MY18 C2 Dyno Baseline
#16
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Cat Bypass? OK, assuming you don't live in an emissions test area.
Air filter? No real performance gain, but maybe a bit better intake sound? cheap enough, why not.
Plenum? Not so much.
IMHO throwing hardware upgrades at an engine that is intentionally, artificially, and heavily torque managed by software makes little sense when you can unleash a ~30% torque boost with just an ECU tune.
Certainly one isn't swapping the plenum but then worried that a tune might raise eyebrows if there was a warranty claim.
Air filter? No real performance gain, but maybe a bit better intake sound? cheap enough, why not.
Plenum? Not so much.
IMHO throwing hardware upgrades at an engine that is intentionally, artificially, and heavily torque managed by software makes little sense when you can unleash a ~30% torque boost with just an ECU tune.
Certainly one isn't swapping the plenum but then worried that a tune might raise eyebrows if there was a warranty claim.
Last edited by pfbz; 01-30-2019 at 02:52 PM.
#17
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Cat Bypass? OK, assuming you don't live in an emissions test area. Air filter? OK, why not. Plenum? Not so much.
IMHO throwing hardware upgrades at an engine that is intentionally, artificially, and heavily torque managed by software makes little sense when you can unleash a ~30% torque boost with just an ECU tune.
Certainly one isn't swapping the plenum but then worried that a tune might raise eyebrows if there was a warranty claim...
...and you are doing a cat bypass but no tune? How will you be managing the rear 02 sensors?
IMHO throwing hardware upgrades at an engine that is intentionally, artificially, and heavily torque managed by software makes little sense when you can unleash a ~30% torque boost with just an ECU tune.
Certainly one isn't swapping the plenum but then worried that a tune might raise eyebrows if there was a warranty claim...
...and you are doing a cat bypass but no tune? How will you be managing the rear 02 sensors?
#18
Drifting
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
You should pick up power with the cat bypass-with the filter I am not quite sold on as of yet. I usually run re-oilable filters on all my vehicles but @$300 for the bmc filter that supposedly does not generate more power than the $40 oem filter that lasts 20-40k miles, I don’t think it’s worth it.
#19
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
The stock air filter is MASSIVE given the airflow requirements of a 370-450hp engine. I'd guesstimate it's about 50% larger per HP of other cars. Go look at the air filter sizes for engines of similar of HP and see how big the 991.2 air filter is. That said, there are gains to be made as shown from the AMS air filter presssure drop test info below. The air filter is a restrictor and the pressure drop goes up exponentially with air velocity which increases with hp. So with bigger turbos and other mods increasing power 50%-100% over stock, the performance difference between the BMC/AMS air filters and stock will increase. That said, I personally wouldn't change out the air filter proactively. If it's time to change it or the bumper is already off for something else, then sure.
![](https://www.amsperformance.com/wp-content/uploads/2018/03/Alpha-Performance-991.2-Carrera-pressure-testing-1024x495.jpg)
#21
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Looking forward to your results.
Can you point me towards a link/video for the rear bumper removal on your C2? I know it's simple, just do not want to miss anything. I have seen other models DIY with slightly different variations.THX.
Can you point me towards a link/video for the rear bumper removal on your C2? I know it's simple, just do not want to miss anything. I have seen other models DIY with slightly different variations.THX.
#22
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
me too! I havent been able to find a bumper removal vid for a c2 specifically. im planning to follow the GTS removal posted elsewhere. If i find it to be very different, I may make one or at least outline the differences. stay tuned...
#23
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
The moment you said dynojet we can be sure it is over reading.
porsche don’t under estimate power, they measure it using a defined standard (DIN or SAE) and the engines will make the figures Porsche quote all day long.
dont get hung up on the numbers though, you can measure the improvement as a percentage and more importantly by the smile on your face - that is the most important measure![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
porsche don’t under estimate power, they measure it using a defined standard (DIN or SAE) and the engines will make the figures Porsche quote all day long.
dont get hung up on the numbers though, you can measure the improvement as a percentage and more importantly by the smile on your face - that is the most important measure
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
#24
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
The moment you said dynojet we can be sure it is over reading.
porsche don’t under estimate power, they measure it using a defined standard (DIN or SAE) and the engines will make the figures Porsche quote all day long.
dont get hung up on the numbers though, you can measure the improvement as a percentage and more importantly by the smile on your face - that is the most important measure![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
porsche don’t under estimate power, they measure it using a defined standard (DIN or SAE) and the engines will make the figures Porsche quote all day long.
dont get hung up on the numbers though, you can measure the improvement as a percentage and more importantly by the smile on your face - that is the most important measure
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
#26
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Cat Bypass? OK, assuming you don't live in an emissions test area.
Air filter? No real performance gain, but maybe a bit better intake sound? cheap enough, why not.
Plenum? Not so much.
IMHO throwing hardware upgrades at an engine that is intentionally, artificially, and heavily torque managed by software makes little sense when you can unleash a ~30% torque boost with just an ECU tune.
Certainly one isn't swapping the plenum but then worried that a tune might raise eyebrows if there was a warranty claim.
Air filter? No real performance gain, but maybe a bit better intake sound? cheap enough, why not.
Plenum? Not so much.
IMHO throwing hardware upgrades at an engine that is intentionally, artificially, and heavily torque managed by software makes little sense when you can unleash a ~30% torque boost with just an ECU tune.
Certainly one isn't swapping the plenum but then worried that a tune might raise eyebrows if there was a warranty claim.
#27
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
One can back out of the hardware upgrades but not out of a tune as the digital tracks will remain. I would personally love a tune but I don't want to take the risk yet. I may also be naive in this respect but if you only replace a few exhaust parts it seems less likely that the dealer could blame them for a problem. Maybe I'm just kidding myself though.
#28
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I would personally LOVE to see a dyno of JUST the BMC filter. Would be great to get a definitive answer on whether or not it produces gains. Any chance you will be doing the install @ the dyno shop to allow for this?
![ducking](https://rennlist.com/forums/graemlins/icon107.gif)
#30
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Im not, BUT if the bumper removal isnt too terrible, I may be willing to install the air filter and run to the dyno to take one for the team.