ive decided to put the 40 series on my truck and i was wondering would 2 inch be good or 2.25 be good ? ive heard 2'' pipe is best because it makes more of a back pressure resulting it sounding better. what would you reccomend? ive heard 2.25'' sounds the best but wondering does anyone here have 2''? thanks.

 

i think most everyone goes with 2.25 like the rest of the piping...

 

ok cool, thanks Justin. just wanted to see if anyone had experienced with this size of piping.

 

It is best to have a bigger pipe going into the muffler and smaller one coming out, that keeps the velocity up. Is this a single out application? I would say go 2.5 in and 2.25 out, or 2 out if you are going duals. You can always put bigger tips on the end, that will give it a deeper louder sound by acting like a megaphone......

 

ive heard with my 3.0 to go 2.25 all the way through though. 2.5 into 2.25 sound any different?

im going to be running duals.

 

I run 2.50 after the cat, no muffler but it sounds great, I will be replacing the muffler very soon (tax money?) and I will probably keep the 2.50 after that and run it to a 3in tip like usual. I also have the 4.0

 

ok so for the best sound go single in 2.5 into 2.25'' dual out ? who has this set-up ? and what you think ?

 

Do you have a local shop that does dyno tuning. He can tell you what is the best setup for most componenets if he has done a lot of dyno runs. Many time what we or others think isn't what the dyno tells.

 

that is true , but i really just want the best sound possible not that honda civic sound with a coffee can on it. know what i mean ? and a lot of people here run a similar set up so i just want to know what is the best? the single in im not sure about, but the dual out i know people said 2.25'' gives best sound/performance.

 

It is hard to tell you what the best sound will be, I love my flowmaster on my 4.0 with a 3" tip, it is nice and deep and idle and under 2000 rpms. No matter what you get, if you want it deep, you will want something like a 3 inch tip on the end......

 

you have a sound clip of your exhaust graygoose?

 

on my 4.o i cut off the flange after the cat and ran 2.5" tubing all the way to the 3" inlet for the flow 40. right now it is dumped but i plan on welding up some pipes that exit infront of the pass. tire. the flow is si (3")/do(2.5"). right now it sounds great, nice and very deep at low rpm's and i was surprised that there was only a very slight loss in lower end torque (but the bigger pipe made up for it every where else). and i found that from that stock flange back to the muffler the pipe was 2" OD. everyone else here seems to have 2.25" stock...huh