Lost low end torque with catback?
Thread Starter
|
Member
Joined: Jan 2007
Posts: 79
Likes: 0
Lost low end torque with catback?
I've had a Magnaflow 16612 installed on my 07 with 5.4 for about 1 year. Over the course of that time, I have swapped the OE and cat back systems back and fourth to see what gains there were other than sounding better. My goal was to gain more power when towing. Here is what I found...
With Catback:
- About 1-2 MPG improvement both highway and city driving.
- Improved passing power empty and towing. The engine seems to be able to rev up easier / faster.
With OE exhaust:
- Loss of MPG empty and towing (no surprise)
- Improved low end torque most noticable when towing.
My truck has noticably more low RPM power when towing with the OE exhaust in place. I can tow loads using OD with no or very little gear hunting and the converter stays locked but with the Maggie installed, I could never use OD and even driving empty, the converter would unlock more with small hills.
Does this sound about right when a person puts on a freer flowing exhaust? I was just surprised to see this.
With Catback:
- About 1-2 MPG improvement both highway and city driving.
- Improved passing power empty and towing. The engine seems to be able to rev up easier / faster.
With OE exhaust:
- Loss of MPG empty and towing (no surprise)
- Improved low end torque most noticable when towing.
My truck has noticably more low RPM power when towing with the OE exhaust in place. I can tow loads using OD with no or very little gear hunting and the converter stays locked but with the Maggie installed, I could never use OD and even driving empty, the converter would unlock more with small hills.
Does this sound about right when a person puts on a freer flowing exhaust? I was just surprised to see this.
Agreed...i can say with my custom bent magnaflow system and intake my power range has def shifted.
Once the system was broken in i can say i have lost some low end torque but have definitely gained mid and top end as i can tell the truck can breath easier now. I'm hoping with some other bolt-ons like underdrive pulley and efans i'll gain back some low end to even out the power band.
Once the system was broken in i can say i have lost some low end torque but have definitely gained mid and top end as i can tell the truck can breath easier now. I'm hoping with some other bolt-ons like underdrive pulley and efans i'll gain back some low end to even out the power band.