cup pipe - primary delete question
Rennlist Member
Joined: May 2007
Posts: 3,071
Likes: 295
I just purchased the last primary bypass Maxspeed had in stock this afternoon. It ships Monday and I'll report on my impressions once installed. I am guessing a Sport Cat is next. This will finalize my exhaust upgrades for now. Nxt up...suspension.
Burning Brakes
Joined: Apr 2009
Posts: 877
Likes: 6
From: Tyler, Texas
I have my car at the shop for the primary bypass and cat bypass. I also read many old threads and the conclusion I made was very similar to what has been stated in the replies to this thread.
From what I read, this is what I concluded: primary delete is not too loud. Apparently, many claim the secondary delete will give you a louder note. The primary delete takes some weight off the very back, which will decrease your rear weight bias and polar moment, which should help handling. The primary delete adds mild HP gains and some claim that the secondary delete may actually decrease HP. Removing all is very loud and without much power gain.
My mechanic also says removing the primary and cat will eliminate some heat generation and improve air circulation, improving engine cooling. I hope this will help my cut airbox draw in less hot air. Even so, I am not expecting big HP gains, but I hope for better sound and hopefully a quicker revving more responsive engine.
From what I read, this is what I concluded: primary delete is not too loud. Apparently, many claim the secondary delete will give you a louder note. The primary delete takes some weight off the very back, which will decrease your rear weight bias and polar moment, which should help handling. The primary delete adds mild HP gains and some claim that the secondary delete may actually decrease HP. Removing all is very loud and without much power gain.
My mechanic also says removing the primary and cat will eliminate some heat generation and improve air circulation, improving engine cooling. I hope this will help my cut airbox draw in less hot air. Even so, I am not expecting big HP gains, but I hope for better sound and hopefully a quicker revving more responsive engine.
Drifting
Joined: Jul 2001
Posts: 2,298
Likes: 78
From: St. Louis
Since I have had a couple of people PM me about the pipe, here is the FS post on Pelican - http://forums.pelicanparts.com/showthread.php?p=4124428. I have some oil & air filters floating around as well. OEM and a K&N IIRC.
Burning Brakes
Joined: Apr 2003
Posts: 905
Likes: 2
From: Leeds, UK
I have a primary bypass (Cup pipe) and CAT bypass on my C4 and whilst I like the sound I preferred the sound of the secondary bypass (G-Pipe) on my old C2. There are lots of video clips on YouTube showing the differences in sound for you to do a comparison. I think any performance increases are minimal so if I was making the decision again I would go with the sound I prefer rather than anything else. As for the choice of manufacturer the biggest issue is generally with how well they fit. I went with a cheap cup pipe off the German ebay and there were no fitment issues but I went for a Dansk cat bypass and the fitment is not the best to be honest so I wouldn't assume that higher cost makes for a better piece.
