flickroll

Do whatever you feel comfortable with. The headers, for me, had biggest butt dyno gain except for the ecu tune.. I have never thrown a CEL. Before the ecu custom tune I was making the same HP as a Turbo which was proven by the baseline dyno run. Don’t want to get into a pi**ing contest with anyone, just telling my experience which has been awesome. Glad I did the mods that I did and have not looked back.

AdamSanta85

I got my first 911 only a month or so ago, and I am already torn on my next... GT3 vs GTS. Modded GTS's are monsters.

Psorcery

Congrats! What did you end up buying? I've got a pretty fast GTS and I still yearn for a GT3.. Especially in manual... Or as the Mexicans say "Manuel".

VektorPerformance

Headers will definitely be the no 2 power adder after a tune. HF cats do allow going to Cobb stage II tune which is also a nice bump. HF cats without a tune are most likely to throw a CEL. Although, that seems to be dependent on which HF cat setup you go with.

The stock ECU (tune) can adjust for changes in volumetric efficiency and cope with additional power quite well. If feedback shows excessive heat soak, boost, AFR, knock, etc., it does a great job making the necessary adjustments to keep things safe (reducing timing, throttle, boost...). Heck it will even sense an event in a single cylinder and make an adjustment; gradually bringing conditions back if the condition is not seen again.

Torque limits on the other hand, once you exceed the allowable tolerance, are lines that cannot be crossed except with a tune. In short, you can make some power without a tune, but to maximize the power potential of installed components a tune is necessary. Especially as the number of bolt-ons goes beyond 'standard' OTS tune capabilities; you will hit the same load limit wall even with a Cobb OTS tune. This again is why it's paramount to have a pro-tune performed, or you are likely are leaving power on the table.

luv2sleep

I have headers, 200 cell SOUL cats, and no tune (yet). No CEL here. FYI

VektorPerformance

IIRC the Soul setup has HJS cats. HLS cats are higher end cats. I've yet to see a CEL when HJS cats are used.

You are VERY likely ECU power limited with those mods You should be able to make REALLY big gains with a tune

Soul Performance

You are correct, sir! We have a flawless no catalytic converter related CEL record. Cheers!

-Mike

SeeForce

my ecu box arrived last night! didnt have time to remove and im traveling for 4 days!!!! ugh.

991.two

Have you had a chance to get your ECU out and shipped?

cosmo1

Highly recommend Hydra Motor Works in west palm. Try 550wtq at only 3k rpm's on my Pure Turbos, smooth as stock...
Vektor Headers
BMC Filter
Soul Catless DP's
PSE
Pure Turbo's
Incredible Car now!!!

991.two

Can you tell me a little about your "Pure Turbos"? Larger than the S or GTS turbos?

cosmo1

Larger than the GTS. Contact Jesse at Pure for more info...
Here is a run I did with a Ferrari 458 from a 80 roll in Mexico..

Hydra Motor Works

Thanks @cosmo1 ! You're car is an animal haha!

"No tune (yet)" - Let's make it happen! I'd be happy to get you set up.

Bill_76

See you on Tuesday Hydra, lets see the change with your custom tune and the cat-bypass pipes in my GTS

Hydra Motor Works

Oh it's going to be a blast!