Give me the Good,Bad and Ugly on going with Classic FAST


May 31, 2006
Im getting a Classic FAST for my car and just wanting to know some peoples input on it??
it logs all the basics , but it doesnt allow for adding any other sensors to log things like oil or fuel pressure . no internal log but there was a seperate FAST logger available, so most log with a small laptop
most boxes have wideband control , makes tuning easier for any combo or change down the road.
most classic boxes versions were B2b with wideband and iac (30-122010) but there are also sequential (30-222310) and sequential with individual cylinder fuel and timing (30-222311)
the serial number on box tells the configuration, more bells and whistles the more the box cost

xfi works very similar to classic but allows sensor inputs to log things like fuel and oil pressures and with can bus can log egt channels, can run other ignitions and other types of sensors (good for more than a buick)
XFI 2.0 has more control of ...inputs , outputs , table parameters , injector flow, but you can do just fine on classic
They work fine and are less than half the cost of the new box's out there. To me they are a step up from stock. Just have less features than the new box's have. I have XFI 2.0 in both my cars now.
My friend's GN had the Classic FAST crap out on him on the highway about an hour from home. It dumped ridiculous amounts of fuel into the engine and amazingly it kept running. I think he used a full tank of gas in about 60 miles. When he stopped to get gas and figure out why it wasn't running right, he noticed raw fuel coming from the exhaust. Needless to say it got towed back home. He had engine damage from the oil being fuel washed. He upgraded to an XFI after that. My feeling is that I wouldn't buy a classic FAST for that reason. Don't hold me to it, but I'm pretty sure the drivers failed which caused this. If it were me (and I did), I'd spring for a new FAST XFI and call it a day. I'd hate to see you go thru what he did. He's lucky the car didn't catch fire and burn to the ground!
I have never heard of that happening . I guess it could but Classic is alot more affordable and I have a buddy with 3 GNs running classic.
I have never heard of that happening . I guess it could but Classic is alot more affordable and I have a buddy with 3 GNs running classic.
I never heard of it either. I'm not trashing FAST by any means, I love my XFI, but I saw this thread and thought I'd tell a cautionary tale of what happened to him. You'll kick yourself it it happens to you down the road. I'd go XFI... Just trying to help out a brother
what can happen is when the wideband sensor goes bad with classic you arent alerted to it failing have to connect and look for the sensor fault code ) and XFI is not immune as their sensors can fail with leaded fuel or contamination from antifreeze but XFI lets you know with the SES lamp that there is something to check .

when the sensor goes bad it drops voltage and will be read as 9.6AF which will command to pull fuel to meet air fuel ratio up to the negative limits set in the gain tables

quick fix is turn off closed loop and it should drive just fine if you worked your Ve tables close , then get a new calibrated sensor, and dial your tune in and limit the gain + and - adjustment

having a second standalone wideband running can help to see if the fast wideband sensor might be going bad
I'm sure youre right Pacecarta, but I'm 95% certain that he sent it back to FAST for analysis and they told him the box failed. I wish he could chime in here to speak for himself.
Thanks for the update. He is referring to my FAST. What happened to my box is the protection diode on the #3 injector failed, the FAST is programmed to default the injector to a wide open position. That explains the incredible amount of fuel used in a short period if time. The box I have has been repaired and is ready to use, I did upgrade to the new XFI, to get more features and be able to fine tune the tune, and log more information.
on OP question
one thing is classic can be 1/3 of xfi
if you have need for FAST you probably already have a scanmaster , translator/maf , powerlogger , wideband ... just selling off your old parts and ecm you can pay for a classic complete

and complete is
classic box
precision jump harness or casper adapter box (theres also an older fast track adapter that uses a gutted stock ecm)
com cable
usb adapter
working wideband sensor
3bar map (you may already have if you had a pl logging boost or razor alky)

and you will need to install a wideband bung into the downpipe and have a laptop perferably with XP or newer to run C-com Wp
c-com Wp program is available at downloads
I got the Classic for $625 shipped with everything but the 3bar map. I felt that was a good buy and It will do what I need it to do. Im just new to it.
My advice to the OP is if you have the money to upgrade to a XFI, do so. It is a better unit bar none. But, I have run my Classic FAST for years and have not had one problem. There is no down side to the Classic FAST. My car drives (like a stock GN, even with my big injectors) and performs flawlessly with this unit in my car. One day I probably will upgrade to the XFI because at my cars level, there are alot more features that can be fine tuned with the XFI. At your level, the benefits are less, with smaller injectors etc.
If I was you I would get in contact with the Cal Hartline. There is nobody better to assist you in your needs, and he will not steer you in the wrong direction to make a sale. I trust this guy whole heartedly. His has had multiple opportunities to sale me something I didn't need, but was always up front, gave me options, along with his choice based on my budget and went from there. If you go through him to buy a new or used unit, you will also receive something far greater then the unit you buy, you would receive his customer support and start up tune that will get you started. IMO, the buck starts and stops with Cal where these engine managements are concerned. You would be losing out if you went any other way.............. Just my 2 cents.
I had already bought it tho. I still need the start up tune and disc? Im getting my o2 bung and 3bar map this week.