I recently purchased the Stillen V3 Supercharger and was advised by them that I would have to remove my Motordyne ART pipes. I am a bit grieved by this and asked why. I was told by the rep that the SC needs a certain amount of back pressure to achieve the full PSI boost levels. I have done some searching and can't come up with any supporting evidence for their claim. On a 370Z forum one poster suggested that it was just with the Stillen tune that the pipes would not work. I do plan on a custom tune as I consider the Stillen one to be a base map. Would it hurt anything if I left my ART pipes on?I would hate to have to go back to stock cats... any advice greatly appreciated.

 

There's a sticky thread around here on backpressure... I'd look at that first. Especially in a forced induction setup you want as little restriction as possible in the exhaust, so I think they're feeding you a line of BS. Unless, they are trying to sell you a "50-state legal" kit, in which case you'd need the cats to technically be "legal". If that is the case they should be telling you the real reason up front...

If the supercharger cannot reach it's full boost pressure without the aid of a clogged-up exhaust, you've got some major design flaws with the kit/install.

 

Herostar... thanks for your reply, I will search out the backpressure post. You raise a good point on the Stillen clan wanting to be CARB legal. This of course does not apply in Canada... so I would be disappointed if they are forcing this on me. They did say that they would modify their base tune to accommodate my Invidia exhaust, but insisted that I needed to go back to stock cats. Even high flow cats were unacceptable and my test pipes were definitely not. I do agree that for forced induction with turbo you want as little back pressure as possible... I just don't know if that is true for a SC application. I will do some more digging and post what I find.

 

I had HFC's and removed them and went back to stock cats as well with my Stillen SC. A few members had stock cats made great power and when he switched to ART pipes he made less after the re-tune so then he went back to stock cats to gain back that lost power.

 

Thanks... much appreciated! Now I just need to understand why.

 

I made the most power with OEM cats. Yes I had ART pipes for a brief amount of time.

 

Thanks guys... I guess I have my answer. Anyone need ART pipes?

 

I had TP with my stillen kit. Then changed back to stock CATs. Found better low end power and overall sounded way better actually.

 

Thanks for this... I was a bit concerned that it would really change the sound and not in a good way.

 

Can anyone explain this to me in a technical way? I'm having trouble understanding how reducing flow will increase power...

 

Did I also read in a Stillen thread that HFCs tend to burn out in less than a year? The stock cats seem to work best IIRC.

 

More back pressure is how the setup was designed. The more back pressure the faster the spool, and the more consistent power. Having more airflow is great, but it will essentially give you less of a power band

 

^^ That makes zero sense to me. Spool response should benefit from REDUCED back-pressure. I sense the ECU isn't properly mapped when I see someone saying back pressure is good. More back-pressure just means you're running closer to surge, and surge is bad.

 

Dont forget its a supercharger not a turbo.

 

And I don't see how that makes a difference. Roots, centrifugal, whatever, they shouldn't need back-pressure. Only reason I can see is the fuel map can't handle the potential flow so back-pressure is used to limit intake flow. Or it's a crazy way to create EGR-like conditions?

Please, someone explain this or point me to an explanation. I've been a car guy since the Eighties and this is new to me.