I recently purchased a k24/18G 996tt. I love it! Its fast and currently dynos at very pleasing numbers. I noticed something that has been bothering me since i bought it...The cats, they are still there lol. I have never owned a fun performance vehicle with cats, I am dying to remove them! It currently has a fvd Brombacher exhaust with mufflers and cats. The rear 02 sensors are coded out. Will i notice anything by removing them? IE quicker spool, more power, more exotic rasp perhaps? Considering the rear 02 are coded out should i just take the plunge and gut the cats out or should i buy cat deletes from FVD?

After reading a few post last night it seems i will not need to retune in most cases. I have read that one member here needed to add a pusher 044 fuel pump as well as take his car back to EPL and get a retune, WIll that be the case? I am really looking to make the car a bit faster and sound much more exotic/louder by doing this small mod. Thanks in advanced. --Rob

 

HI,That was mine that you read..In a short story,but I do have a threads on it..When I changed my Cargraphics 200 cell cats to Speed Techs 100 cell cats,,,,I noticed it came on boost quicker and made more power in the low midrange area that I felt with my butt dyno....But nothing more on the top...Same boost on gauge...I found out that the CG mufflers were the other restriction,small dia. inner piping....When I changed to the Milltek 100 cell system with better flowing mufflers,,it pulled harder every where and thats when my boost went up .15 bars and the fuel problem...So,in a nut shell,,,,Depends on your mufflers also...Hope this helps...Good Luck....

 

For various reasons, I like to hear the turbo's , much more audible with straight pipes, exhaust note is much better in my case, car breathes better, and makes more power based on my butt dyno.

As far as the fuel pump, I was under the impression most K24/18g cars are running a single pump with upgraded injectors, unless you are running E85, or possibly C16 with high boost. I'm running 60lb injectors, with Protomotive tune, with no issues. However I have a CA 91 octane pump tune at 1.1 bar, so I'm only in the 500-520WHP range. I have not logged injector duty cycle myself, so I can't comment on how much injector I have left for a higher octane tune.

Many guys run K24/18g's on stock injectors with 5 bar FPR. I believe that setup is good to about 475WHP or so, although I would bet the injectors are maxed out at that level. So if the motronic system needs to dump fuel to save your engine, there may not be enough injector to do so. That is why many recommend injectors, so you retain a safety margin.

Have you upgraded you intake plumbing ? I was considering that as my next upgrade, looks like 911tuning has a setup that states you can install without removing the engine. http://www.911tuning.com/996-Turbo/I...ing-p-124.html Wonder if anyone has actually installed the kit without removing the engine. You should consider intercoolers as well, if you are still running the stock units.

I'm sure all the big tuners could provide an upgrade plan/path for you, Marski at 911tuning has worked with K24/18g's alot, and should be able to help.

Good luck.

 

I had 72 injectors from the beginning with the K24/18g's running 1.25 bars with the CG exhaust, on 93 oct...Drove the car down to EPL to have it tuned the best for my set-up then.....Just the new exhaust changed my fuel requirements/boost went up from swap,,,,the stock pump could not keep up with the 72 injectors, BUT the extra pump gave me more tunability and let Tony/EPL make more power with it..Now I run 1.4 bars and make more HP+ TQ...All wheel mustang dyno,,538HP and 695TQ on 93 oct....

 

Without going to much into detail, I bought Mike TTBoost;s car. It is very well set up with all the basic bolt ons including intercoolers injectors piping aquamist meth kit etc.

 

if a car has 200 cel cats on it and they were changed to 100 cell cats would the car be much louder and then if no cats would be louder also? NO cats have any effect on drone?

 

It did not change that much on my switch with the Cargraphics mufflers,,,But,,,it did have a different sound at cold srart up which was cool/exotic sounding??...I guess it all depends on the mufflers....I know the Milltek 100 cell and 200 cell systems use the same muffler and there is hardly loudness difference...

 

generally yes to all 3 ...

 

What part of the NE are you in?

Get rid of those cats...and hell while your down there, throw the dogs in the trash too. LOL (sarcastic).

 

I'm running a SpeedTech 3" X-flow system with no cats and there is hardly any drone while cruising (2-3K RPM) It WAILS at WOT but stays subdued otherwise.

 

I am from Leominster MA 40 mins out of Boston.

 

I would never run cats on a modded turbo car. Any restriction you take out of an exhaust will give your turbos quicker spool. Gut those suckers and don't look back!

 

Gut them ...huh. I Shouldn't worry about buying straight pipes right?

 

On my PSI exhaust I cant remove the cats and put test pipes in like some others out there. If you can on your FVD I would probably compare pricing to gutting them to replacing with test pipes. Now if your talking about just going straight pipes all together with no mufflers daily driving is going to kill you. I've got a set of AWE straight pipes too which I bought before my PSI exhaust and they sound bad *** at wot but driving around town normally was tough for me. Major drone between 2-3k and pretty annoying. No cats and mufflers sound great! Now on cold starts the car sounds very raspy but that quiets down after about 1-2 mins once the idle smooths out. You sound like the kind of guy that will like a catless exhaust and I would be very suprised if you didnt notice quicker spool and responsiveness across the board.

 

I have a switzer exhaust on my car with 200 cell cats, thinking of removing the cats but the exhaust is pretty loud now, might be way to loud with out cats... also would not want the drone to get any worse.. anyone have the switzer exhaust without cats here?