can anyone tell me with a mostly stock car or just a few mods what they noticed when they kept a stock exhaust just just put in a straight pipe where the cat was. I'm thinking about doing it and just want some reviews. I heard lil extra ponies and better gas mileage. I don't have to worry about emisions where i'm at and i'll be putting it back in next summer when i get a 2.5 tsudo and i turbo it. Also does it make it any louder? kinda hope not...

Thank You. Also i do have gms fancy muffler and an air intake. i have 500 to spend and i'm thinking 2.4 intake mani and tune. also any more reviews on trifecta's tune including how i contact him :d thank you.

 

Removing your cat will make your exhaust much louder. I have the 2.4 mani and it makes a huge difference. I just want to get a 2.4 TB and a tune and thats it...

 

what about the catback delete did that improve horsepower and gasmilage?

 

Some say it will gain a little but it all depends. I think only a TC car can benefit from catless and any car making alot of power. I would say keep you cat on. IMO

 

alrighty thank you!. how was installing the 2.4 mani did you do it yourself? otherwise if you brought it in and how much was it. i have an 06 i believe i need a spacer and a 1/2 inch hose. how long does it take to do? also what kind of wrenches are needed. I'll keep searching too, or if you are able to find one and link me that'd be awsome too. I'm new to forums so yeah sometimes i have difficulty finding stuff.

oh and does anyone know if i went hptuners how much it is, i hear you get better gains from it then trifecta, but who would tune it? i have no shops where i live. would an average joe willing to learn be able to figure it out?

 

#12587878 manifold
#12589516 pvc seal
#12600729 tb seal
#15855993 hose
^^GMpartsdirect.com
http://www.crateenginedepot.com/stor...P1820C137.aspx
I reused the individual intake runner gaskets and just got a hose from the automotive store but the one up here is from the 2.4SS so it would fit. So I only ordered the first 3 parts. I only remember using a 1/4" drive set w/ ratchet. I would use a torque wrench if you aren't sure if you'll break the bolts but I just tightned them up real snug using one hand that way you don't over tighten them.

 

HPTuners wont work for 06's. it only works for 07s and up. Trifect is your only choice of tuning unless you can get psykosteve (i believe thats the correct way to spell his name) to do it for you.

you can contact vince by goin to trifectaperformance.com, i would give you the direct number but for some reason i cant get on the website right now (damn govt computers!!!)

 

Will a catalytic converter delete throw a CEL on an '05? Is the oxygen sensor before or after the cat?

 

cat delete will throw a cell if you do not relocate your second o2 sensor back into your exhaust pipe somewhere.

NA cars NEED back pressure, unless you have crazy cams with a Huge duration. Removing the cat and or just muffler will not gain HP or TQ just lose some, and **** with your throttle response. Having back pressure allows your car to continue to pull at higher RPM's unless you have boost like me then back pressure is not an issue.

Either way you look at it, it's a waste of time, and could damage the motor. If you have to free of a flowing exhaust on a car that's Naturally Aspirated with no major mods you could potenially suck a valve or bend one... And for the record it makes the 2.2 l61, and lap sound like **** when you disconect the muffler. REALLY RASPY!!

 

keep the cat, your not turbo'd or putting down at least 300+

 

this is what i would do in your situation.....

1. since your turboing your car....get a high flow cat and a catback exhaust. (it will benifit you later on aand it sound pretty good.)
2. also get the 2.4 mani and T.B

3. get trifecta. you will need it any ways if your going to put the 2.4 mani and T.B, and turbo.

 

i read a review on removing the cat and it said that removing the cat (this was done with a cavy) was good for 7 hp on the dyno, but they also tested a high flow cat and that was good for 5 hp. you would not really notice 5-7 hp. if you do you are starting to get into a self fufilling prophecy. but hey, every bit of horsepower counts, hope you liked my 2 cents