[Mr. 5]

Downpipes are Downpipes..Right?

I always wondered if 3” DPs gained more power than the 2.5”, so I got my hands on a set and set up a personal dyno day. The DPs that I chose were the new Macht Schnell 3” DPs. When I told people what I was doing, most were curious with what the outcome would be, but they were hesitant. Some thought there would be no gain. Others said that if there was a gain then it would be very minimal.

So this was the plan…Since I already had the UR 2.5” downpipes on then I could just go to MD Automotive in the morning and dyno my car. I guess I could have used a dyno from another day but I wanted this test to be as accurate as possible.
After dynoing the car, I lifted the car up and replaced the 2.5” DPs with the Macht Schnell 3” DPs. I then drove the car around the block to make sure that everything was “adapted” if that makes sense. I put the car back on the dyno and then did more runs.

The only thing that got me hesitant was that in the morning at 9:00 am, the temps were nice and cool and then it heated up pretty well by 12:30 when I dyno’d again. So, the 2.5” DPs already had a little advantage.

The results? I was blown away! I can’t believe that I gained up to 15 whp and 15 wtq throughout the entire RPM band. It put me into a completely different league and it made me wonder about all of the comparisons that people do. Some people do some runs and they say that they have the same mods. “He has UR DPs and I have AR DPs, so we have the same mods.” This assumption of these 2 DPs being equal shouldn’t be made anymore.

Macht Schnell Downpipes

Let’s talk about the Macht Schnell DPs. I found out that they were coming out with the DPs and knowing me, I really like to try out new things. Somebody needs to do an independent review right? The DPs were put together very nicely. The welds are very professional and they were as close to full 3” as they could get. They are 3” the entire way until the very end at the flange.
Of course, they could be nice and shiny with cherries on top but if they don’t fit then there’s a problem. Not only did they fit but they fit even with about an 1/8th inch of wrap all over them. The install went extremely well and was done in about 3.5 hours. Another reason why I went with the Macht Schnell pipes is that they all come with a thermocouple bung for EGT gauges. If you don’t want to install an EGT gauge then you can just plug it up with no issues.

So now for the important part. Dynos!
They speak for themselves. I put a curser on some of the graphs so you can see the increases. Notice how boost went down while power went up.

Here are my mods:

GIAC Stage 1
OEM air box with scoops and aftermarket filter
Autobahn Exotics Exhaust (with High Flow Cats)
Active Autowerke IC

This is the order:

Graph 1 UR DPs
Graph 2 Macht Schnell DPs
Graph 3 The best run of Macht Schnell with the best of UR (3.5k curser)
Graph 4 The best run of Macht Schnell with the best of UR (6.5k curser)
Graph 5 The worst run of Macht Schnell with the worst of UR (3.5k curser)
Graph 6 The worst run of Macht Schnell with the worst of UR (6.5k curser)

Enjoy!

Pictures of the Macht Schnell DPs are on the end. (Wrapped and before the were wrapped)

[JayKay335i]

What? VK group buy members rolling over in their chinese bubble wrap?

Nice gains.

[ridin135]

Originally Posted by JayKay335i

What? VK group buy members rolling over in their chinese bubble wrap?

Nice gains.

7 hp difference doesn't bother me one bit I am still glad I got my vk downpipes. Gald someone did this by the way

[e.n335]

So average gain is ~ 7 whp / 7 wtq ?

[Mr. 5]

Originally Posted by JayKay335i

What? VK group buy members rolling over in their chinese bubble wrap?

Nice gains.

Please refrain from making comments like that.
I don't want this thread to turn into anything of the sort.
This thread should invite technical discussions.

[ar design]

Great info Mr. 5!

[Snertz]

Awesome info, thanks!

Nice looking DP's, are they available to the public yet and for how much?

[sd390r]

knew it

[Vince@ V K Motorwerks]

Nice dyno's Mr. 5. Congrads your car seems to be making some good power.

[Craig@SupremePower]

+1... Nice job Craig!

Originally Posted by ar design

Great info Mr. 5!

[pdjafari]

where are the guys who said 3" is too big and you'll lose power???

[e.n335]

Originally Posted by pdjafari

where are the guys who said 3" is too big and you'll lose power???

Why should you loose power by reducing backpressure on a turbo car ?

[jpsimon]

thanks for this comparison 5!

[jpsimon]

Originally Posted by pdjafari

where are the guys who said 3" is too big and you'll lose power???

the guy's who said that were talking about full 3" dual exhaust, not just the downpipes

[badass1g]

do you have any comparison from stock dp's to the UR's?

[ZTUNER]

Another datapoint from a different twin turbo car. At the 500 whp level we gained 28 whp going from a full 2.5 inch dual turbo back to a 3 inch dual turbo back. I see no reason for the 335 to be different. All the "restriction / backpressure" turbo engines is provided by the tiny opening in the throat of the exhaust housing. Bigger is truly better when it comes to turbo exhausts.

Harry

[R1000K3]

Great information Mr. 5, as ususal !

[klipseracer]

Where is my 4" dump tube at?

[TMR]

Looks awesome... Cant wait to get my AR DP's.

[john boxter]

thats a great comparison! the difference between 2.5 to 3.0 is almost the same as catted to catless!

[Terrance28]

Thats why when I finally decide to get dps it is gonna be AR dps.

[maui86]

you notice a difference with the heat wraps?