I am VERY interested in speaking with someone at APR about upgrading my 991.2. I have reached out a number of times but have not been able to get responses. Unfortunately the questions I am asking require someone familiar with the platform so reaching an engineer or technical sales person is needed. I would be happy to pay for the 10 min they spend for the call and the questions are well developed and not vague.

1.) E85 Tune Details - Can the tunes be switched, is Flexfuel possible, do the plugs need to be changed, does the low pressure pump need to be modified....
2.) Tial Turbo Tuning - Can they provide a tune for this or support my local shop with a custom tune, are the gains perceivable on a GTS/X51
3.) Tune Switching - Needed when taking the car back to the dealer to avoid overwriting or can they be overwritten without issue?
4.) Legitimacy of supporting mods like headers, intake piping, IPD, filter..........

I have an Authorized shop just down the road and even they are having difficulty gathering information.

So, you ask why APR? If they won't respond why deal with them? That answer is based on the tremendous amount of R&D I have seen they have greater knowledge of the 991.2's than any other source. Their test mules have more money in the data logging equipment and R&D time than most of the independent tuners do in their shop. There are certainly some great tuners out there but the R&D that I have seen with APR is at the level I would expect for a premier tuner yet rarely encounter.

 

I think you're a regular so this may not be revelatory... have you tried tagging their engineer Tyler anywhere? @Tyler@APR He's generally on these forums and has always been a huge help answering technical questions.

If you don't have any success getting him into this thread, maybe try asking your specific questions directly in the APR 3.0T thread. https://rennlist.com/forums/991/1172...u-upgrade.html

I would think there's no better person to ask since he's the one developing the tunes and working on understanding the platform, aftermarket turbos, etc, and on his own car to-boot.

 

I'll just add what I know:
At this point only APR dealers can switch the tune. APR are working on an at-home solution, and many of us are waiting for that to be available before committing.
As I understand it, the tune will work without any upgraded hardware, but intercoolers add a performance advantage at least with the GTS or bigger turbos. Tyler's 9-second 1/4 mile run was done with TiAL turbos and TiAl intercoolers, but otherwise stock hardware on a "T" if you can still call it that.
X51/GTS tune is available. I don't think the aftermarket, upgraded turbo tune (TiAL/Pure) is available just yet. I know they have worked with one other customer on Pure turbos (maybe @cosmo1?) so they may be able to help you on a one-off basis if you're super eager...? Since the aftermarket upgraded turbos tune isn't availalbe yet, they don't appear to have a dyno chart on their website showing the differences between X51/GTS and the upgrade tunes, but I do think they posted data somewhere here.
As above, only the APR dealer can switch tunes or back to stock at this time. If a Porsche dealer overwrites the tune, you just have to pay your APR installer to reinstall. No other issues I don't think.
The tune supposedly works without any supporting mods. Tyler has mentioned some components, including the IPD, filter, and exhaust on this platform are not restrictions (i.e. upgraded components are not likely to add much benefit). The TiAL air inlets produce a measurable benefit in compressor efficiency. And I think the turbo inlets do as well (TBD). Tyler mentioned he was going to look into the stock vs. aftermarket headers soon. Others have said headers are beneficial (they are better for sound if nothing else), but I don't think there's data-driven consensus on this yet aside from CFD analysis.

 

Thank you very much for the help! I was not sure who was doing the development. The folks I did talk with at APR were cordial but just did not have the back ground to elaborate on the details I need to get this car where I need it without throw parts on and hoping.

 

Yeah, Tyler is the man. He's extremely busy, but very thorough in his responses when he does take a break away from the dyno. His personal car is the red Carrera T in the all the APR info and he made 700whp with the Tial M660s, intercoolers, plenum, inlets, and headers. Cosmo1's car is the other 700whp car that Tyler tuned with Pure turbos, Vektor hearders, AMS intercoolers, and maybe a couple other things.

