Exhaust Backpressure and MPG

Hey folks...

I have read a lot on the postive effects of reducing back pressure in the exhaust system to boost mpg. And most after-market mufflers web sites tout the reduction in backpressure. With the newer emission engines [not 2007 but previos generation] with a VGT and EGR is there not a backpressure loop created in order to get sufficient pressure build up for the exhaust to be injected into the clean air intake stream. So the VGT, with its contration and expansion, is now the backpressure "gatekeeper" and not a muffler?

My Q's?

Does reduction in backpressure in the exhaust work equally on newer engines [2004-2006] as on pre-emission engines??

What are the experience of those folks who ripped out mufflers and gone straight pipes as it realtes to MPG? Please include the year of your truck and engine in the reply in order to see if it worked on the newer engines [eg. like 2003-2006 Cat's with catlytic converter in muffler which should cause tremendous backpressure].

Thanks

Craig

 

Thanks for the response.

What I am hearing is backpressure improvements in pre emission engines [pre 2003] seem to be effective all the time.

The 2003-2006 engines you can break them down to Cat ACERT and the balance used EGR’s with VGT.

Cat adopted a muffler with a catalytic converter. Which is a huge constipator. Given CAT also has an advanced ECM I was wondering if the ECM would need adjustments or reset if you changed backpressure. You folks seem to indicate your improvement occurred without the need for ECM reset/adjustment.

For the balance of the mfgrs they used an EGR system that requires the VGT to build-up backpressure so as to inject exhaust into the high pressure clean air intake. Would love some feedback on these.


Regards,

DCW