Adnan Siddiqui

Hello everyone,

I recently purchased NeedsWings downpipes for our C32s. I wasn't able to find the answer on the forum so I was wondering that will I have to get the car retuned once I install the downpipes or no?

insame1

you don't have to but you wont get the real gains until you do.

Lenin

What parameters would you tune for the downpipes?

insame1

I am not a tuner but I am assuming that the reason he went with down-pipes was to remove the cats. If that is the truth then he is moving more and would benefit from a tune.
it would probably be wise to upgrade the air intake before spending money on it though.

Adnan Siddiqui

As per Eurocharged I do not need a retune. Already have the air intakes.

insame1

Good to know.

Morphh

What downpipes ? For srt6 from needswing?
Didn't think they made downpipes for c32

Adnan Siddiqui

Rob has downpipes for our C32s, just not on his website, if you are interested email him. They look very much like SL32 ones... here is the link
http://www.needswings.com/needswings...lete-downpipes

kramykram

Hmmm i've always had the understand superchargers needed back pressure to get the full functionality out of them. That is why most people cut out the secondary cats. Am I missing something here??

Adnan Siddiqui

I honestly do not know the answer to your question. I usually ask Lenin(in the above comments) if I have any questions. He knows these cars inside out.

Lenin

For starters, in simple terms, the engine is an air pump. The more air you can pump through it in a set period of time, the more power you will make. That's why the saying "no replacement for displacement". With the downpipes and the removal of the cats you are obviously not changing the displacement, but you are making it easier for the pump (engine) to push the exhaust air out so that more air can come in quicker. The backpressure comment is often confused with the need to maintain an ideal scavenger effect. https://en.wikipedia.org/wiki/Scavenging_(automotive) "Modifying the exhaust system, (i.e. modifying the exhaust gas velocity by changing exhaust tube diameters) can detract from the "ideal" scavenging effects, and reduce fuel efficiency and power if not properly planned out and executed". I'm obviously not saying that Needswings downpipes create a more ideal scavenging effect. I just don't know. But Rob had reported that these downpipes with exhaust cutouts on the SLK32 made the car cut 0.2 sec from 1/4 mile ET and increased top speed by 2-3 MPH.

C3Duece

The best bang for the performance buck regarding exhaust mods for the c32 is the either completely remove or replace the front cats with high flow models. I had some 300 cell units installed and noticed a loss of low end power but a big improvement in mid range torque. Headers w/out doing the front cats is a waste of time/money.

I'll make up the low end loss with the 62mm pulley.