boostisgood
Member
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- 1988 FC3S TII
My questions is this. How the hell is a bike or traffic cop gonna know if I dont have th stock ecu or a piggy back in my car ? They gonna issue cops 4k scantools ? Not cost effective if you ask me. 

boostisgood said:My questions is this. How the hell is a bike or traffic cop gonna know if I dont have th stock ecu or a piggy back in my car ? They gonna issue cops 4k scantools ? Not cost effective if you ask me.![]()
Bigg Tim said:That's what I was told by a guy who runs it. You have to datalog then view the datalog and then make changes. You can't make changes while driving the car real time. Meaning, you can't view/change fuel or timing live,only viaa datalog, Is that wrong? If it is, then I apologize for saying incorrect info, that is just what I have been told. Like I stated earlier, I have not used either.
wicked said:piggy backs all comply so you can get away with useing a HALTECH,MPI,UNI-CHIP,DSM AFC,and such.but only if retaining your stock ECU.
ion332 said:Nah, its been coming out that all you need to do is rev the car with the Haltech, unichip, AFC, etc and it will throw a fault.
So, although its a better choice than a full standalone for stealth, its not any guarantee. At idle, sure, it will show a bone stock ecu.
Problem is, for high hp apps, the piggyback stuff can't make radical enough changes to deal with it. And, some of the piggybacks still cause a cel.
Unless you can stim the stock ECU to get its exact inputs it wants, its still going to raise an eyebrow or two amongst the po-po.
The cops aren't stupid as you would think, many places actually have streetracing taskforces and some of these guys were gearheads first before they became police.
Bigg Tim said:Not all entirely true. There have been piggyback users that made over 300whp at 15psi, just like with a standalone. And my PB doesn't look any different when hooked to a scan tool when you rev it. It all depends on the unit and the tune.
spacemonkey said:Of course in the future most likely everythign will be "piggyback" style. even standalones. ECU are just so complicated like the new BMW M5 ECu and RX8. Now you have a factory ECU controlling things like AC and you have cars with new technology like electronic steering and direct injection. So that makes it almost impossible to remove the ECU becasue it controls so much.
ion332 said:Well, thats where you run into a problem...
Some of the newer ECUS know when the injectors, ignition, and IAC are disconnected and they go apeshit and do things like not allow you to turn on the AC, run the fans all the time, or, in the case of some BMWs, they just won't start.
So, even in piggyback mode you need to have inputs that are going to allow you to give the ecu the correct feedback so it doesn't have any issues.
So, in some cases you can't get between the ecu and the injectors or the ecu will fault.
IN some cases, you can't get between the ign and the ecu or it will fault.