Big Kahuna

Added the Flowmaster 40 Stainless Steel case to the Surf Wagon a few months back and LOVE the rumble!!!

No real loss in mpgs other than me getting on the pedal a bit harder (can't help it).

I do notice the tires tend to bark a lot easier when leaving a stop and performance seems to have taken a nice increase.

Everyone has their own opinions on exhaust systems but here's my opinion on the FlowMaster 40 for the HHR...

:twothumbs

mrjuma

i just got home from san bernardino. it was alittle over 450 miles round trip. got 29mpg, again. thats down 4 from the stock muffler. i wondering if the flowmaster makes the motor run alot different. if the power ban is changed, or maybe it just makes the motor use more fuel.

chingchonger

I use to work in the Automotive Aftermarket industry (6 years) and what we always did when we put on a performance part is to reset the ECU.

1. Drive the car around a bit to warm up the engine coolant to 190 to 200 degrees.
2. Park, disconnect the ECU fuse. Wait 5 mins.
3. Plug in fuse and start. Let idle for 5 mins.
4. Drive it easy at first. 1/2 throttle only. Couple of miles.
5. Take it on the highway and give it some full throttle runs up to 5,000 rpm.
6. The ECU will start to calibrate the modified airflow from the intake and exhuast.

The new fuel mapping should help with the fuel economy as well as power.

mrjuma

thanks, i'll try it tomarrow. i have a hayabusa, and it needs to be remapped when every a change is made.

chingchonger

I would reset my ECU after each oil change. That is to take in consideration of the different gas that is formulated as well as the change of weather for each season. But that's just me. After every performance mod should be fine for most people.

mrjuma

are you talking about the Engine Control Module? fuse number 42.

johnbrum

So are ya'll just replacing the muffler or doing a cat back system

STR8SiqHHR

I have a Flowmaster Thrush Turbo, key word TURBO. Now let's discuss our muffler types. The Imco 924 is a Turbo. The Flowmaster Thrush is a Turbo, the Cherry Bomb Turbo and DynoMax Super Turbo are all similar in design. The Delta Flow 40 series is a 2 chambered muffler, the 50 series is a 3 chambered both similar to the DynoMax Ultra Flo. They use chambers that bounce exhaust gases back in forth between chambers before leaving the muffler, some are designed to be quite but most aren't. Turbo mufflers on the other hand are packed with steel wool to absorb some of the exhaust sound, and usualy consists of 3 tubes surrounded by steel wool. All Magnaflow exhausts are Straight through, hence their slogan. They are packed with wool for resonation but it is straight through no chambers no tubes. So with a Magnaflow expect the neighbors to be a little upset. I have experienced no changes in gas mileage unless I jam on it. Not that loud either compared to when I first installed it due to resonating, just a deep smooth tone. I'm not sure, but back pressure on the Delta Flow 40 is more than likely not equal to the Imco being it is a turbo. I know with a Magnaflow back pressure is extremely decreased because of the straight through design. Rumor has it the Ecotec likes hot air and a little bit of back pressure. Only way to know for sure is to Dyno and compare results against the Imco which SoCal can probably get you. Remember poor gas milaege can be contributed to a number of things though, under deflated tires, dirty oil (believe it or not), you running the A/C all the time or just sometimes (the A/C compressor in the HHR is a hog and power will decrease significantly as well as gas, also where you buy gas from and what octane. Out here in SoCal high gas heaven 91 octane is out of the question so I go with 87 and STP 0-60 every 4 fill ups. I only buy gas from Shell or Chevron if I'm lucky and it is reasonable Unocal 76. Stay the hell away from Arco, Citgo, Valero, USA Petroleum and who ever the else you have never heard of. Now I'm assuming you have a 2.4, for the 2.2 octane may not be an issue but gas supplier still applies. Hope this helps.

laborkei

Big Kahuna,

The Flomaster 40?

I have a Flomaster 50 on my GMC Yukon, and it gives a nice rumble, but does not take away from stereo listening. Not sure if you are familiar with that model. How's the 40? You have my curiosity... Is it loud enough to be a distraction, or would a 50 be better.

Thanks,
Keith

chingchonger

Yeah. Engine Control Module, Engine Control Unit, same thing.