Stock Down pipe is 2 5/8"?

Mwilbur516 · Dec 8, 2011

I was under the impression that the stock DP was 3.25". When I got mine off (I had to cut it just below the firewall to get it out) this is what I found. With this tiny DP and the fact that scoop for the EGR cooler takes up 65% of the passenger side up pipe its no wonder my EGT's were up around 1650* on a hard run. Tomorrow I'll be installing the up pipe without the scoop and the EGR cooler hole welded shut and my new MBRP exhaust. Wonder how much the temps will drop and if the turbo will spool quicker. The pics show the difference between the MBRP (left) and the POS stock (right).

Triple H · Dec 11, 2011

Is it the picture or is the stock DP all squarshed up??

I see you have an '06 but I have not experienced a foil wrapped pipe. Can't remember what my Dads '06 looked like but I don't remember anything like that laying around in the bone pile.

My '04 was 3" and none of that foil garbage, nor were did our up-pipes have scoops :thumbsup:

Anyways enjoy you're new parts. No doubts there on what will directing your exhaust around now :redspotdance:

Triple H · Dec 11, 2011

Now after posting I can't make up my mind what my stock pipe measured at. I'll have to call up the old man to have him dig through the bone pile to assure myself now lol

genuineford · Dec 11, 2011

Triple H said:
Is it the picture or is the stock DP all squarshed up??

I see you have an '06 but I have not experienced a foil wrapped pipe. Can't remember what my Dads '06 looked like but I don't remember anything like that laying around in the bone pile.

My '04 was 3" and none of that foil garbage, nor were did our up-pipes have scoops :thumbsup:

Anyways enjoy you're new parts. No doubts there on what will directing your exhaust around now :redspotdance:

Our 03 had the foil wrap on it.

Mwilbur516 · Dec 11, 2011

Thats the stock DP off my 06' . Thats a sh*tload of foil around it and it isn't squashed up. I still have the pieces if anyone wants another picture. I have already notice significant drops in EGT's. I was really surprised when I saw it too, but thats the way it came from the factory. Between the small DP, the resonator and the stock exhaust size, it's really no wonder my EGT's were runnin' so high.

lubeowner · Dec 11, 2011

Mwilbur516 said:
Thats the stock DP off my 06' . Thats a sh*tload of foil around it and it isn't squashed up. I still have the pieces if anyone wants another picture. I have already notice significant drops in EGT's. I was really surprised when I saw it too, but thats the way it came from the factory. Between the small DP, the resonator and the stock exhaust size, it's really no wonder my EGT's were runnin' so high.

Did you buy your truck used?

Mwilbur516 · Dec 11, 2011

lubeowner said:
Did you buy your truck used?

Yeah why? The oasis showed only a new turbo at 41,000 miles. I got my truck with 41,500.

lubeowner · Dec 11, 2011

That is a 2003 downpipe.

Mwilbur516 · Dec 11, 2011

Were they changed in the later years? The truck had the Cat and muffler still in place. Any clue why that DP would be on it?

lubeowner · Dec 11, 2011

Just the 03 have the foil. Why its on there, who knows, but that is not a 06 downpipe. Maybe the previous owner had an aftermarket exhaust on that truck. Then before he traded the truck in he swapped the exhaust with a 2003 truck.

strokin6L · Dec 11, 2011

I know my '04 had the foil wrapped around the downpipe.

Mwilbur516 · Dec 11, 2011

lubeowner said:
Just the 03 have the foil. Why its on there, who knows, but that is not a 06 downpipe. Maybe the previous owner had an aftermarket exhaust on that truck. Then before he traded the truck in he swapped the exhaust with a 2003 truck.

Huh, Oh well its gone now and the new MBRP exhaust is great. Why did the 03's have foil and were the 04-07's any bigger? Wouldn't you have to pull the cab to install the DP as one piece? I don't see how you could get that DP out without cutting it, so it only makes since that it wouldn't go in without cutting.

lubeowner · Dec 11, 2011

strokin6L said:
I know my '04 had the foil wrapped around the downpipe.

On the early built 04 yes.

Mwilbur516 · Dec 11, 2011

So did the DP's get any larger after the foil was removed in early 04'. 2 5/8 is tiny for the flow these engines produce. I know my truck boosts less on some tunes (25psi), but on the Looney Wild it hits 35psi. It gets up to around 33psi on the stock tune, but theres not as much fuel so its not as hot. I do know that 03-07' all had 3.5" exhaust systems, at least after the DP.

SIX_OHH · Dec 11, 2011

do you have a track time? I think my dp opening is 3.5 inches

lubeowner · Dec 11, 2011

Mwilbur516 said:
Huh, Oh well its gone now and the new MBRP exhaust is great. Why did the 03's have foil and were the 04-07's any bigger? Wouldn't you have to pull the cab to install the DP as one piece? I don't see how you could get that DP out without cutting it, so it only makes since that it wouldn't go in without cutting.

Drop the Tranny cross member. Only takes a minute when on the lift. The early turbos were loud. The resonator was put on them to quiet the 03 wistle. The foil was added for heat and sound.

Mwilbur516 · Dec 11, 2011

SIX_OHH said:
do you have a track time? I think my dp opening is 3.5 inches

The stock DP's I thought were 3". My MBRP DP is 3.5" I.D. What are talking about track times?

SIX_OHH · Dec 11, 2011

track times are obtained from a motor sports park with a drag strip.

Mwilbur516 · Dec 11, 2011

SIX_OHH said:
do you have a track time? I think my dp opening is 3.5 inches

BTW, it's your up pipe thats on my truck right now. No scoop and no EGR make a big difference. I plan on deleting the entire cooler this spring when I pull the turbo and intake for cleaning. I'm currently trying to negotiate with the wife to let me build a shop for working on the vehicles and so I can move my tools and work benches outta the garage.