wellcraft290

So if I keep the cat and get rid of both mufflers will it be too loud or just once you get rid of the cats and both by passes?

jim_l

i would suggest bypass only the primary or the secondary. bypassing both seems a little loud for most people and maybe some track if you do DE. i did the primary bypass, stock cat and secondary. loud but not crazy. i have run the car with just the cat and its way to loud for me.

wellcraft290

So jim you run both bypasses? I will keep the cat just for inspection purposes. Definately doing the secondary just curious if I should do the primary at the same time.

jim_l

i currently have the primary bypass only. and happy

68CGPlt

I have a cup pipe (primary bypass) with cat installed and am happy with the results. I have never tried the secondary bypass so I can't comment on it alone or in combination with the primary bypass. I like the sound (not to loud at all) and there is a perceptible change in the nature of the engines response. I have no regrets.

wellcraft290

Ok why you pick primary over secondary?

BlueHeeler

Weight loss from the *** end is why a primary is better than a secondary.

From what I have read here the primary vs secondary give similar performance, but the secondary (g-pipe) is louder.

I have a cup pipe and for a street driven vehicle it sounds perfect IMHO.

joey bagadonuts

Not to start a flame war but I prefer the sound of a g pipe. Had both on my car and, imho, the cup sounds like a wet fart while the g pipe is reminiscent of, perhaps, a motor boat. Neither gives a raspy, flat six snarl but it's definitely more sound over stock. A cat bypass will give your exhaust some *****. It adds a deep thump to the symphony, kinda' like turning on the sub woofer.

Get the cat pipe and keep the stock part for inspections. If you think a muffler is restrictive, just take a look down the barrel of your stock cat.

$0.02

wellcraft290

How hard is it to install and uninstall the cat pip? well going with the g-pipe found one used. Just thinking if I want to do any more or just see how it works.

BDHo

how much louder is removing the cat while keeping the secondary muffler assuming the primary muffler is already gone?

joey bagadonuts

How much louder along with a cup or g pipe? Hard to say. It's like going from a solo act to a duet--decibels don't double but your exhaust will be louder and more complex. The sub woofer analogy is the best I can think of. There's more boom and low end growl.

As for ease--that's also tough to say. Essentially, you need to remove the four bolts which attach the cat to the heat exchanger and the seal/clamp from the primary. Liquid Wrench overnight will help and you should probably replace the cat/HE gasket. The challenge will be your O2 sensor. I'd recommend buying a second one for your cat bypass to simplify matters.

If you want to transplant the O2, however, please use the right tool: 22mm wrench not an adjustable. You should also warm up the cat but please be careful not to burn yourself. Extracting your sensor from a cold cat is virtually impossible but I've had success--three time--by removing it from a hot one. A torch can also be a useful extraction aid.

There are also rusty speed nuts securing the shields which may prove problematic. The whole thing can be quite a chore but if you have the right tools and understanding going into the operation, it's very doable. Please search cat bypass for some other useful workarounds which will get the original off.

Not a simple swap but well worth it if you're looking for a bit more sound and (possibly) power.

wellcraft290

Ok thank you all. Will start with the G pipe and see what happens and how it sounds.

kgorman

I have the Dansk G pipe plus a cat bypass from Fabspeed. The exhaust note is awesome, sounds deep and throaty and rumbly. You save a bunch of weight as well, not sure exactly how much, but it's a lot.