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Arter: There are so many variables that its nearly impossible for anyone to have a definitive answer. Personally, I dont know why there could be a bigger benefit BEFORE the tune using the IPD then AFTER the tune. If you can explain to me your thinking I would be interested. If anything, I would think that AFTER the tune it would/could produce better gains because a custome tune could account for the "higher flow" and the engine tuned would also benefit more from "increased flow" as boost, heat, etc. increased.
I have a proposition...
Why dont we start a Dyno fund to help John out? He is doing this for all of us and we all benefit from his work. Even $10 would lower his costs and allow us better and more accurate testing.
I am in for $50 towards a dyno run at 11:30AM using the sport Plus button so we can eliminate 2 more variables from this IPD situation and see if can do anything better than the first time.
John: Call or PM me and I will send you $50. I want another run eliminating the variables you forgot. Lets get an apples to apples test. NO FANS
I appreciate your offering but I'm gonna stick to my plan as intended. As I've said, this car heat soaks so much that chassis dyno testing isn't very scientific.
As for the discussion about dynoing the plenum with and without the Cobb, the Cobb is an off the shelf tune at the moment and is not tailored to the IPD Plenum. No one is making custom 991.2 tunes at the moment because the Pro Tuner software is not yet available for the 991.2 and 718. When it does become available I will attempt to modify the tune for the IPD but I don't see much potential because there's only so much you can do to try and accommodate for something that is basically speeding up air velocity.
I dyno'd one of the first plenums ever made in 2004. When you're on the dyno and at wide open throttle, the Plenum's value is diminished. On the race track and on the dyno you're full throttle; on the street you aren't.
Keep your dollars and I will keep on my path. I barely had enough time to dyno the Plenum last week but you kept asking me about it so therefore I did it because I told you I would.
Arter: There are so many variables that its nearly impossible for anyone to have a definitive answer. Personally, I dont know why there could be a bigger benefit BEFORE the tune using the IPD then AFTER the tune. If you can explain to me your thinking I would be interested. If anything, I would think that AFTER the tune it would/could produce better gains because a custome tune could account for the "higher flow" and the engine tuned would also benefit more from "increased flow" as boost, heat, etc. increased.
I have a proposition...
Why dont we start a Dyno fund to help John out? He is doing this for all of us and we all benefit from his work. Even $10 would lower his costs and allow us better and more accurate testing.
I am in for $50 towards a dyno run at 11:30AM using the sport Plus button so we can eliminate 2 more variables from this IPD situation and see if can do anything better than the first time.
John: Call or PM me and I will send you $50. I want another run eliminating the variables you forgot. Lets get an apples to apples test. NO FANS
In all seriousness if someone sets up a go fund me for his dyno time I will (and likely many others) be happy to donate.
Arter: There are so many variables that its nearly impossible for anyone to have a definitive answer. Personally, I dont know why there could be a bigger benefit BEFORE the tune using the IPD then AFTER the tune. If you can explain to me your thinking I would be interested. If anything, I would think that AFTER the tune it would/could produce better gains because a custome tune could account for the "higher flow" and the engine tuned would also benefit more from "increased flow" as boost, heat, etc. increased.
It was what I saw with several people tuning and modding cayman N/A motors. Most mods ease the ability of the car to pump air through the motor to increase power.
As you add mods, it becomes incrementily harder to make further gains even with tunes.
So on the N/A caymans (981S) if you added the IPD first, you could show a 10-15 hp gain with a tune. What the vendor promised.
If you did headers and sport cats with a tune ( 20-35 hp gain) and then added the IPD later you got 0-7 hp depending upon if you got a custom tune or not.
So in the absence of any tune, the addition of the IPD could improve air flow on a stock, unmodified 991.2 to show a benefit.
With the large increase in boost increasing airflow, what the IPD could do for airflow is mostly swamped out.
My bottom line is that with the tune present, the IPD is not worth the effort or cost ( for me
4 point 0: Well, I think the opposite. I think you know it doesnt work. I think you have buyers remorse. I think you probably feel like an A hole for buying a part that reduces power, but you need to come on the forums to justify your announcement publicly that you bought and installed this POS. I'm telling YOU this as a friend.
