Tony just got one of the G-Tech performance meters. It uses G-force to calculate things like 0-60, cornering G's, acceleration G's, braking G's, 1/4 mile e.t. and speed, and horsepower and torque. Somehow it can detect the RPM through the cigarette lighter and the weight of the vehicle and a few other parameters are entered manually. We played around with it in his VW GTI a bit yesterday and the horsepower and torque looks very accurate. We'll try to get to Atlanta drag way to see how accurate the 1/4mile results compare. If it really works, it will be a valuable tool for any hot rodder.



I got some software and a cable for my laptop so I can monitor and record in real time what is going on with my '88 Firebird. It will be useful in 2 ways. For one, I need to diagnose a high idle. Second, it will give me the opportunity to learn about fuel injection and computer controlled timing on such a vehicle that is working before I do it with the truck. The usb interface cable and "good will donation" for the software only cost $90 bucks - far less than an equally capable scan tool.



There is all kinds of neat stuff out there.


Lawrenceville, GA

Those are pretty cool little devices.. It's surprising how accurate they are as well.. If you're looking for good test data on them I think SportCompactCar did a pretty involving test on them a few years ago.. The info might be in their tech archives on their website..

Dustin

Southern Oregon Y's Guy

http://www.facebook.com/?ref=h...

I just did my first data log, about 5 miles. It allows me to log all the data and i can play it back in real time at home so I can keep my eyes on the road. I had no idea how much goes on with fuel injection. It's neat! Now to figure out what it all means.


Lawrenceville, GA

I am about to buy Nokia 5800 or 5530 and go with racechrono.

It's easier to tune fuel injection sparkmap if you know ET.



http://www.racechrono.com/about/



BTW. They tested G-Tech on local magazine and result was very accurate. I remember it was +-2mph and +-0.2s on quarter mile or something.


Hyvinkää, FI

I solved the issue with the car! It was a vacuum leak. A leak as big as that was would have been obvious on a carbed engine. But nope. The fuel injection compensates for it so it runs great even with the vacuum leak. Since it idles higher, the vacuum reading is great. The map sensor registered about 26kpa which converts to about 22inhg. When I put my vacuum gauge on I got a reading of 21inhg.

It was easy to diagnose. With my laptop plugged into the car's computer, I saw that the idle air control was at 0 steps when idling. That means it was closed and not providing any air for the car to idle so the air had to be coming from another source. I verified that the iac was closed by blocking the passage with my finger and it was. So I got the can of carb cleaner.

It's a 2 barrel tbi unit and probably 1/6th of the gasket was missing from one of the bores. Now my city mileage is back to where it was. I can't believe I let it go on for so long. I assumed that since it is injected, it must be something more complicated.


Lawrenceville, GA