oowah

I got my ss/tc in the spring (April) and have done a few mods, just appearance/comfort stuff really. So now I want to get plans for some performance mods over the winter and get it all tossed on once the nice weather returns.

So what do you guys think is my best route to take?

Plan one: Get GMS1, upper charge pipe and catted downpipe

Plan two: Spare ECU, HPT custom tune (local tuner), upper charge pipe and catted downpipe

I want to stay away from intakes because of the lack of stability I have seen from other peoples' experiences on the forums. I know some people have had good results, but I really don't want to have to worry about **** working or not. I'd like keep my warranty since my car is pretty new still, but I realize that if there is something wrong that was caused by my mods I'm going to have to absorb that cost. I think my plans are tame enough that I won't go blowing any turbos or anything anyways This car is my DD, but I'd like to take it to the drag strip next season.

Any opinions or advice on mods?

TrevMo

Plan 1 minus the catted downpipe...if you are going to stay catted, it is pointless to replace....I have the Injen piping and GMS1 and I'm perfectly happy! And I also have my full warranty intact!

oowah

I thought that the cat had a pretty minimal effect on the flow?

And yeah, I was going to go for the Injen piping as well

TrevMo

I don't know...everyone talks about how restrictive the stock cats/downpipe is...but I can't imagine it makes that much of a difference...if you are going from stock to catless, you might see more gains...but stock to high flow...probably not worth it in my opinion...

blackbolt89

from what i had gathered the cat doesn't really free up a ton of HP if you go catless, but flow will definately be reduced with a cat. whether or not it's a ton of flow i can't say.

oowah

Fair enough. The way I understood it was that the downpipe was the big bottleneck of the exhaust system on the TC, but maybe that was just because of the cat. I'll have to look into that.

john_boy1987

the warranty issue you shouldnt worry about, cause they have to prove all the parts you put on the car, caused it to mess up.

gdubs

iTrader: (32)

The DP is a giant Bottle Neck. When ur stock and only pushing 115-17 psi.... its not so bad. But push another 9psi through it and u get alot of restriction

swazzees

hmmmm im in the same boat as th e OP
was waiting till spring but my plan was hoping for 300 whp

I was thinking

GMS1 and catted downpipe and some sort of airbox mod.


what i hope happens is

GMS2 catted downpipe and get 300 whp and 330 wtq

TrevMo

I guess it just depends on your reference....look at the stock system to just about every other street legal car...it is pretty impressive what GM did with it...Unless you are going for 400HP+ or you just don't have anything better to do with your money, the stock system should be just fine (in my opinion)....

oowah

Yeah, I agree the stock exhaust setup is pretty solid. I think a downpipe will help free up a few ponies and make the exhaust note a little more distinctive. I believe the stock down pipe has two cats (anyone wanna confirm that?) so one high-flow should at least be a little better flowing, and add in smoother bends and it should be worth something imo

Yeah, I've got roughly the same goals. Looking for something in the neighborhood of 300whp. GMS2 would be nice, but I have a feeling that might be a while. lol

cobaltltblue

I personally tuned a friend bone stock. good gains. BUT when we added the ZZP DP it was a noticable diffrence, THEN i retuned for the DP and even more power was found. I think the bigest thing we noticed was the boost came on quicker 0-20psi. No Dyno to prove anything but my ass thinks so! LOL

swazzees

lol all the intakes are making the air super turbulant I guess......
soooo I would like to se a GMPP intake that can beat the stack and give it a better sound and livin up the turbo and blow off sound.


The stock DP has 2 cats......i seen that a while ago but never remembered till you mentioned it




A high flow Cat in a clear image DP or ZZP or Hahn and stage I im hoping to be bout 295 ish


sounds super duper for me

its all i need
any more will mess with my DAily driving habits

oowah

Yeah, at this point the only intake I would put on my car would be a GMPP one because i think if anyone was going to get the proper R&D done to make it work it would be them.

And yeah, I was looking at getting the ZZP catted DP. I just want enough power to go to the track a few times, and leave some rubber on the on ramps

swazzees

nice
im not sure what the best is....

CLear Image spends time on research and development......cost is a bit more but i think i may go that route.......need to talk to ppl who know i guess.

zzp people say is good and cheaper and good customer service....


so I have no idea

Hahn is always good i guess unless you buy an intake then it bytes

lol

oowah

Yeah, I think in the end a lot of it just comes down to preference. I mean really, it's not like there's any major technical differences between the brands for a product like this.

swazzees

nope
i have ammisions testings to pass in a couple years thou....so i need a cat to help with that too

lol

oowah

Yeah, I hear ya. Stupid drive-clean. What a rip off

SSlobalt

Yeah...................good luck with that.

austinss

You could always gut your factor dp so it looks stock. I really want to do this myself so I could save a few hundred bucks but I keep hearing I'll get a CEL, yet people buy catless dp's all the time with no CEL.

swazzees

oh i missed it your from ontario too\



where bouts?

and I would skip the sprae ecu ****....headaches
I know a dude from T.O hes HPT and boosting 21psi...its fast as **** and GMS1 is approx 21psi too

so I thinkit will rock especially if they come out with an intake

Im near london ontario

oowah

from oshawa. Foo Fighter on OCC... i think you're on there too, yeah?

swazzees

ohh yeah im swazzees over thier too
I make ky meets in Kitchener almost every week...takes me about an hour to get there.....

never hit a monthly yet, thou ive tried numerous times.
Im one of the few whites
only ever ran into one other white coupe and one white sedan


I thionkk seriously thou the DP is the bottle neck in the system, looking at it at work ( GM store )
it changes size many times and i reallt do believe it has two cats...

I hope a CIA DP can get me thru the drive clean.......

rukkee

iTrader: (3)

When I installed my catless down pipe the gains were noticeable . They say it's worth 15 hp . The stock down pipe is really restrictive , 2 cats and a crush piece where the o2 sensor installs .

The sound of a catless Dp is just an added bonus , it sounds almost stock till you get on it .... has a nice crackle and pop to it when you let off as well. Another nice thing is with the angled o2 bungs ...there are no codes at all , it's like you never even changed it to the computer.

swazzees

what brand name yo go with?