991.2 Cobb Accessport, post your results
#511
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Agreed. 🤣
However, I don’t want to start a flame war with APR, but there is a very good reason why i have only run 50% E85 in the tank and no more yet.
E85 needs at least 30% more fuel pumped in.
If you run 100% E85 without increasing injector size or Port injection, you will run as lean as ****. Whilst you may get away with that for short 1/4 mile busts. Eventually you will go BANG!!! So this was a 1/4 tune. Run 100% E85 without the ability to add more fuel and you will blow your motor.
I’m a track rat. I’m not interested in an1/4 mile tune. My car has a bullet proof tune. I run laps all day, and i visit the track frequently when not locked down lol.
I wouldn’t advise anyone to run 100% E85 without extra duel system. It will end in tears.
Just my opinion. As you can see from my mods, I am a crazy ****. But even i know not to go 100% E85 until I have port injection.
Too many M3/M4’s went POP!!
However, I don’t want to start a flame war with APR, but there is a very good reason why i have only run 50% E85 in the tank and no more yet.
E85 needs at least 30% more fuel pumped in.
If you run 100% E85 without increasing injector size or Port injection, you will run as lean as ****. Whilst you may get away with that for short 1/4 mile busts. Eventually you will go BANG!!! So this was a 1/4 tune. Run 100% E85 without the ability to add more fuel and you will blow your motor.
I’m a track rat. I’m not interested in an1/4 mile tune. My car has a bullet proof tune. I run laps all day, and i visit the track frequently when not locked down lol.
I wouldn’t advise anyone to run 100% E85 without extra duel system. It will end in tears.
Just my opinion. As you can see from my mods, I am a crazy ****. But even i know not to go 100% E85 until I have port injection.
Too many M3/M4’s went POP!!
Whether you run the car on the street, track or quarter mile the fueling requirements are not going to change at WOT. Maybe if you are running the car on low fuel and you happen to place it in a situation where gravity may cause the motor to lean out? In that scenario it is most certainly not that tune or the fuel that would contribute.
Last edited by Cheshi143; 06-19-2020 at 10:11 PM.
#512
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C4GTS- 3285
C4GTS Targa 3485
Carrera T 3142
Now you ask where the 700lbs comes from on MY Targa..
345lbs is just the difference in curb weight from the Targa and Carrera T
65lbs is difference from me and 150lb rider
25lbs full tank of gas
50lbs front axel lift
50lbs subwoofer
And I ran a 10.88 on the street with 38lbs of tire pressure (way high) and a mis shift from 3-4th gear
Thats 500lbs difference from my car to a Carrera T. But, lets leave my car out of this equation.
The Carrera T weight vs GTS weight is 140lbs. I disagree that this is bolt on engine parts as bigger turbos weight ounces more than smaller ones. Even if they are 2lbs heavier its negligible. You cannot compare a car that is 140lbs lighter and running E85 on a prepped race track and say that its a fair apples to apples comparison to a 140lb heavier car running pump gas on the street. The times are significantly better with the APR car and tune because it is lighter, is running race fuel and was timed on a prepped track where tire spin is minimal and speed conditions are optimal.
A 10.88 vs a 10.48 is 4 tenths a a second faster and while that is a lot in the racing world, the aforementioned advantages it had doesn't mean the tune was better. Both cars could have had identical tunes and the APR would still win on weight, fuel and track conditions alone.
C4GTS Targa 3485
Carrera T 3142
Now you ask where the 700lbs comes from on MY Targa..
345lbs is just the difference in curb weight from the Targa and Carrera T
65lbs is difference from me and 150lb rider
25lbs full tank of gas
50lbs front axel lift
50lbs subwoofer
And I ran a 10.88 on the street with 38lbs of tire pressure (way high) and a mis shift from 3-4th gear
Thats 500lbs difference from my car to a Carrera T. But, lets leave my car out of this equation.
The Carrera T weight vs GTS weight is 140lbs. I disagree that this is bolt on engine parts as bigger turbos weight ounces more than smaller ones. Even if they are 2lbs heavier its negligible. You cannot compare a car that is 140lbs lighter and running E85 on a prepped race track and say that its a fair apples to apples comparison to a 140lb heavier car running pump gas on the street. The times are significantly better with the APR car and tune because it is lighter, is running race fuel and was timed on a prepped track where tire spin is minimal and speed conditions are optimal.
A 10.88 vs a 10.48 is 4 tenths a a second faster and while that is a lot in the racing world, the aforementioned advantages it had doesn't mean the tune was better. Both cars could have had identical tunes and the APR would still win on weight, fuel and track conditions alone.
