SLP Powerflo Exhaust

**04gpgt** · 04-27-2009

I recently installed a SLP PowerFlo exhaust system on my Grand prix GT2 along with a K&N intake...I am experiencing a lot of cabin resonance at low end RPM...I am actually quite annoyed by it. I was wondering what suggestions anyone would have to fix this. resonator i thought..or would a new hi flo cat fix this issue? the car sounds excellent outside the car under low RPMs but it gets to ya after awhile on the inside. Its added the HP and torque and i love it, but I feel i spent 600 bucks on something that almost sounds as if i cut my mufflers off. Thanks so much!

Also I was wondering if I cant fix this issue...then what would make my car have more of a V8 rumble...it still has a V6 rumble to it seeming a little softer than what i am looking for. thanks so much.

**99prixgt** · 04-27-2009

Originally Posted by 04gpgt

I recently installed a SLP PowerFlo exhaust system on my Grand prix GT2 along with a K&N intake...I am experiencing a lot of cabin resonance at low end RPM...I am actually quite annoyed by it. I was wondering what suggestions anyone would have to fix this. resonator i thought..or would a new hi flo cat fix this issue? the car sounds excellent outside the car under low RPMs but it gets to ya after awhile on the inside. Its added the HP and torque and i love it, but I feel i spent 600 bucks on something that almost sounds as if i cut my mufflers off. Thanks so much!

Also I was wondering if I cant fix this issue...then what would make my car have more of a V8 rumble...it still has a V6 rumble to it seeming a little softer than what i am looking for. thanks so much.

Nothing will make it have that v8 rumble. Welcome to the world of the 3800 V6. Ive gotten used to mine after a while

**04gpgt** · 04-27-2009

I know I wont have the actually V8 rumble. I am used to the 3800. Ive had 4 cars with the 3800 in the last 8 years...I just want a more throaty sound from it. I was going to get a new downpipe with a high flow cat, but wasnt sure about what it would do for the sound and performance. Also..since i put on my K&N my car temp has been a lot higher than i really want it. anything i can do about that?

**boosting98** · 04-27-2009

180 thermo. and i would do the downpipe w/ cat!

**04gpgt** · 04-27-2009

You got a link where i could get a good 180 thermo? Or whre I could get one? thanks. And ive been reading a lot about ZZP and I wondered if this is the best bang for my buck? I was going to get a SLP downpipe with highflow, but want to get the best i can get.

**blueguy** · 04-27-2009

Reason being your temps go up is because the K&N is a ****tastic intake system. Make your own...much more cost effective and the performance gain blows that POS out of the water. You can get a 180* or 160* T-Stat at any local auto parts store you just have to ask them for it. Get a catted 3" ZZP Downpipe. The reason why your car is doney and has a V6 rumble is that reason...the 3800 is a drone, raspy pitched motor...and the SLP Catback is rasp city from the ones I have heard. When/If you get a cat, it'll make it sound a lot better probably. SLP's Downpipes are only really worth it if you go and get the actual SLP Header System...I've got Pacesetter's and I like them and I did a custom exhaust with a stock GM resonator with Flowmaster's. Most people hate them...I love 'em to death...I had them with the headers and no cat/res...boy did it sound like s**t...put the stock res. back in and the car sounded awesome again

http://www.youtube.com/watch?v=Il0bR...e=channel_page

I recommend and headers, they are awesome

**Bio248** · 04-27-2009

i would put a giant glasspack in the exhaust and call it a day. it will give it a little more throaty sound and might take out a little bit of the drone for you.

**99prixgt** · 04-27-2009

When i added my zzp dp with magnaflow cat, my exhaust got way raspier but, i actually like it lol

**04gpgt** · 04-27-2009

after just spending 600 bucks on the exhaust i really dont want to do a lot of changing to it. If i added my stock resonator to my system would it help tone down the sound a bit? If so i would probably do that and add a downpipe with highflow. The K&N i have had in for about 4 months and seeing as I paid for it already i will probably keep it in. I know now i want to get the 180 thermo, It is probably an easy install, but like i said i am new to messing/modding cars i wouldnt really know where to start with that...feeling quite embarassed about that though seeing as my family owns a huge GM dealership haha. any help is much appreciated. :-/ I just dont wanna keep messing with things i already have installed like the exhaust so I want whatever i do to be a one and done. I dont want to go to the extreme either and install a turbo or something ridiculous like that...just simple mods that set my car apart fom the others. headers are probably out of the question, but powerlogs might be another install i would like to do too. As you can see i have a lot of high hopes for my car..just a matter of getting there, and doing it right the first time. Thats where the help and experience from this forum comes in. I do appreciate all the input and any more would be greatly appreciated. thanks again!

Tim

**blueguy** · 04-28-2009

Thermostats are easy to install...2, 10mm bolts hold the housing on. Unbolt those and prepare to lose a little coolant, twist the hose and hold it back with a bungee cord or something...pull out the old T-Stat, and drop the new one in...and reverse order

Just get a 3" Downpipe and a Front PLOG then...the rear one is fine from the factory...just make sure to have some new exhaust bolts cuz from what I have seen they always break...and for the stock resonator...that is up to you...it might...who knows.