Installing the Donaldson Muffler on the MBRP turbo back straight pipe exhaust. Question is which way does the muffler go ? This may be a dumb question but I have searched all over to see which end of the muffler goes toward the front and which end towards the rear. There is a vortex end and then just a straight through end. Any suggestions?

Donaldson Muffler M090544

 

Mine had an arrow that said inlet on it

 

Thanks, I will check that. I looked around for an arrow or inlet marking but just pulled it out of the box after work for a minute. Appreciate that!

 

These mufflers are meant to be mounted vertically. With that being said, they are made with one end rounded out for rain to bead off. The dented in end is the inlet.

 

Also a coned baffle in the inlet end on mine.

 

mine also had an arrow - but i ignored it. i looked through the muffler to see which way is best. if looking through one end you will see some cones or baffles that will 'catch' air. if you look through the other end you will see it is more free flowing.

i ignored the arrow and chose to mount it in the more free flowing fashion. if needed, i could just take it out and turn it around to quiet it down a bit but i really don't think it is much louder than when it was stock.

if you follow the arrow it will be quieter and less free-flowing.
if you mount it against the arrow it will be a bit louder but more free-flowing.

 

dome side is the outlet side concave side is the inlet side.

 

And remove those cone baffles.... A long heavy bar works great! I took mine out as soon as it came out of the box and it is as quiet as a stock muffler.

 

If I mount it backwards will it really make a difference in sound and air flow I would like it a little louder.