GIAC 991.2 Carrera 4S Tune Review
#1
Racer
Thread Starter
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I recently pulled the trigger on a tune from one of the first companies to successfully ‘crack the code’ on the new 3.0 turbo powered 991.2 Carrera S. After doing careful research and narrowing it to a handful of tuning companies, GIAC ended up at the top of the list as far as capability, positive customer feedback and experience- with over a decade of successful tunes on applications from street to track and everything in between.
As their tunes are done via ECU flash, I had the ECU out of the car in about an hour(first time being super carful-but could repeat the process in 15 minutes). I overnighted the ECU to their headquarters in CA and had it back literally 36 hours later. They were great to deal with.
After getting the ECU back in the car I patently fired and warmed it up-no check engine light(which can happen on some tunes when you initially start the car)and took it out for a drive. As traffic was heavy on my initial test I took it easy but I could feel the extra torque right away without much push of the right foot. The more surprising part is that there is no change to how smooth the car operates in light, medium or at full loads. The next day I went out for a bit more aggressive drive and wow! the car is fast!! GIAC quotes 85hp/95tq which you can certainly feel all of at full throttle. I was surprised how much I love the additional low end torque at lower rpm's also. I am exceptionally happy with the GIAC tune! The car is just more of what it already was.
So how much faster? Proof is in the numbers. A few friends and I made our way to New England Dragway this past Friday. It was my first time on a drag strip and was a lot of fun. I did not run the car before the tune so not sure what it would have done in stock form. The car ran a consistent 11.1 with my novice hands at the helm and with the wheels spinning during launch control at the start, I feel like the car could break into the 10’s(93 pump gas) on a cleaner surface. Other racers at the track couldn’t believe how fast the car was. I put a small list together below to give some perspective(Car & Driver /Road & Track test numbers). I'm betting this set up would post a sub 720's time on the Nurburgring. I am also running high-flow 200 cell cats(and Speedtech X-pipe) which might add an additional 15-25 hp. I would say the car is very close to 991.2 “Turbo” model performance with slightly less power(525hp-ish) but a few hundred pounds weight advantage. I should also mention I have a PDK equipped car. Way to go GIAC!
2017 Ford Mustang GT350R 12.2
2017 Corvette Z06 11.4
2017 Camaro ZL1 11.5
2017 Porsche Turbo 10.8
2017 GT3 RS 11.1
2017 Porsche GTS 11.4
2017 Nissan GTR 11.1
2017 Dodge Hellcat 11.4
As their tunes are done via ECU flash, I had the ECU out of the car in about an hour(first time being super carful-but could repeat the process in 15 minutes). I overnighted the ECU to their headquarters in CA and had it back literally 36 hours later. They were great to deal with.
After getting the ECU back in the car I patently fired and warmed it up-no check engine light(which can happen on some tunes when you initially start the car)and took it out for a drive. As traffic was heavy on my initial test I took it easy but I could feel the extra torque right away without much push of the right foot. The more surprising part is that there is no change to how smooth the car operates in light, medium or at full loads. The next day I went out for a bit more aggressive drive and wow! the car is fast!! GIAC quotes 85hp/95tq which you can certainly feel all of at full throttle. I was surprised how much I love the additional low end torque at lower rpm's also. I am exceptionally happy with the GIAC tune! The car is just more of what it already was.
So how much faster? Proof is in the numbers. A few friends and I made our way to New England Dragway this past Friday. It was my first time on a drag strip and was a lot of fun. I did not run the car before the tune so not sure what it would have done in stock form. The car ran a consistent 11.1 with my novice hands at the helm and with the wheels spinning during launch control at the start, I feel like the car could break into the 10’s(93 pump gas) on a cleaner surface. Other racers at the track couldn’t believe how fast the car was. I put a small list together below to give some perspective(Car & Driver /Road & Track test numbers). I'm betting this set up would post a sub 720's time on the Nurburgring. I am also running high-flow 200 cell cats(and Speedtech X-pipe) which might add an additional 15-25 hp. I would say the car is very close to 991.2 “Turbo” model performance with slightly less power(525hp-ish) but a few hundred pounds weight advantage. I should also mention I have a PDK equipped car. Way to go GIAC!
