CobaltCoupeCrazy

iTrader: (1)

That's right the 2.2L stock exhaust after the resonator is about 1.75" OD. I've been reading about the exhaust being 2.5" until it gets just before the axle and it goes down to 2.25". My plan was to cut out the 2.25" section and install 2.5" aluminized pipe and a Flowmaster Super 40. While doing an inspection of and taking pics of the stock downpipe and cat for Random Technology I noted the much smaller pipe size than the 2.0L. Today I decided to check the cat-back and that's when I made my discovery.

I am waiting for the 2.5" stainless downpipe with the high flow cat from Random Technology that is going to be a direct bolt in replacement for the stock unit (see the thread I started). In the meantime I will need to either purchase a used resonator to axle section from a 2.0L (or 2.4L if it's also 2.5") and then finish the system with 2.5" pipe and the Flowmaster OR I could inquire with Flowmaster about making an aluminized cat-back that is 2.5" and allow for muffler choice. I'd rather use the a stock stainless resonator to axle section, but I've got to find it at the right price to be able to also purchase the muffler, tip and pay for installation.

Just thought I'd make everyone aware of the small exhaust system used on the 2.2L's. Seeing that it is less than 2" an upgrade to a 2.25" or 2.5" system seems like a very reasonable idea.


Scott

zomghax

The 2.4L's and the 2.0L S/C's use the same stock exhaust setup. You could probably find a stock system from the resonator flange back pretty easily considering the number of catbacks that are installed. Would suck to pay for shipping on a bulky, used exhaust though... Hopefully you can find one local. Good luck duder.

IonNinja

the only exhaust systems that were reported to be 2.5" until the rear axle where it slims down to 2.25" is the 2.0 and 2.4 engines. most were already aware that the 2.2L exhaust was somewhere in between 1.5"-2". It is an economy car afterall.

Also I would love for someone to try out a 2.25" exhaust from the header back. I have 2.5" piping (with stock cat) from the header back and the gains were nothing to write home about. I'd like to see how they compare to my current setup to see if its even worth it considering to downsize in piping.

joeworkstoohard

most exhausts won't gain any real power. for the size and average RPM of the motor, the stock pipe is pretty much the right size.

i THINK that the 2.2 2LT cars come with a full mandrel system from the factory. may wanna see if you can find one of those

IonNinja

only problem with that though is I no longer have the stock flanges in my exhaust except for the one at the rear axle so I couldn't simply bolt it on just to give it a shot.

I'm hoping that my nitrous kit will love this 2.5" mandrel bent piping and I wont have to worry about downsizing. But I guess if theres gonna be little to no difference anyway then I wont bother.

CobaltCoupeCrazy

iTrader: (1)

IonNinga: You have all 2.5" piping but have retained the stock 2.2L cat?? That's a big ole choker right there. I'd get a 2.5" cat and see about having a full 2.5" exhaust system. Corsa uses 2.5" on the 2.2L and has said to gain 8-10HP on a chasis dyno for the 2.2L (10-12 on the 2.4 and 12-14 on the 2.0). Magnaflow however chose 2.25" for there 2.2L catback. Personally I think either will be fine but I'm going the 2.5" route.


Scott

joeworkstoohard

in some states it's illegal to replace a working cat.

IonNinja

yes the cat is currently the only stock piece in my exhaust system (header included). The guy I had my last exhaust work done through had a shitload of stock cats laying around so I'm assuming he doesn't care about it being illegal.

in fact he took it out completely to have the piping evened out where I had cut the stock downpipe to install my header. i'll probably go back there one day once I have the funds for a high flow cat.

joeworkstoohard

i can't imagine either piece making a big diff with the cat stock. but then again, really... a good exhaust is able to make... maybe 5 ft/lbs overall... so if you can tell, you're pretty much doing okay

CobaltCoupeCrazy

iTrader: (1)

It's actually a federal law that prohibits the replacement of a working cat. Random Technology posts all of the specifics about legitimate cat replacement on their site. Some of us are lucky enough to live in states that don't have any kind of inspections!!

NS06G5

so if I'm reading this right, from just before the cat it's 2.25" inches then it drops after the cat to 1.75"inches? Right no I'm completely stock, so if I was going to change, it would be to my advantage to do a complete catback exhaust swap up to 2.5" and that would show some decient gains?

Stl06LS

YSUsteven

After the muffler its 1.9" outside diameter.

NS06G5

wicked, that's exactly what I needed to see, highflow catback exhaust for me then, appreciate the help.

CobaltCoupeCrazy

iTrader: (1)

If you think that's a good comparison, you should see them from the end, looking into the pipe. I've got pics of them side by side somewhere.

NS06G5

if you can find them, that would be great!

HackAbuse

Damn, the S/C has a HUGE resonator

halfj99

if he dosnt get the side by side pic.. i will when i do my exhaust