What is really crazy is that even though 10.88 seems pretty close to a 10.41, at 125MPH/130MPH trap speed the cars are traveling around 183/190 feet per second, given the approximate half second difference that is around 87/89 feet.
The 911 is approximately 14 feet long, there would be at least 4/5 full car lengths between your front bumper and the APR 911 rear bumper if you were on the same track at the same time.
Last edited by Cheshi143; 06-19-2020 at 10:47 PM.
#513
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That is not quite correct. There is plenty of fueling available with the 3.0T. I ran full e85 since the tune was released and had absolutely zero issues, my data logging was spot on and the power delivery was amazing.
Whether you run the car on the street, track or quarter mile the fueling requirements are not going to change at WOT. Maybe if you are running the car on low fuel and you happen to place it in a situation where gravity may cause the motor to lean out? In that scenario it is most certainly not that tune or the fuel that would contribute.
Whether you run the car on the street, track or quarter mile the fueling requirements are not going to change at WOT. Maybe if you are running the car on low fuel and you happen to place it in a situation where gravity may cause the motor to lean out? In that scenario it is most certainly not that tune or the fuel that would contribute.
i would want to see those logs. See air fuel ratios.
Injector duty cycles.
pump gas is Stoichiometric is 14.7
E85 is 9.6. That is a dump truck load richer.
If you want to blow an engine, just fill up a stock car with E85. You will blow the motor, because you lean out.
You are tuned, and TIP in is helping save your motor.
I believe your fuel trims are maxed out on E85. That will lead to tears.
When tuning you want to get the car back to not tipping in. Thats built in safety. At max tip in, you are flying high without a net.
Everything is fine, until its not. Its like tightening a bolt. A bit more, a bit more, STRIP. Too late, can’t loosen it off once stripped. Its cooked.
In saying all of that, the Porsche ECU does have incredible tip in. You can add 9 Litres of E85 to a Stage 1 OTS tune and tip in will compensate, and give you a huge smile.
Last edited by 4 Point 0; 06-20-2020 at 06:45 PM.
#515
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Most cars are only very low, like 10%. But i have seen our cars tip in 45%.
Whilst that is impressive from Porsches side, you don’t want your car relying on tip in.
Its a meant to be a back up safety measure, not a constant state.
Ultimately, to build in longevity and safety, you want the tip in doing nothing.
Its there as a safety net. To run 100% E85, without either larger injectors or port injection, tip in would be maxed out. And if it can’t add enough, you lean out and POP it.
Imagine if your injectors are firing at 95% and then tip in needs to add 20%? It can’t, the injectors are maxed out and BOOM.
E30, the injectors have head room for tip in to operate and not max out the injectors.
#516
Drifting
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I understand tip in. E30=30% ethanol. Considering you said you can add 9 liters of e85 to a OTS tune, wouldn’t that be about the same ethanol content?
edit-just did the math...with a 16 gallon tank and using 9 liters of e85 and the rest 93 octane that’s about 21% ethanol.
edit-just did the math...with a 16 gallon tank and using 9 liters of e85 and the rest 93 octane that’s about 21% ethanol.
#517
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To run E30 you should be tuned for it. With a protune, Tip in should be able to cope.
But anything more than 9 litres, you need to be tunes for. Anything more than 50% E85, yoy ahould have extra fueling. Getting away with it os one thing . Longevity and never woreying about blowing up is another.
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polobai (06-21-2020)
#519
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Don’t confuse what i said. 9 litres in a 64 litre tank is not E30.
To run E30 you should be tuned for it. With a protune, Tip in should be able to cope.
But anything more than 9 litres, you need to be tunes for. Anything more than 50% E85, yoy ahould have extra fueling. Getting away with it os one thing . Longevity and never woreying about blowing up is another.
To run E30 you should be tuned for it. With a protune, Tip in should be able to cope.
But anything more than 9 litres, you need to be tunes for. Anything more than 50% E85, yoy ahould have extra fueling. Getting away with it os one thing . Longevity and never woreying about blowing up is another.
Just buy the OTS APR E85 tune. Have any Protuned cars know of run any real dataloging equipment? Not the AP dataloger as it is useless, the factory sensors are not to be trusted on COBB because all of the values are manipulated.
I good friend of mine added proper dataloging via external sensors and AEM AQ-1 an immediately removed his protune once he saw the data. His car now (991.2 C2) runs 60-130 in under 7 seconds on CA 91 octane fuel with APR programming.