About no one wanting to deal with me, I mean do you just make this stuff up because you are creative? You dont know me or any of the three speedshops who deal with me. I had the entire back of the car apart, including air filter to get to the ECU and the labor was zero, it was right there if I wanted to install it. The mechanic cold have put any plenum I wanted back at that point and he said dont even bother. The stock plenum was sitting on the floor in front me and we examined what it was and what it was doing. Makes no sense to change it and the dyno supports that.
"I did my own dyno's with the Fans ON: By all means please show us the results, that would certainly support your claims that it produces power rather than you beating guys on the street that you couldnt before which introduces about a dozen variables and reasons why you lost then and win now. Show the dyno charts.
"This is an air flow mod. It is never going to show real results with zero airflow. Please argue with this. PLEASE."
Ok, I will.. Both tests were done without fans. Both parts are airflow parts. Since both tests were performed under the same conditions then the IPD should show IMPROVEMENTS NOT REDUCTIONS over stock. The larger diameter, the dimpled interior, the improved design.. complete Horse ****. If it flows more air then why cant it flow more air than the stock part under the same conditions? Please argue with this, PLEASE.
The car PULLS air into the engineand there is no reason why a part that claims to be able to increase airflow, HP and Torque cannot do so over a stock "restrictive" part.
Of course fans would help with flow, but it would help with flow on BOTH plenums, not just the IPD plenum. Same with heat soak, fans would help but, heat soak would still occur on both even with fans.
If I had installed this part on my car I would not only ask for a refund, but I would ask the company for money back to cover the labor to install and remove it. Its cheap for a reason and it doesnt work.
I'm certain I speak for many when we tell you how happy you are you have one, enjoy it. We are happy we don't. XOXO
As I do not have a tune yet, just the IPD and AMS intercoolers, would you like to see a Video of me Pulling on a 991.2 GT3?
It caught upto me and then I let it go around me, as its brakes were superior. And a better driver. The footage is from his car. And you can clearly see me pull away from him down the main straight.
Now I don't think anyone believes the GTS UNTUNED is faster than a 991.2 GT3. But I have video proof. I may need assitance in how to up load it somewhere so people can see it.
But before I show the Video, please give me the excuses why I was able to pull on a 500 HP 991.2 GT3 down the main straight when I am not tuned and all I have is the IPD and the AMS intercoolers. They won't do anything until the tune either. SO I guess that cheap mod made some sort f difference. The video is on facebook. I will share with JOHN and he may be able to share it with you.
4 point 0: Now I believe you. There is no question the IPD plenum was clearly the reason you pulled on a GT3. There can be no other explanation, you dont need to upload the video. That is proof enough for me.
4 point 0: Now I believe you. There is no question the IPD plenum was clearly the reason you pulled on a GT3. There can be no other explanation, you dont need to upload the video. That is proof enough for me.
Unless the GTS is just a faster car. Which upsets everyone if you even hinted at it.
I don't see why you are all bent out of shape that it does something? It can't be much. And I agree that as it was the first mod, the first mod gets the low hanging fruit.
I have also experienced this with other cars and other unrelated mods. So that does offer a sound explaination.
So I'm curious.... what are you guys seeing for intake manifold air temps vs ambient air temps while on track?
Well, ran at Laguna Seca this weekend and recorded some datalogger values.
Was going to compare stock tune vs Cobb run, but the datalogger gods ate the stock data. ( but I saved the Cobb values).
2018 Carrera GTS with Cobb ron 91 tune, Laguna Seca 80F ( yeah quite cold, not like the 110F we have on the southern cal tracks right now so best case).
Running one lap ( after about 15 minutes running on track at 80F, the Intake temp bounced between 134 and 165F. It seemed to
cycle betwwen these values. This is with the stock intercooler.
Boost, calculated torque, and throttle positions are shown for the pull down the main straight ( again after 15 minutes on track.
This is coming around turn 11 ( a very slow corner) and then running up the main straight at Lagune Seca.... a 12 second window of time mostly on full boost.
