APU1 that they would sell.
Similar to what Moates suggested - I have the Burn2 I used to flash chips for my 7747 ECM with TunerPro RT. I had it modified (by Dave w, OldSchoolEFI on Gearhead-EFI) with a 28 pin ZIF (Zero Insertion Force) socket. Then I data logged, emailed my log to Dave, he'd tune it and email the new .bin back to me, I'd flash one of my 27SF512 chips, rinse and repeat. Note: this was after my bad experience with tbichips mail order crap. After getting my INT and BLM dialed in, dave and I agreed the 7747 was just too slow (160 baud rate) and has too small tables (only going up to 3600RPM IIRC, too lazy to look it up right now), so I went to the faster EBL (8192 baud) with bigger tables (up to 6500 RPM) and a WBO2.

I have not tried the APU1 or any other emulation package, maybe someone else will talk to this?

Every once in a while I see some hardware for sale on www.GearHead-EFI.com HTH
 
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