if you want the most, standalone. in my mind, piggybacking is a way of getting by till you can afford a standalone.

standalone allows you too completely tune every aspect of your fuel and ignition (depending on product). piggy backing is mostly "fooling" a few sensors to input false signals to the computer, so you can bypass stock restrictions, to a certain point (this still depends on what product you purchase).

mind you, standalone learning curves are steep, and most of the time not very inexpensive. u have to be patient, careful and willing to put in the work.

ive seen and read about several mk3's and 7m powered vehicles cracking the 350 and even 400 barrier on the stock ecu's. past that im unsure how far the stock ecu would be effective, and the afore mentioned cars were pretty heavily modded aside from the ecu.

someone else undoubtedly has more experience and information on this particular area.

It all depends what u are willing to do with the car if ur making fast as a drag, freeway killer or drift monster. The way i did it was i bulit the motor first with out the turbo. Just engine and then i bulit the fuel system, the reason i started with the fuel system is that everyone only bulids it for the power that there making. I built the fuel system as i was runnig a 1000hp car.

The biggest thing you have to worry about is the fuel, ecu can be reflashed and reprogramed it depends on ur tunner and shop ive seen these cars run around 500hp with a little reprograming. So the truth is how much money u have to spend and the dyno, or tunner shop u have.

A big bulid takes a while theres a lot to do and a lot of R&D belive me it wont come over night it took me 3years to get it like this and now its a part down.

How can you do that with an ECU that has no flash memory?

:rofl:

but i understand where hes comin from. i try to listen to what ppl mean vs what they say, lol.