[bradsm87]

I just saw pics and realised that the N55 turbo has its turbine housing mounted via a bracket to the engine! That would give it plenty enough support. Now I'm thinking I'll just get the VRSF DP. It has a flex section but no mounts.

Thoughts?

[N55shack]

Has anyone heard if it's safe to just clear the stock cat out and basically make it catless? Or is this a no go?

[InHousePerformance]

Originally Posted by N55shack

Has anyone heard if it's safe to just clear the stock cat out and basically make it catless? Or is this a no go?

Did you read the first page of this thread? Thats all they talk about....

[John H.]

Originally Posted by N55shack

Has anyone heard if it's safe to just clear the stock cat out and basically make it catless? Or is this a no go?

Gutting the cat is fairly easy. Performance arguments go both ways; however, I've never had any problems gutting cats. OEM cats are hard to beat for fitment. Pictured below is a gutted OEM cat. Also, I had it polished....of course, it will change color in due use. I still have my original cat on the car. I bought the cat on eBay, and gutted it.

I am hesitant to install it, as the local police are subjectively ticketing vehicles that look and sound loud. It's a pita, and they already eye my car because I'm lowered, and my mufflers are polished.

[N55shack]

Originally Posted by Bullitts5

Did you read the first page of this thread? Thats all they talk about....

Yes I have but no one has mentioned if it was safe or not, preciate the feedback👍🏼

[N55shack]

Originally Posted by John H.

Gutting the cat is fairly easy. Performance arguments go both ways; however, I've never had any problems gutting cats. OEM cats are hard to beat for fitment. Pictured below is a gutted OEM cat. Also, I had it polished....of course, it will change color in due use. I still have my original cat on the car. I bought the cat on eBay, and gutted it.

I am hesitant to install it, as the local police are subjectively ticketing vehicles that look and sound loud. It's a pita, and they already eye my car because I'm lowered, and my mufflers are polished.

Yeah I've done it on pretty much all the cars I've ever owned to be honest. Just wondering if it's going to cause any issues in the long run because of the turbo and the big pocket where exhaust can get caught up in. I appreciate all the info and pic, means a lot!

[N55shack]

Originally Posted by John H.

Gutting the cat is fairly easy. Performance arguments go both ways; however, I've never had any problems gutting cats. OEM cats are hard to beat for fitment. Pictured below is a gutted OEM cat. Also, I had it polished....of course, it will change color in due use. I still have my original cat on the car. I bought the cat on eBay, and gutted it.

I am hesitant to install it, as the local police are subjectively ticketing vehicles that look and sound loud. It's a pita, and they already eye my car because I'm lowered, and my mufflers are polished.

Also, I'm new to this page, how would I make a new post?

[WaqasRiyami]

As a finished project imho - evolutionracewerks Competition Series 4" Catless Downpipe 535i/640i N55 Engine

[etnsandman]

I purchased a low mileage OEM catted downpipe off here and then gutted my 100k Mile one. So I can go back to factory if needed. As for smell, its nothing. The wife did notice at first. She is used to it now. Smells fine on E30.

[lsturbointeg]

I'm gonna ask as I've never seen it done but how exactly do you guys gut the DP and does the exhaust note change at all? Thanks!

[InHousePerformance]

Originally Posted by lsturbointeg

I'm gonna ask as I've never seen it done but how exactly do you guys gut the DP and does the exhaust note change at all? Thanks!

Some people actually cut them in half and clear out the honeycomb as best they can with chisels and other tools and then weld them back together. Ive seen others use punches, torches and bunch of other crafty tools to remove the internals without cutting it apart. Personally I would cut and weld and get out as much of the internals as possible but to each their own.

[bradsm87]

It's completely unnecessary to cut and weld. Just use a long spade bit and a drill and it cuts through the honeycomb like butter.


Having said that, gutted cats are crap. The big empty chamber is shit for both sound and turbulence.

[T-Bone18]

Can somebody make a video of what our F10 N55 sound like with a gutted DP vs VRSF Catless downpipe video vs Highflow downpipe, all these with stock exhaust.

[Unspec]

Originally Posted by T-Bone18

Can somebody make a video of what our F10 N55 sound like with a gutted DP vs VRSF Catless downpipe video vs Highflow downpipe, all these with stock exhaust.

That's a fuck ton of work to basically get "sounds like nothing, sounds like nothing, sounds like nothing". The stock mufflers are really good at muffling.

[5soko]

Originally Posted by T-Bone18

Can somebody make a video of what our F10 N55 sound like with a gutted DP vs VRSF Catless downpipe video vs Highflow downpipe, all these with stock exhaust.

They are both pretty quiet, i cant tell the difference between the two honestly.

[T-Bone18]

Originally Posted by 5soko

They are both pretty quiet, i cant tell the difference between the two honestly.

That sounds amazing for now.
Now my next dilemma is, how bad is the smell and how do you guys deal with that ?
Again we driving a 5 series, which is mostly for comfort. I don't know if you guys carry people in the back seat, your kids maybe, so how it is in the cabin odor wise ? Also, does it smoke ?

Evolution Racewerks have a Ceramic Coating DP and here is what they advertise. I would like to know what is your opinion on that feature regarding the smell ? Do you think it's actually smoke less with less fume, less odor or no difference ?

Ceramic Thermal Coating
The purpose of ceramic coating downpipes is to keep heat from the exhaust gases inside the downpipe from radiating out. This keeps underhood temperatures lower and less heat absorption by nearby parts/surfaces. Another added benefit is that by keeping in heat (energy) in the exhaust gases inside the downpipe, exhaust flow velocities stay up, resulting in lower backpressure.

[Unspec]

Originally Posted by T-Bone18

That sounds amazing for now.
Now my next dilemma is, how bad is the smell and how do you guys deal with that ?
Again we driving a 5 series, which is mostly for comfort. I don't know if you guys carry people in the back seat, your kids maybe, so how it is in the cabin odor wise ? Also, does it smoke ?

Evolution Racewerks have a Ceramic Coating DP and here is what they advertise. I would like to know what is your opinion on that feature regarding the smell ? Do you think it's actually smoke less with less fume, less odor or no difference ?

Ceramic Thermal Coating
The purpose of ceramic coating downpipes is to keep heat from the exhaust gases inside the downpipe from radiating out. This keeps underhood temperatures lower and less heat absorption by nearby parts/surfaces. Another added benefit is that by keeping in heat (energy) in the exhaust gases inside the downpipe, exhaust flow velocities stay up, resulting in lower backpressure.

The thermal coating is honestly for looks. The cat goes immediately into non-coated exhaust piping, so it's a negligible difference.

Even with my hi-flow cats, you can get a strong smell of gas when you're behind the car. So imagine that, but in your cabin, at every stop light. It won't smoke though. If you're comfort oriented, just go for a high flow one and be done with it.

[lsturbointeg]

i've had mine on for quite awhile now and as long as it's installed correctly with no leaks i do not smell anything in the car. now if i'm sitting at a light and the wind is blowing over me than yes i can smell the gas. but even than it doesn't bother me at all. if you're going to be around a bunch of modified cars with everyone revving how are you not gonna smell the exhaust that's being put into the air...it just gives me the sense of it's GO TIME!!!

[T-Bone18]

I will start with BM3 Stage2 + IC + CP for a while and do the cat mod later. Will see.
Thx for info. I was more concern into the cabin, outside I don't care.