I don't conclude exactly what you do....

Air with out Exhaust does not help that much.

Air and Exhaust helps a bunch, but no miracles. There are other added benifits like quicker throttle response and potential small MPG increase. I did the banks pipe because I could. I spent $300 or so and in my opinion ended up with the best exhaust possible. The downpipe maybe a little over kill at this point, but may pay off more later with more power mods. I didn't want bling bling stainless under the truck that you can't even see so I did not see the benifit of buying a $400-800 exhaust. No aluminized exhaust under $400 includes a true 4" system. So with a little creativity I got exactley what I wanted for less money. The Donalson muffler has no drone (maybe a tiny grunt at 1500 rmps...but the truck is almost never at that RPM with the foot on the pedal) and really sounds nice. I am real happy with everything I have done so far...

 

There is a point where an exhaust system is "large enough" for a specific rig. Unfortunately, I don't know what that is. In other words, you could put a 8" exhaust system on a rig and get zero benefit over a ??? (3", 4", or?). I like the idea of the true 4" system such as you have and I will probably go the same route you have. I was just pointing out that others on this forum (most recently AKram) have seen very little benefit from the addition if the Banks downpipe. This fact shows me that the true 4" system is probably overkill for mild modification.

However, like you, I plan on adding significant power "down the road". In fact, I want to add a larger turbo very soon. At that point, I'll put a similar system on my rig as you have. When you say you spent $300, was that for the complete system including the Banks DP? If so, I'd like a parts list

 

Most say 4" is ideal...for 300-500 hp. I plan to try to get to 400.

I spent $200 and change for Banks BP and new 4" v-band
$100 for 6.5' of 4" aluminized pipe, donaldson muff, and three ss band
clamps from the local Stewart and Stevenson

I cut the stock system free right after the muffler where the pipe just turns 4"...bolted up the new downpipe, flared the 4" pipe at the local muffler store for nothing and sliped it on the downpipe, cut 6" or so (what ever was exactley needed to fit) off the 4" pipe, slipped the muffler in tight, tightened the three band clamps, cut off the oem hangers, rebent and welded them onto the new system where they needed to go to utilize the hangers, and presto. $300 and change, 1-1/2 hours of work. You will need a MIG welder (or TIG if you are a stud), a couple of wrenches for the downpipe and clamps, a pry bar to get everything slipped together, a cut off wheel or grinder, and a tape measure.

 

Thanks for the info, that is a great set-up and a great price too.

 

Penciled numbers,..mine got 1.5mpgs better with it on 50% as opposed to stock. that's on a 600. Also I think that free upgrade to timing on that box was per EEngel and was on boxes purchased from or through Percision on the east coast. I don't know that all distributors are offering that upgrade free, fyi.

 

If I remember right, Doug had figured out how much restriction (or maybe it was flow) a 3.5" pipe imposed compared to a 4" pipe during an earlier muffler discussion. Maybe when he sees this, he'll chime in with that info again. On the Banks DP, some folks have posted seeing benefits, so maybe there is, just at a much higher horsepower level than we are at. My goal is 450hp (and yes, I will stop there), so I have a little ways to go before my truck will handle that. The Banks DP will have an opportunity to prove itself yet (don't have my hopes up). I suspect the benefit will not be a measurable difference, at least not one that is worth what they get for that sucker ($$$). I suspect that if your going to stay below 500hp, 4" will be enough.

 

i have seen 43 pounds stacked with the eze on level one of the va.. level 4 on the eze... 1385 post turbo !!!!!!!!