I've ridden in this car, it is as close to perfection as you can get. I have ridden in Cobb pro tuned cars, they are not.
#520
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LOL@PROTUNE...
Just buy the OTS APR E85 tune. Have any Protuned cars know of run any real dataloging equipment? Not the AP dataloger as it is useless, the factory sensors are not to be trusted on COBB because all of the values are manipulated.
I good friend of mine added proper dataloging via external sensors and AEM AQ-1 an immediately removed his protune once he saw the data. His car now (991.2 C2) runs 60-130 in under 7 seconds on CA 91 octane fuel with APR programming.
I've ridden in this car, it is as close to perfection as you can get. I have ridden in Cobb pro tuned cars, they are not.
Just buy the OTS APR E85 tune. Have any Protuned cars know of run any real dataloging equipment? Not the AP dataloger as it is useless, the factory sensors are not to be trusted on COBB because all of the values are manipulated.
I good friend of mine added proper dataloging via external sensors and AEM AQ-1 an immediately removed his protune once he saw the data. His car now (991.2 C2) runs 60-130 in under 7 seconds on CA 91 octane fuel with APR programming.
I've ridden in this car, it is as close to perfection as you can get. I have ridden in Cobb pro tuned cars, they are not.
i understand budget guys want to pay 2 hours max on dyno for a tune. Mine has many hours on the dyno.
#521
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I have run the AP on my own car and I have purchased a protune from the most respected tuner. I also took that crap off my car and switched to APR the moment that the programming was available.
You spend as much time as you want on the dyno or on the street with the accessport/protuning user interface and you are not going to be able to overcome the limitations of the hardware/software.
Mitch is working to overcome this now and eventually he may or may not be able to.
Right now, what you are running on your car is unsafe. I guarantee it. There are many inherent tuning protection interventions that the factory DME has in place which have been either eliminated or overridden to allow the Cobb to perform on the 991.2. These limitations are just coming to light as customers have been asking for more and more and the Cobb Accessport is unable to deliver.
Just for the fact that your tuner is willing to allow you to add 15% to 20% of ethanol to pump gas and allow the fuel enrichment of the DME to adapt for it should be enough warning for you to run for the hills.
Just remember when your car fails, I warned you.
#522
Three Wheelin'
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I am certainly enjoying this thread. I have a pro tune but, I am not opposed to jumping ship if APR ever comes out with real data to show they are the tune to beat.
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
Until they do, I am staying put and hoping Mitch can and will finish what he started. The fact he is advertising 992 tuning now is a little disheartening, when he hasn't even fully cracked the 991's...
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
Until they do, I am staying put and hoping Mitch can and will finish what he started. The fact he is advertising 992 tuning now is a little disheartening, when he hasn't even fully cracked the 991's...
#523
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I am certainly enjoying this thread. I have a pro tune but, I am not opposed to jumping ship if APR ever comes out with real data to show they are the tune to beat.
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
They claim you don't need injectors or a fuel pump to run E85. I find that really hard to believe.
#524
Advanced
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I’ve been following this thread since the beginning and scratching my head at times. I also have a pro tune on my 991.2 T. My pro tuner and I talked about keeping boost at a safe level on the car. We also know that generally an increase in boost = increase in HP and TQ. My gains aren’t equal to what APR, but everything I’ve researched tells me a pro tune on my car is the way to go for safety and reliability.
I am certainly enjoying this thread. I have a pro tune but, I am not opposed to jumping ship if APR ever comes out with real data to show they are the tune to beat.
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
Until they do, I am staying put and hoping Mitch can and will finish what he started. The fact he is advertising 992 tuning now is a little disheartening, when he hasn't even fully cracked the 991's...
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
Until they do, I am staying put and hoping Mitch can and will finish what he started. The fact he is advertising 992 tuning now is a little disheartening, when he hasn't even fully cracked the 991's...
#525
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I am certainly enjoying this thread. I have a pro tune but, I am not opposed to jumping ship if APR ever comes out with real data to show they are the tune to beat.
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
Until they do, I am staying put and hoping Mitch can and will finish what he started. The fact he is advertising 992 tuning now is a little disheartening, when he hasn't even fully cracked the 991's...
Showing Drag slips on stripped down cars running E85 or Ethanol doesnt mean a thing to me. I want to know what they can do on pump gas and I want dyno numbers to prove it.
Until they do, I am staying put and hoping Mitch can and will finish what he started. The fact he is advertising 992 tuning now is a little disheartening, when he hasn't even fully cracked the 991's...