Dragy Results for Cobb Tuned 991.2 Targa
#31
Rennlist Member
I am not sure what NPC means or what wipers have to do with tuning. I am just saying this is why I wont tune again. I had a Cadillac ATS-V with catless exhaust, air intake, fuel cam and tune putting down 530whp. Loved that car and the extra power was great. Had to make logs all the time, send files to tuner and eventually learn how to tweak tunes myself. There was always some issue that needed resolved or some part that needed to be added like the fuel cam which was not planned or upgrading cooling. Just too much to deal with and wouldnt deal with it again. Spent countless hours stressing over it and spending money on it. Maybe my experience was in minority, but not worth messing with a great car to me again. My Targa GTS will be seeing track days this year, but will not be seeing a tuner. As for investment car, I did not buy it as an investment but as a car that had everything I needed and wanted and didnt need to be messed with. If others want to tune their car, I dont care. I just wish before I got into it a couple years ago, someone would have warned me about possible unintended consequences that I dealt with. I am now in the camp of if I want more power I will upgrade to a faster car.
#32
Three Wheelin'
Thread Starter
Ok guys, so here is the update and some much better Dragy results.
The traction control on or off has no bearing on the problems I am seeing on shifting.
I did a few runs manually which were better, but the problem is the PDK tweak that Cobb did.
How do I know? I flashed the car back to the stage 2 tune, and off of my Pro Tune, the shifts were much better (still not perfect) and I ran a 3.0 flat 0-60 with stock stage 2 map.
Please comment back on my results as I like to know what others opinions are of my numbers. I am not a racer or drag strip guy, so I don't know how good or bad my numbers really are.
Here you go, I added a few more tests and YES I did pick the best results from each test.
The traction control on or off has no bearing on the problems I am seeing on shifting.
I did a few runs manually which were better, but the problem is the PDK tweak that Cobb did.
How do I know? I flashed the car back to the stage 2 tune, and off of my Pro Tune, the shifts were much better (still not perfect) and I ran a 3.0 flat 0-60 with stock stage 2 map.
Please comment back on my results as I like to know what others opinions are of my numbers. I am not a racer or drag strip guy, so I don't know how good or bad my numbers really are.
Here you go, I added a few more tests and YES I did pick the best results from each test.
#33
Rennlist Member
#35
Rennlist Member
Ok guys, so here is the update and some much better Dragy results.
The traction control on or off has no bearing on the problems I am seeing on shifting.
I did a few runs manually which were better, but the problem is the PDK tweak that Cobb did.
How do I know? I flashed the car back to the stage 2 tune, and off of my Pro Tune, the shifts were much better (still not perfect) and I ran a 3.0 flat 0-60 with stock stage 2 map.
Please comment back on my results as I like to know what others opinions are of my numbers. I am not a racer or drag strip guy, so I don't know how good or bad my numbers really are.
Here you go, I added a few more tests and YES I did pick the best results from each test.
The traction control on or off has no bearing on the problems I am seeing on shifting.
I did a few runs manually which were better, but the problem is the PDK tweak that Cobb did.
How do I know? I flashed the car back to the stage 2 tune, and off of my Pro Tune, the shifts were much better (still not perfect) and I ran a 3.0 flat 0-60 with stock stage 2 map.
Please comment back on my results as I like to know what others opinions are of my numbers. I am not a racer or drag strip guy, so I don't know how good or bad my numbers really are.
Here you go, I added a few more tests and YES I did pick the best results from each test.
#36
Rennlist Member
Also I’d love to see your 1/2 mile with out letting out to early. Looks like it may be a record. Your 1/8 trap is higher than I’ve seen. The 60-130 had a weird shift as you indicated and should easily knock down that time down a tenth or maybe two once it’s sorted out. Try to focus on 60-130 as it’s best indicator of power and takes Driver out of equation the most of these metrics. Additionally I’m surprised to see a best 60’ of 1.73. I figured with the PDK you could put down a 1.6 or better.
#37
Rennlist Member
Another variable that is good to know is the ambient temperature. A quick look at the weather shows it as being in the thirties there perhaps?
