Ive been thinking of what i want to do next with my 911. i have my exhaust and will get the evoms intake, and have been thinking of doing headers, or cat bypass pipes instead of the headers.
Questions i have are:
1) will cat bypass pipes give me a check engine light?
2) are there any headers that dont take away low end tq?

What do you guys have for a set up/recommend?
Does todd at protomotive do NA 911 chip reflashes?

 

I spoke with Jay at Fabspeed a week ago when I was thinking about getting the cat bypass pipes and he warned me the cel light will most likely come on ! They seem like a great way to gain some hp but but your gonna have to deal with the cel light !

 

yes, you will probably have a cel. not to mention if you combine those bypasses with other exhaust mods it's abnoxiously loud. the cats absorb a lot of noise and without them it really starts to sound like crap.

probably not on the headers. that is the nature of header tuning. you give up hp in one part of the power band to pick it up in another part. i think it would tough to have the best of both worlds and pick up significant HP on both ends of the powerband.

lots of people do NA flashes. frankly, i wouldn't bother. do some mufflers for the sound. everything else is wasted money with probably no "real" perceptible gains. picking up 25 HP or so on a 320 HP car isn't going to be noticeable. if it wasn't so expensive on our cars, i'd say do it anyway just cause... however, bang for the buck, nah. $1000 for the flash. $1000 for a set of mufflers. $1000 for some headers. $1500 for high flow cats another $500 for a good intake. ad another $500 for labor and tax. 5.5 g's later and i'd be surprised if you picked up a .10 of a second in the quarter. just spend the 10 grand and get the blower if you want to really improve the performance. everything else will just be a tease.

 

Couldnt have said it anybetter, then again, I like to tune, Id spend the 5k on parts, then saving up for a blower soon

 

all my questions answered in one post....I will leave my NA 996 exactly that...NA. Thanks!

 

just don't forget to do mufflers and suspension stuff if you choose to. those are two areas that benefit greatly over stock. the car sounds so much better with a decent set of aftermarket mufflers.

 

Cool...the car came with Mille Miglia exhaust..and the Row M030 setup...so I should be good to go I think!

 

Regarding the CEL problem; has anyone tried this type of product? http://www.o2sensorsimulator.com/

Seems like it would do the trick.

 

But the 10Gs for the blower is just the start!! You could easily double that and more.... These cars are like bikes, they're never done.... But, I agree with the mufflers - the FIRST thing you should do is uncork the motor. It's all down hill from there

 

well i already have mufflers, and will def add an intake, headers im not sure about yet. if i can get a good deal for a good price then ill do it. reflash is out, but i will be doing 18" light wheels(iforged or ssr GT3), dropping the car, and adding in GT3 seats and that should be it! the weight savings will prob give me the best improvement. thanks for the help guys!

 

I was hesitant at first about getting headers, but then now that I have em, I wouldnt replace them, so much more higher end grunt and no more drone in the cabin. The engine defintely breathes so much better now.

Ask Dan @ Vividracing.com about headers, im sure he will hook you up. I get most of my parts from him. And never had a complaint, everything performs the way he describes them to be.

 

I have headers, exhaut, cat-bypass (mainly cause it was too quiet for me) uni-chip computer, stock intake (just installed K&N last night) and my car put down 275whp last fall (290 BHP on the 3.4L). He needed some tuning help at the time and the shop did not have time. I was ok with it. The car will be going in soon to get dialed in with the K&N installed and the cat bypass. THe great thing about the uni-chip is that it is programable.

video of cat-bypass setup
http://video.google.com/videosearch?q=cat+bypass&hl=en

 

not for nothing bruce, but how can you stand the header, cat bypass, and muffler combo? i had that setup on my car for a day. it sounded like ****. way too loud and raspy, and not in a good way. more like a honda civic with a big rusty hole in the muffler i think the cat bypasses are way too much if you are using any other exhaust mods.

as a point of reference, my stock 996 made 275 rear wheel HP on the before dyno run. after the supercharger and header install, it made about 425 rear wheel hp.

 

I have the stock exhausts, fabspeed headers and the cat bypass. I HATE the sound. I am pulling the bypass off right away after I get the car back from the body shop.

I have since ordered the agency exhaust and will run stock cats, the agency mufflers and the headers. I think that will make me happy.

The fabpeed bypass did give me a cell and caused the car to idle a little funny. Not reccomened unless you are doing track days only. The sound in the car is fine, insulation is good in the 996. But I couldnt stand how it sounded when a friend drove my car....EWWWW

 

This is how it played out with me. I put gemballa, exhaust and headers, evo intake and GIAC flash... noticed a small performance gain as mention by DD, then decided to go the S/C route...all of the exhaust mod are a plus for the S/C setup. I got a partial refund for the GIAC FLASH and I sold my air intake as it is a popular mod...all worked out well in the end, now what about sport cats... its gotta help out the blower, right?