STEEL

Well yall, fuel injection has some awesome advantages, and yet I find I know NOTHING about it. I have a 1991 RS with the 305 TBI, I would like to learn how to tweak the fuel injection to get slightly better fuel economy, or tune it if I were to change something on the engine, such as a cam shaft.

All in all, I want to learn.

I assume that adjusting all FI is basicly the same, but the newer the system, the more options and more possibilitys, making TBI and CFI the simplest to adjust for a beginer, am I kinda right?

What is required to start tweaking? How much money is required to get started learning? I know in some movies the ricers actauly have an air fuel mixure guege (SP?), is that something I need, or does the O2 sensor tell the computer that while I am programing?

For now, I want to start for stuper n00b. Teach me master

Ronny

iTrader: (1)

Read the stickies in DIY prom. Lots of info there. I dont think TBI simplest to adjust. I would think a MAF system may be considerably easier as it measures air flow at TB with a mass air flow sensor accurately. Maybe someone wll disagree? TBI is speed density which determines airflow by rpm/cid/vac sensors.

NB02 just toggles A/F over a desired ratio for the cat convet. keeps A/F there regardless of air temp. keeps emishions in line and gives good mileage. A WB reports real A/F. WB is very accurate. A tuning tool. NB is just a sensor and not really a tuning tool. Just feeds info to ECU. A WB is not necessary to tune but helpfull.

A cam? Now you need to burn a chip or have aftermarket do for you by mail.

STEEL

O.o

Let me see if I understand, TBI trying to adjust based on what the computer thinks is the air flow based on RPM, Vacuum, and other influences, but it doesn't have a MAF sensor....

I really just want to start with the basics. I dont plan on keeping this car forever, just basicly long enough for me to re-do the interior and then sell it. While I have it, I thought I could take this chance to learn the simple basics of FI.

Someday I want to get my hands on a second gen and addapt a FI system to it, in which case I will need a LOT more knowlage than I have now.

Ronny

iTrader: (1)

See my edit. I sent too soon. You are correct. MAF has a sensor running over top of TB. A thin wire that is heated and senses airflow. Now I read some owners that have MAF convert to speed density. Not sure why but I think the MAF sensor is problematic or cannot read large amount of airflow(heavy mods).

STEEL

Ok, there are a lot of abbreviations in your first post that lost me, if you could go back and clarify i would really appreciate it.

So before I try to learn by buying all the stuff to plug a lap top in and REALLY screwing it up, how hard is it to just stick a power commander on and start playing with A/F ratios?

At least then I would feel like I am learning something, and if I dont like the changes I can pull it back off and it will revert back to stock tune.

The objective would be to try and squeeze a few more MPG through it, after all, i use the car for Pizza Delivery.

Ronny

iTrader: (1)

TBI throttle boby injection
MAF mass air flow
RPM rev per min CID cube inch displace VAC vacuum
NB narrow band 02 sensor toggles(rich lean) at 14.7 or 14.3 for ethanol WB wide band sensor reports actual A/F very accurately.

I believe you car is getting best mileage available as stock. way to improve is a tune up.

ownor

iTrader: (5)

just curious, what MPG are you getting with the T5, open element and some exhaust work done?

STEEL

Lol, exhuast work.... Someone eliminated the pipe that goes from the cat to the muffler, so the muffler is still there, but no exahust gets to it.

I dont actually know the MPG yet, just got the car about a month ago, but i have not been able to drive because of a motorcycle wreck, still on the first tank of gas.

Its not my first LO3 though, i had a car that was exactly the same about a year ago, then dropped a 383 in, then sold the car because I was getting 7mpg