2017 Ford Mustang GT350R 12.2
2017 Corvette Z06 11.4
2017 Camaro ZL1 11.5
2017 Porsche Turbo 10.8
2017 GT3 RS 11.1
2017 Porsche GTS 11.4
2017 Nissan GTR 11.1
2017 Dodge Hellcat 11.4
Last edited by mac10; 05-14-2017 at 01:05 AM.
#2
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That's great to hear. I've been waiting to see what the tuners could do with these new turbo engines. Takes me back to when to when BMW first released their 3.0 liter turbo and you could get huge power gains just from software.
#7
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They are on my to-do list. But leaning towards doing after warranty up... is that overly cautious? I have 3 new cars and all 3 have already been in for warranty related repairs (on the 991 it was injector related).
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#8
Rennlist Member
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Awesome!!
#10
RL Community Team
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#11
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The car ran a consistent 11.1 with my novice hands at the helm and with the wheels spinning during launch control at the start, I feel like the car could break into the 10’s(93 pump gas) on a cleaner surface. Other racers at the track couldn’t believe how fast the car was. I put a small list together below to give some perspective(Car & Driver /Road & Track test numbers). I'm betting this set up would post a sub 720's time on the Nurburgring. I am also running high-flow 200 cell cats(and Speedtech X-pipe) which might add an additional 15-25 hp. I would say the car is very close to 991.2 “Turbo” model performance with slightly less power(525hp-ish) but a few hundred pounds weight advantage. I should also mention I have a PDK equipped car. Way to go GIAC!
2017 Ford Mustang GT350R 12.2
2017 Corvette Z06 11.4
2017 Camaro ZL1 11.5
2017 Porsche Turbo 10.8
2017 GT3 RS 11.1
2017 Porsche GTS 11.4
2017 Nissan GTR 11.1
2017 Dodge Hellcat 11.4
2017 Ford Mustang GT350R 12.2
2017 Corvette Z06 11.4
2017 Camaro ZL1 11.5
2017 Porsche Turbo 10.8
2017 GT3 RS 11.1
2017 Porsche GTS 11.4
2017 Nissan GTR 11.1
2017 Dodge Hellcat 11.4
Bone stock 2017 Carrera S gets 11.4 seconds @ 123 MPH. Here are the results of instrumented test:
http://www.caranddriver.com/reviews/...ic-test-review
Carrera 4S is supposed to be 0.1-0.2s faster (11.2 second q-mile) depending on track temperature. GIAC tune seems to be making a miniscule difference at the risk of voiding warranty.
#12
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Thank you for sharing your results!
I'm sure it's a noticeable improvement from a driver's perspective, but I seriously doubt the 85hp/95lbs claim though:
1) It's not the peak hp increase for sure. 2-3 mph increase in the trap speed vs the test done here is the proof:
http://www.roadandtrack.com/car-cult...mparison-test/ (done in CA, w/ crappy 91 CA gas)
I think there was at least another test have shown >120 trap speeds with stock 991.2 C4s..
2) I've had a 997.1 Turbo with Giac tune, dyno graphs were drastically different from their claims, as well as other issues that I won't go into here.
Having said that, I'm sure there's a big difference that can be felt during daily driving, and maybe even close to the claimed gains at certain rpm ranges, where on the dragstrip, you're only using, say 5700-7000 rpm.
I think a lot of people are waiting on the Cobb, since it's a better and more advanced platform that all tuners (maybe except Champion) embrace.
I'm sure it's a noticeable improvement from a driver's perspective, but I seriously doubt the 85hp/95lbs claim though:
1) It's not the peak hp increase for sure. 2-3 mph increase in the trap speed vs the test done here is the proof:
http://www.roadandtrack.com/car-cult...mparison-test/ (done in CA, w/ crappy 91 CA gas)
I think there was at least another test have shown >120 trap speeds with stock 991.2 C4s..
2) I've had a 997.1 Turbo with Giac tune, dyno graphs were drastically different from their claims, as well as other issues that I won't go into here.
Having said that, I'm sure there's a big difference that can be felt during daily driving, and maybe even close to the claimed gains at certain rpm ranges, where on the dragstrip, you're only using, say 5700-7000 rpm.
I think a lot of people are waiting on the Cobb, since it's a better and more advanced platform that all tuners (maybe except Champion) embrace.