Relevant posts
https://rennlist.com/forums/991/1172...l#post16788590
https://rennlist.com/forums/991/1198...l#post16786534

As for header testing, the only detailed test I've seen was done on the Vektor headers a couple years ago on a completely stock Carrera S. So it has dyno testing including datalogs showing a reduction in transient response time.
https://motoiq.com/testing-vektor-pe...e-911-carrera/

To get to a higher level, call it OEM style, test. High frequency pressure transducers would need to installed in a runner right at the exhaust port of the head of the engine and one at the turbine inlet of the turbocharger. Something with a few khz sampling frequency in order to capture pressure vs. crank angle in order to measure the amplitude of the pressure peak at the exhaust port vs. the amplitude at the turbine inlet. The better header will have the lowest loss of pressure peak meaning more energy is getting to the turbine wheel. In the absence of the high frequency pressure transducers, I guess regular ones might capture enough of the delta pressure from exhaust port to turbine inlet, but it's certainly not as clear of a picture.

 

APR is getting close to officially releasing their tune for the 991.2 and PDK .. I just got mine back last week, the white 991.2 with the pure hybrids and it is INCREDLE now... Not able to switch maps yet but they are working on it...
Just to add i was told the headers and the catless dp's really didn't add anything due to the stock cats flowing just fine even with bigger turbos...

 

Yes, a tune can be switched, but as of right now there is only the ability to have one tune on the car at a time. APR is working on a file switching at home option but there are no further details. For example, I was running the 91 octane APR programming and wanted to switch to the E85 file. Called up my APR dealer who came to my house and switched the file for me. When it came time to go back to stock, they them removed the APR programming and I gave the car back to the dealer.

The plugs do not need to be changed.

There is no need to upgrade the low pressure fuel pump for any of the programs that they have released to the public.

I would never expect to see a "flex fuel" file in which the ECU automatically switches the programming based on the fuel that a content analyzer sees. The concept works great on a car at OEM power levels, but when you are turning up the **** to 8 or 9, there needs to be extreme caution as to ensure that there is proper fuel in the car. You can get away with it on an OEM car because on e85, they actually do not make any more power than stock.

Yes/No, APR has shown us the data on programming for TIAL Turbos, they have not released the tuning to the general public yet. If this is something you want today, have you APR dealer talk to them and see if you can be part of the beta testing program.

As of today, your APR dealer will need to switch the programming for you. I ran the APR 91 octane file, and the APR E85 file on my car with zero issues at all. When I returned the car back to stock and turned my lease back in, the car was given a clean bill of health and nothing was said. It was CPO'd and sold to a dealer to add to their inventory.

Stuff on the intake side of the turbo have show to make many positive gains (intake pipes, inlets). On the outlet side (intercooler) there is a performance advantage over OEM, however the air current that flows over the intercoolers is less than optimal, which still leaves then susceptible to heat soak. One member here did a test where he added a small "gurney flap" to the back side of the air inlet portion near the spoiler and saw a positive improvement on the road course through data logs. Prior to the small modification, his AMS intercoolers were testing out less favorable than OEM (as in once the AMS intercoolers heat soaked, they would not recover). Intake plenums have not shown any significant improvement at the levels up to GTS turbos, but they will be tested again now that there are parts available that free up the intake side of the turbochargers. The air filter is a sensible mod, just on the fact that Porsche does not use paper filters on GT cars and they supply a BMC from the factory. Stuff on the exhaust side (catalytic converters, test pipes) have not shown to make enough of a difference to support a issue with the EPA here in Murica. Headers may make a difference at the stock power level, however nobody has been able to prove that they make a difference on a programmed car. I'd imagine there are some metrics such as EGT that may be much more favorable but I have not seen that data yet.

Another good Rennlist member to ping is @3DMetal he is the designer and manufacturer of the TIAL suite of parts. He has full data-logging on his development car and has run both COBB protune and APR beta calibration.

 

Wow, fantastic information coming out of this thread!!!

Thank you all for chiming in. I often feel like the guinea pig testing products and it is so hard sifting through the forums for legitimate information, I never know who to believe.

 

And if you read some of the Cobb tune threads you will get other opinions. I have it and cannot complain as it does everything I want it to wherever I want since it has an AP.