330-style Exhaust onto 328Ci (switch from "single" to "True dual")

I know something similar was asked recently, but my question is slightly different. I have a 328Ci, which as we all know, is a 2-1-2 exhaust. Now, I don't like having two tips but only being a "single pipe" system. I can't imagine it takes advantage of potential "flow" capabilities, so I want to go with a true-dual exhaust from the headers-back.

Would it be as simple as buying a 330Ci exhaust (rather, an aftermarket exhaust designed for the 330Ci), cutting off the flanges that connect the exhaust to the headers, and re-welding them to the proper angle? I can have the labor done for little to no money, so it's not an issue.

What I want to know is:
Will there be any noticeable benefit doing this as opposed to just getting a full-exhaust designed for a 328Ci? I will be supercharging the car (ESS TSx), so I would think the extra flow would help the car N/A AND FI. Is this the case?
Will this improve the sound over a comparable aftermarket 328 exhaust, or will it sound worse? I imagine it would be a bit louder, but not terribly. "Volume" isn't at the top of my worries at all.
I'm going to be installing eBay headers soon. Should I get the 328 Headers and just figure out how to bolt on a 330 exhaust, so that the only "flanges" I'm messing with are on the easier-to-access part of the headers (the exhaust's flanges to mate the headers, not the header's to mate the exhaust's)?

Thanks!

I imagine it could be done but don't imagine you will really gain any noticeable performance (aside from the ebay headers)

as one wise fanatic once said, anything can be done with enough cash

When I upgraded my exhaust, I went with a 330 exhaust (Supersprint didn't make a race 328 muffler). It is a true dual exhaust. Labor was minimal (less than $100) to modify the muffler to fit. Everything else pretty much bolted up just fine.

yeah bernstem hes not talkin about just a muffler hes talkin straight from the headers..its a little different and yours isnt a true dual exhaust since you just replaced the muffler

Originally Posted by zeppelin4

yeah bernstem hes not talkin about just a muffler hes talkin straight from the headers..its a little different and yours isnt a true dual exhaust since you just replaced the muffler

Well, I'm not talking about just a muffler either. I do know what a dual exhaust system is and the difference between a cat back and full exhaust. when I installed my supercharger and swapped out my cams and head, I also upgraded my exhaust. I went with Supersprint headers, cats and muffler. I had my shop make a set of custom mid-pipes.

Like Activ3 said, the easiest way is to buy 330 headers and the rest of the exhaust for a 330. When I upgraded, I just called Bimmerworld, told them what year my car was and what I wanted to do. They set everything up and shipped it directly to my shop. They sent me 330 exhaust headers, cats and muffler. All the parts bolted up fine with the exception of the muffler which needed custom brackets and Bimmerworld told me that up front.

As for HP gains, with a supercharger replacing the headers and exhaust will definitely give some power. Of the exhaust components, the headers are the most restrictive so replacing them will will give you the most gain. How much will depend on the rest of your engine and what other supporting modifications you have made.

Here are some pics of the install in case you thought I was just blowing smoke.

Enjoy.

sorry to hijack, but i just have a quick question (searched but had no luck..):

i have a 328Ci and i'm about to put some ebay headers on it. how much hp would the new headers alone with the stock 328 exhaust add? also, say i were to get 330 headers and a 330 dual exhaust, how much hp would that add?

I don't know that anyone can give you exact numbers, but you might get 5 -15hp (as a rough estimate) from headers. A lot depends on what else you have done to your engine. I don't think you will see any significant difference between a 328 and a 330 exhaust system unless you are pushing huge horsepower numbers (more then you are going to get with a N/A engine).

Keep in mind that the stock catalytic converters are in the headers so if you don't add aftermarket cats you will throw a CEL and won't be able to pass emissions.

Lastly, If you take the time to do a search you can find everything you want to know about headers.

Originally Posted by ventura_328Ci

sorry to hijack, but i just have a quick question (searched but had no luck..):

i have a 328Ci and i'm about to put some ebay headers on it. how much hp would the new headers alone with the stock 328 exhaust add? also, say i were to get 330 headers and a 330 dual exhaust, how much hp would that add?

yes, there was one person who had a DP made that allows a person to run a 330 exhaust on their 323/328. he put it up for sale about a year ago. let me try and find the thread.

http://forum.e46fanatics.com/showthr...light=downpipe

^there is the link.

Just buy the headers for a 330 and the stock dual 330 exhaust will bolt right up.