The brown line is throttle position, starts with zero throttle as I go ito the corner, and then increases as I corner, and then fully floored as I get off the astro turf outside the corner.
The throttle blade is what the ECU is actually doing to control output. 81 degrees is full open,
As the PDK shifts gears ( rpm red line), the throttle bounces and corrects to keep the torque ( light blue line) from getting too high
(after the first shift, torque increased to 540 ft-lbs and the throttle dropped it to 480 before being happy).
Boost was 24 psi during this run up the straight ( boost pre minus 14.7 which produced a small negative number while idling).
But the car guage showed 19 psi during this time ( corrected or "fooled"?).
So the Cobb tune seemed to work, but it didnt make me a better driver
Only second time at Laguna Seca, and still very cautious in its turns which is what makes the times.
I would love to see those raw logs. Would you mind emailing them to me? Keep in mind that Laguna, while uphill, is a low grip surface and favors handling over power. We ran both race cars there in 2013 and the Cayman was down almost 65rwhp but was faster on slicks than the 911 that won the GS race. The Cobb might make more torque and horsepower but a hooked up car at Laguna will reign supreme. There are some uphill corners that definitely benefit from the torque but she's gotta turn down to the apex at that place.
I always log all boost parameters on the Cobb because it's nice to see any changes in boost and confirm whether or not the ECU is shutting things down.
I take that back about the IATs. I misread that chart.
While you are here, here is the ignition timing I got during a lap.
I see reduction of timing to prevent knock during hard acceleration ( 91 octane), but I am not an expert on if this amount is normal ( do I need 93?).
I see cyl 1 is running a little "hotter" than the other cylinders.
As I do not have a tune yet, just the IPD and AMS intercoolers, would you like to see a Video of me Pulling on a 991.2 GT3?
It caught upto me and then I let it go around me, as its brakes were superior. And a better driver. The footage is from his car. And you can clearly see me pull away from him down the main straight.Now I don't think anyone believes the GTS UNTUNED is faster than a 991.2 GT3. But I have video proof. I may need assitance in how to up load it somewhere so people can see it.
But before I show the Video, please give me the excuses why I was able to pull on a 500 HP 991.2 GT3 down the main straight when I am not tuned and all I have is the IPD and the AMS intercoolers. They won't do anything until the tune either. SO I guess that cheap mod made some sort f difference. The video is on facebook. I will share with JOHN and he may be able to share it with you.
Again (my posts), Hp is not directly related to acceleration at lower speeds. Torque is what gets a Porsche accelerating at lower speeds, and the 3.0 twin turbos own big torque. At high speeds and towards the end of long straights, GT3 Hp rules. Let's look at torque for the 475, 500 and 520 Hp GT3's versus the 450 Hp GTS and X51 C2S. The 3.8 GT3 peak torque is 325 ft-lbs and the 4.0 GT3 and GT3 RS peak torques are 339 and 346 ft - lbs respectively. And they are relatively peaky, vis a vis the much higher and much broader torque curves of the X51 S & GTS.
So, even a lowly C2S can keep pace with any modern and lighter GT3, 0-60. And both an X51 C2S or GTS with flat and huge 405 ft-lb torque curve can embarrass any GT3, from 0 to at least 60. But at triple digit speeds the GT3's will quickly walk away from the X51 S/GTS, because Hp rules at triple digit speeds. This is just simple physics in our universe... For everyday street, expressway and highway driving in the USA & Canada, the 991.2 3.0 TT X51 S & GTS give up nothing to the GT3 models. But on high speed tracks, autobahns and canyon runs, the higher GT3 Hp will rule!
But on high speed tracks, autobahns and canyon runs, the higher GT3 Hp will rule!
COBB tune will be on shortly. That will add 100HP to the GTS. So instead of 50Hp less than the GT3, it will have 50HP more. Let's see who rules what then. : )
COBB tune will be on shortly. That will add 100HP to the GTS. So instead of 50Hp less than the GT3, it will have 50HP more. Let's see who rules what then. : )
With this much HP on these cars, it's the driver who rules