Latest mod....

[primetime]

First mod of the winter.... Probably won't put them on for a few months.... Debated on getting the eurocode headers as they will produce better results but was worried a little about sound.... Was gonna wait and see some real world vids and results but then a very good deal came up on these..... so I took the cheap route and got these.... I am hoping they also don't throw a CEL, but will see.... Hopefully, I will get 10-30hp/tq and a tenth or two at the track..... Just getting started..... Thoughts?

[mbgt72]

So is this your little secret that UPS was delivering?

Are they catted, or just a chamber to look like cats. I thought the stock B8 header collection was catted and that you couldn't remove the DP's without a motor pull b/c of the size of the cat/resonator.


Anyhow I think we'll all be looking forward to your results and impressions on them. About time some new pipes were brought to the B8's!

[primetime]

So is this your little secret that UPS was delivering?

Are they catted, or just a chamber to look like cats. I thought the stock B8 header collection was catted and that you couldn't remove the DP's without a motor pull b/c of the size of the cat/resonator.


Anyhow I think we'll all be looking forward to your results and impressions on them. About time some new pipes were brought to the B8's!

Yeah that was my little secret.... Sorry for the letdown! lol I'm excited! Anyway, yes these are the 034 motorsports HFC that replace what I believe is called the catalytic pipe.... The B8's have 4 parts to their exhausts, a header pipe, catalytic pipe, downpipes, and catback.... APR has a nice diagram on their site.... The eurocode headers replace both the header and catalytic pipe and at this point is the only other option, I believe a member may be posting some pics of those soon.... Not 100% sure will have to pull the motor or what it will take, need to get the car back on a lift.... No hurry as the car won't be driven until late March early April anyway.... It will be ready for the track in early April

[richib86]

nah the cats bolt up between the "downpipe" and the manifolds. you dont have to pull the motor but you do have to drop and hang it a little just toe get the clearance to pull the cats out, the stockers are HUUUUUUUUGE

[richib86]

and monday to be exact... lol

[primetime]

nah the cats bolt up between the "downpipe" and the manifolds. you dont have to pull the motor but you do have to drop and hang it a little just toe get the clearance to pull the cats out, the stockers are HUUUUUUUUGE

That is what I have heard as well.... How bad of a job? Debating on doing it with my brother vs having it done....

How do you think these will perform?

and monday to be exact... lol

Nice... Is that the install date?

[beemercer]

ruh roh richi's getting headers?

[voltrons_head]

April is a long wait. You're more patient than I am PT. Can't wait til the spring.

Looking forward to get Richi's feedback on the headers as well.

Did we ever get feedback from Eurocode's 1/4 mile runs?

[primetime]

April is a long wait. You're more patient than I am PT. Can't wait til the spring.

Looking forward to get Richi's feedback on the headers as well.

Did we ever get feedback from Eurocode's 1/4 mile runs?

Kind of used to it from past experiences.... Gives me something to look forward to.... Yes, really looking forward to his results and the sound.... Since I am waiting I can always change my mind.... Haven't seen the results from eurocode, kind of bummed as I wanted to see how the car performed...

[voltrons_head]

Haven't seen the results from eurocode, kind of bummed as I wanted to see how the car performed...

I need to go find that thread cause I think it just disappeared without any results. Anyway the HFC's should sound proper with the Milltek.

[sakimano]

April is a long wait. You're more patient than I am PT. Can't wait til the spring.

Looking forward to get Richi's feedback on the headers as well.

Did we ever get feedback from Eurocode's 1/4 mile runs?

the 'hired gun' driver, Mike Hood, posts on here actually. He was saying that the night he was supposed to go, it was busting rain. Then he found there was trouble with the stock clutch. Then the whole topic died on the vine.

maybe he ran 13.0

just kidding...hopefully he'll chime in.

[richib86]

well until the track is open again, pulls it is lol

[voltrons_head]

well until the track is open again, pulls it is lol

Make sure that GoPro is running.....!

[sakimano]

yeah, the B8 exhaust is a jumbled mess

4 parts
can't remove DPs without pulling engine
monster cats

It's a really weird setup.

I've asked a few folks what the catback/dp/midpipe/whatever the bits are all called diameter is but can never seem to get a straight answer. Not sure what AWE/STASIS/APR/MILLTEK are doing with their setups? If I was a betting man, the FI setup will be optimized for performance. but again, never seemed to get a straight answer. Maybe I missed the discussion?

[voltrons_head]

but again, never seemed to get a straight answer. Maybe I missed the discussion?

Awe advertises their setup as 2.5" but that only accounts for their "midpipes" and back.

[richib86]

the catback and "downpipes" are all 2.5 on my setup, stock is 2 1/4

[beemercer]

cats out, the stockers are HUUUUUUUUGE

Keep in mind a large cat is not a bad thing. A large diameter catalyst chamber will help diminish pressure drop through the cat by providing more open area to flow. Though a longer length will increase pressure drop. So you can achieve the desired conversion by either designing a long or a wide cat, clearly a wide cat is the better choice.

[JEmm]

Did eurocode ever even post up vids of the setup? Wanted to hear it but never saw a video for it...

[primetime]

Keep in mind a large cat is not a bad thing. A large diameter catalyst chamber will help diminish pressure drop through the cat by providing more open area to flow. Though a longer length will increase pressure drop. So you can achieve the desired conversion by either designing a long or a wide cat, clearly a wide cat is the better choice.

Would you mind expanding upon this? Is this a function of volumetric efficeincy? On every car that I have replaced factory cats with aftermarket HFC's I picked up power.... Do you feel that won't be the case here? If so why not.....

[voltrons_head]

I think beem is just offering input as to why the OEM design is so fat not that you wont see improvement.

[sakimano]

isnt' the OEM 'cat' also a resonator of some sort? I saw that posted somewhere, so it could be complete bunk. i.e. there's more going on in that big chamber than just catalytic conversion

[richib86]

isnt' the OEM 'cat' also a resonator of some sort? I saw that posted somewhere, so it could be complete bunk. i.e. there's more going on in that big chamber than just catalytic conversion

its actualy a Helmholtz resonance chamber with cats built into it, one of the reasons a hair dryer is louder than a stock s4

[NWS4Guy]

its actualy a Helmholtz resonance chamber with cats built into it, one of the reasons a hair dryer is louder than a stock s4

Exactly. Also, you can pull the downpipes without touching the engine, I know Sak likely was referring to the Cats, since they are integrated with the DP's on other models, but here they are a seperate piece.

[beemercer]

Would you mind expanding upon this? Is this a function of volumetric efficeincy? On every car that I have replaced factory cats with aftermarket HFC's I picked up power.... Do you feel that won't be the case here? If so why not.....

Well consider that the chamber has a total empty volume of V
And the catalyst matrix occupies some volume C
Then there is an open area to flow F

Now depeding on how tightly packed the catalyst matrix is you have a specific void fraction, let's say x, that basically tells you what portion of the total empty volume is left open.

So basically x*V=F and V-F=C.

So if you increase the total volume of chamber at a constant void fraction you have more volume open to flow. Or, you can increase the void fraction for the catalyst.. basically a less dense matrix. Either way will increase the volume open to flow.

Now a less dense matrix is akin to a sport catalyst which has a lower cell count. So your high flow cats may be smaller diameter, but they have a less dense catalyst packing which leaves a greater fraction of the cross sectional area open to flow. So, though they may be smaller, they have more open area so they should flow more.