I thought it might be helpful to have a general thread in the 991 Turbo section on ways to increase horsepower and torque (e.g., exhaust systems, powerkits, etc.).

I'll get the discussion going by asking what folks' thoughts are on the GIAC software versus Techart power kit. Which is the better way to go? And will either modification void the factory warranty? For reference, here are the links:

http://www.giacusa.com/news_and_medi...ews.php?id=169

http://www.techart.de/en/techart-sho...-i/engine.html

 

I am planning to put on the IPD Plenum and the GIAC tune. I got quotes from Park Place which sold me the car and from blackjackspeedshop in San Antonio. The latter had a better price on the GIAC part and is closer to me. Park Place has told me they don't have a warranty issue with the stuff they do to the car, but the dealership here in Austin is definitely mod unfriendly and won't deal with modded cars.

I use Vbox to measure quarter mile results with my cars and I have measured my car with the Vbox already in several different locations and temperature / DA conditions. I already have the FVD exhaust with the high flow cats so don't have a bone stock baseline but I like the numbers I have so far. I am looking forward to pulling the trigger on the other mods soon.

 

wrs -- I replied over on RL, as well, but I'll be anxious to hear your thoughts on the GIAC tune. Please update as you can.

 

I will do that. Just not sure when I am going to put the tune on. My M5 is in the shop this weekend with a fuel issue we think. It might be the fuel pump. I am thinking about selling it but I have some more testing I wanted to do with it in cooler weather. See how fast it really is with the mods I made to it in cooler weather.

 

Curious on this as well. I am always hesitant to have my ecu locked to some fixed tune that I have no ability to retune for more precise environmental inputs as well as to remove completely for dealer visit. The tech art piece gets nice reviews, but $6k for 40-75 whp seems tad on high side. I am hopeful that Cobb or Ecutek etc will release personal tuner solution with the ability to log and retune to maximize gains.

I am also still interested to see if possible to upgrade injectors/pump and run e85

 

Once you tune the ECU, even flashing it back to stock does not fool the dealer if they plug their diagnostics into your OBDII port. Your car will get a code in the dealer's computer (and that of any other service department, as well as PNA) telling them that the ECU has been altered. If you want to flash, assume the risk. Not trying to dissuade anyone, because I am strongly considering a GIAC tune myself, but I appreciate the risk and do it with eyes wide open. If I am wrong, someone will point that out.

 

I agree with the dealer being able to see that an ecu may have been tuned. but most "cool" perse dealers may look past that and warranty and issue that may not have been a direct result of any tuning.

As for the GIAC, again the reviews are decent. But you are totally stuck with canned tunes and no way to customize to your mods, available fuel, elevation etc. Would also like the ability to have oem/mid/kill mode tunes that I can select from quickly without the need to break out a handheld switcher unit

 

Agree. Dealers will often look the other way. It is when the regional rep has to show up for a warranty repair and PNA takes over that the problems will be encountered. I don't doubt that my dealer, or any dealer that actually sells the software, will do their best to honor the warranty. Unhappy customers don't come back to buy more cars.

 

I would definitely do a piggy back if it could be upgradable with custom etunes. Don't want to be locked to one tune fits all