View Single Post
      04-06-2009, 12:32 AM   #91
First Lieutenant
psu139's Avatar

Drives: 335i Sedan
Join Date: Apr 2007
Location: Pace, Fl

iTrader: (1)

Originally Posted by Bob Long View Post
My car with just bolt ons and race gas made ~410 whp.

Well I think when you spend top dollar for a turbo kit it should look and utilize the majority of the OEM system which the piggyback is not, piggybacks are kind of old fashioned. Also a inherent side effect of a piggybacks as is that it only alters or tries to simulate the signal the ECU sees and never changes the actual programming, just attempts to manipulate it. The manipulation can only go so far as most piggybacks alter just one (at most a handful) of signals at certain RPM points and not necessarily the array of load maps the ECU relies on. With today’s ECU’s, signal modifications confuse the ECU’s learning mode often resulting in poor drivability. Also, direct changes in one signal may also trigger indirect changes elsewhere which can lead to undesired consequences. If you have the technical ability to properly adjust the factory ECU, there is no reason to falsify its input signals with a piggyback.
what tune are you running?