I was wondering how people tune the TBI. You can burn PROMS all day, but how are you going to know if you are making progress? I doubt you can go by SOTP. I know with a carb you can just hook up a vacuum gauge to it and when you get the max pressure you are there. Since TBI is basically a computer version of a carb(well actually the Q jet it but you get my point) Is this the way to do it?

 

EFI stands for electronic blah blah blah, use a scan tool and it tells the whole story. Carb has very little in common with TBI except for the fact that they're both wet-flow intake designs (hence the manifold sharing with adaptor plates). EFI is very sensitive to changes with eprom burning and you CAN feel a difference. Just like you can feel a difference with adjustments made with changing jets and dissy weights/base timing, you can feel it in the eprom tuning. It's probably easier with EFI because when you make a change you know where that change was made, say for example giving a few more degrees between 2500 adn 3000rpm. A good running EFI system takes into consideration most weather conditions (temp and pressure) and so you can feel the difference more reliably compared to a carb being tuned in cold weather and tested in warm humid weather. Winaldl lets you use a computer and you can watch all the information that the ecm is doing. I've just recently modified my eprom to spit out the final spark advance and this gives me an even bigger picture on what's going on.
Nobody should tune without winaldl UNLESS they're at the track and watch the mph betting better or worse .
Pablo tunes without a scanner or software but he's also pretty crazy and winaldl wasn't around when he got started with the diy-eprom.

 

One way or another you need a stop watch.
A G-Teck is one answer, or building your own little in car timer.
I build one that tuns of the VSS.
Ignores the first 2 tire revolutions, and then counts 100 tire revolutions.

SOTP just doesn't work.
Too much timing and too rich always feels better, but is slower.

 

Where do I pick up this Winaldl? Ramchargers? and how do you attach it to the car?

 

As far as tuning a TBI motor (350 probably) I saw JET engineering offers a "six pack" deal with 6 different configurations wrapped into one chip - its designed for trucks w/overdrive but i'm wondering if it'd work in a camaro...its the same motor/tranny right?


TP

 

grumpy, can you give us more info on teh timer you made? that sounds like a cool idea. any diagrams or anything you coudl share woudl be great. thanks.

later
tim

 

Tim, I already asked, he doesn't have the plans and doesn't plan on taking the unit apart unless it breaks. Oh well, guess we'll just have to design one ourselves.
Jonas (winaldl author) has a project working up that will record performance with a laptop more accuratly than the g-tech. Only catch is there is one wire that needs to be run (oh NO, not a wire! lol).
I might design my own if I find the time imbetween classes. I'd rather use a laptop. They're an accurate readout and can record multiple inputs from your vehicle speed, rpm, and distance traveled (from calculations from tire diameter and mph over time). It's really not that complicated. I just gotta figure a way to use the parallel port for the inputs. I've already figured out how to program and control outputs from the parallel port, now if only I had spent more time on the inputs , proof that rushing through good reads is a big no no.
The reason I'd like to use the parallel port is because I've got winaldl on the only serial port (laptop only has 1). Maybe if I felt like be ambitious I'd do something with the confounded IR port that has absolutely no use as of right now. Correction, that's if I win the lotto OR somebody directs me to some good sources for how to program for the IR port AND build the hardware to transmit a signal from speedo and engine rpm.