thehappyfrog

Hi all! My supercharger and intake manifold came in last month, I'll put them on and document the install at the end of this month.

While I'm doing it, I wanted to do some simple upgrades to the exhaust system and was looking for suggestions. What do you all recommend? I've read headers, downpipe, and catback exhaust but I wasn't sure what or where to buy some good ones.

Looking at these:
05-10 Chevy Cobalt / HHR / ION Racing Downpipe CatBack Exhaust Replacement Outlet Piping

05-10 Chevy Cobalt 2.0 / 2.2 4-1 Design Stainless Steel Exhaust Header Manifold - Black

As always thanks! So much info out there, but you folks are always the best resource.

RF2

Your going to have fun with the supercharger.
You might consider getting a Dual Pass kit from ZZP for your heat exchanger.

That Ion racing down pipe is just the flex pipe section. If you look closely it is the crush ring type. I had one till I tried to get a new crush ring. Not easy to get. I changed every thing to the Trubendz system.
I used a ZZP shorty header. They stand behind their products. Mine cracked and I sent it back and had it back in just a week.
TruBendz has a 3" and 2.5" down pipes with reinforced flex pipes for supercharged cars. I have the 3". They also carry cat back pipes from 2.5 to 3." at very good prices. They will custom bend and build your pipes.
Muffler is your choice. You will need a little back pressure to keep the bottom end torque, but you want it still to flow to get the top end.
Consider a water meth system to help knock.
Good luck.

hhrfreek

Get a shorty header and downpipe from ZZP. Don't change the cat back. There are no gains there...just a lot of noise.

CorvetteMongo

I've spent some time the last few months researching exhaust mods as that is going to be the only performance mod I do on that anemic 2.4 in my panel...what surprises me more than anything is the header manufactures even admit that their headers have little or no performance improvement on a stock/near stock engine. I will probably use a header though...just cause it looks faster...

A better down pipe and a good low restriction cat with a good cat back system is the best bet. What you need to see in the exhaust system is not only larger diameter but smooth bends inside...if the are wrinkles where the pipe has been bent it affects the flow and decreases performance. Buying from any well known manufacturer should give what you need.
Don't be afraid to call the manufactures Tech/Support lines and ask questions.

hhrfreek

I installed a header/dp on a stock 2.4l. My fuel economy increased and it was very noticeable that it had more power. That combination works great and would be perfect for a SC.

flamarallenjr

Dyno time is the ONLY way to know. That is to establish the HP and TORQUE numbers before and after.

hhrfreek

Butt dyno is accurate enough in this situation. It is immediately noticeable. There are numerous ways to measure differences on the street. MAF readings are a good indicator, but acceleration data is the best method.

Vinnie_Madrox

Which header/dp combo did you use?

hhrfreek

Bad Mab shorty header with ZZP 3" catted downpipe. ZZP now makes a shorty header so you could get both from them. It sounded great too with stock catback.