A rough rule-of-thumb I recall is that each 10 degree drop in temperature improves horsepower by about 1% due to improved air density. So if it is 40 degrees when you are doing your runs, you should be getting about 3% more horsepower than you would at 70 degrees, or about 13 horsepower or so for our cars.
A calculator you might find handy to assess such effects can be found here: https://wahiduddin.net/calc/calc_hp_dp.htm
It takes into account altitude, humidity, and barometric pressure as well.
A rough rule-of-thumb I recall is that each 10 degree drop in temperature improves horsepower by about 1% due to improved air density. So if it is 40 degrees when you are doing your runs, you should be getting about 3% more horsepower than you would at 70 degrees, or about 13 horsepower or so for our cars.
A calculator you might find handy to assess such effects can be found here: https://wahiduddin.net/calc/calc_hp_dp.htm
It takes into account altitude, humidity, and barometric pressure as well.
Last edited by StormRune; 01-12-2019 at 07:42 PM.
#38
Three Wheelin'
Thread Starter
I have video showing the unusual shifting. I of course dont want to upload it publicly or online for obvious reasons.
I will send Cobb video, data logs, dragy results, etc to see if they can hammer out the PDK problem. If this thing could shift properly it would be a rocket..
I will send Cobb video, data logs, dragy results, etc to see if they can hammer out the PDK problem. If this thing could shift properly it would be a rocket..
#39
1/4 mile
Another 128MPH - 520HP at the crank or around 450HP at the wheels.
Are you running in sports plus and using launch control?
With turbo charged cars a very crude rule of thumb is a good tune will give you the original crank HP delivered to the wheels.
In your case with the GTS it had 450HP at the crank and now, based on your 1/4 mile mph you have about 450HP at the wheels or 520HP at the crank.
The speed achieved at the at the end of the 1/4 is very diagnostic in terms of HP.
A gain of +70HP is a nice outcome - most of this will be from the tune.
Another 128MPH - 520HP at the crank or around 450HP at the wheels.
Are you running in sports plus and using launch control?
With turbo charged cars a very crude rule of thumb is a good tune will give you the original crank HP delivered to the wheels.
In your case with the GTS it had 450HP at the crank and now, based on your 1/4 mile mph you have about 450HP at the wheels or 520HP at the crank.
The speed achieved at the at the end of the 1/4 is very diagnostic in terms of HP.
A gain of +70HP is a nice outcome - most of this will be from the tune.
#41
#43
#44
I think the 60-130 time could see some improvement...
1/4 miles looks sweet, as does the 0-60 times.
Any logs with these runs? Specifically the 60-130...I feel like you're losing some umfff past 90mph (I think that should be nearing the top of 3rd gear)...
Your 1/2 miles could easily be sub 16 at full tilt.
Appreciate you starting this thread; haven't had this much fun on Rennlist in a while!
1/4 miles looks sweet, as does the 0-60 times.
Any logs with these runs? Specifically the 60-130...I feel like you're losing some umfff past 90mph (I think that should be nearing the top of 3rd gear)...
Your 1/2 miles could easily be sub 16 at full tilt.
Appreciate you starting this thread; haven't had this much fun on Rennlist in a while!
#45
Three Wheelin'
Thread Starter
Even when I shift manually and not using race launch, the car will automatically do some funky rev limiting. In 3rd gear it will just shift at 6000 and never let me get to 7500. Thats a huge issue with the PDK Tune.
I cannot explain what is happening but, Cobb will be getting everything Monday morning and I'm sure they will figure it out
I am certain that the issue with 1st gear and 3rd gear alone would be enough to seriously limit my run times. Let me get it dialed in and I will show everyone my best times and runs, but I need to be able to shift first
I cannot explain what is happening but, Cobb will be getting everything Monday morning and I'm sure they will figure it out
I am certain that the issue with 1st gear and 3rd gear alone would be enough to seriously limit my run times. Let me get it dialed in and I will show everyone my best times and runs, but I need to be able to shift first