[truegret]

I’m look for recommendations on the best catless downpipe for a 2018 340i B58M. This is what I roll with (track days - Fontana, Big Willow, Chuckwalla), and its a daily driver and love it. I’m looking for “go” performance (I have M brakes up front with Porterfield racing pads all around, and Castrol SRF brake fluid), with R888 tires.

2018 340i B58M
JB4 tuner (love it)
100 octane

I typically run map 2. I’ve run map 5, but it goes to stupid mode when exiting a medium speed (60-80mph) turns.

Two questions:
Any recommendations for the best catless downpipe so that I can run map 5 (and whoop on my Porsche GT3 buddies - )?

I se 4” (VM) and 4.5” (VRSF) offerings ... what does my ‘18 340i require?

Thanks in advance!

[B58]

You can run either, but i have the vrsf 4.5" catless. It's decently priced cheap and fits great.

[truegret]

Hey thanks B58 .... much appreciated. Yea, the VRSF is a reasonable weight and price. They don’t offer anything newer than 2016 340i. I emailed them and am awaiting a response. I had the same challenge with Porterfield .... they had to design and make up pads for 2018.

Cheers

[BLACK HAWK DOWN]

Originally Posted by truegret

Hey thanks B58 .... much appreciated. Yea, the VRSF is a reasonable weight and price. They don't offer anything newer than 2016 340i. I emailed them and am awaiting a response. I had the same challenge with Porterfield .... they had to design and make up pads for 2018.

Cheers

And the difference between the DP made for a 2016 and one made for a 2018 are?

[eksigned]

All the same. You're just paying for quality really. +1 for ER though.

[estorilbluef36]

Originally Posted by truegret

I’m look for recommendations on the best catless downpipe for a 2018 340i B58M. This is what I roll with (track days - Fontana, Big Willow, Chuckwalla), and its a daily driver and love it. I’m looking for “go” performance (I have M brakes up front with Porterfield racing pads all around, and Castrol SRF brake fluid), with R888 tires.

2018 340i B58M
JB4 tuner (love it)
100 octane

I typically run map 2. I’ve run map 5, but it goes to stupid mode when exiting a medium speed (60-80mph) turns.

Two questions:
Any recommendations for the best catless downpipe so that I can run map 5 (and whoop on my Porsche GT3 buddies - )?

I se 4” (VM) and 4.5” (VRSF) offerings ... what does my ‘18 340i require?

Thanks in advance!

i have Evolution Racewerks. Best downpipe you can get for the B58

[flyknit]

Any feedback on ER catted dp? Am on akrapovic exos and thinking of pair it with ER catted dp.

[rahlow]

Originally Posted by flyknit

Any feedback on ER catted dp? Am on akrapovic exos and thinking of pair it with ER catted dp.

I think user B58 had the 5" catted downpipe but recently switched to the 4.5" catless like the most of us. Curious on his opinion there. I've always had the ER catless and it's been great.

[JD11937]

Originally Posted by flyknit

Any feedback on ER catted dp? Am on akrapovic exos and thinking of pair it with ER catted dp.

I can speak for the CG Precision catted downpipe, it's great. 5" cat for less restriction. It has thrown a code, will be installing an o2 extender to hopefully fix that.

[B58]

Originally Posted by truegret

Hey thanks B58 .... much appreciated. Yea, the VRSF is a reasonable weight and price. They don’t offer anything newer than 2016 340i. I emailed them and am awaiting a response. I had the same challenge with Porterfield .... they had to design and make up pads for 2018.

Cheers

I have a 2018 340i and the VRSF catless fit.

[B58]

Originally Posted by rahlow

I think user B58 had the 5" catted downpipe but recently switched to the 4.5" catless like the most of us. Curious on his opinion there. I've always had the ER catless and it's been great.

It made absolutely no difference going from the 5" CG catted to a 4.5" catless. Everything feels the same my car just smells like shit now, pops a little more, and spits flames out from meth exiting the exhaust when it gets really hot. Power wise and throttle response are the same. I'm running the 42Draft o2 spacer and its never thrown a check engine light. I only went catless because once BEF is out i want to switch to a pure stage 2 and get the best flow possible.

This is listed for VW/Audi, but it works on the BMW. I had this spacer on my 2016 GTI and took it off and kept it and now it's on my 340i: https://www.hstuning.com/42-draft-de...or-spacer.html

[F3085258]

B58, how bad is the smell? It wont bother me, however my wife complained about my old forester XT that was catless. Happy wife, happy life...

Also thinking of going to Pure stage 2 when BEF is out. How much of a compromise will a 5" catted be with Pure S2?

[jalkster]

Originally Posted by F3085258

B58, how bad is the smell? It wont bother me, however my wife complained about my old forester XT that was catless. Happy wife, happy life...

Also thinking of going to Pure stage 2 when BEF is out. How much of a compromise will a 5" catted be with Pure S2?

iMinLuv melted his 5" catted dp with ps1 and meth.

also, BEF is out. Are you referring to a specific MHD BEF?

[B58]

Originally Posted by F3085258

B58, how bad is the smell? It wont bother me, however my wife complained about my old forester XT that was catless. Happy wife, happy life...

Also thinking of going to Pure stage 2 when BEF is out. How much of a compromise will a 5" catted be with Pure S2?

It smells like shit man when you’re at a stop, but you get use to it haha. As stated above the cat can melt with meth and bigger turbo and more boost that’s another reason why I went catless.

[B58]

Originally Posted by jalkster

also, BEF is out. Are you referring to a specific MHD BEF?

This is exactly what we’re all waiting for..... great progress by Terry he said we’re going to love it once it’s done.

[F3085258]

My garage is attached to the house and I am sure it will stink up the garage when I start and even get in to the house. That wont play well with my wife.

I wonder if a universal 100 cell cat mounted where the resonator is would not melt?. They are around $100 on summit. I put a magnaflow on my 5.3L LS swapped Wrangler as it smelt pretty bad and that eliminated it.

[G.Newt]

Originally Posted by B58

This is exactly what we’re all waiting for..... great progress by Terry he said we’re going to love it once it’s done.

You'd pick JB4/MHD BEF combo over a Pure Stage 2 OTS tune that is being worked on in conjunction with Pure Turbos themselves?

[mike@x-ph.com]

We used to offer VM, im pretty sure the product has been discontinued

We now offer VRSF, Wagner, CG precision and Evolution Racewerks downpipes

[B58]

Originally Posted by G.Newt

You'd pick JB4/MHD BEF combo over a Pure Stage 2 OTS tune that is being worked on in conjunction with Pure Turbos themselves?

I'm not sure exactly, but time will tell once everything is released. If the B58 can consistently do 500whp on a stock turbo with meth + BEF then it might be satisfying enough to not even switch to a pure s2 turbo with a ots file.

[Msmith340xi]

Originally Posted by B58

It smells like shit man when you’re at a stop, but you get use to it haha. As stated above the cat can melt with meth and bigger turbo and more boost that’s another reason why I went catless.

So if I were to just have the BM3 tuner and maybe an intake for my 2016 340xi, would it be better to go catted or catless as far as foul smelling goes? Looking to daily drive it

[mike@x-ph.com]

Originally Posted by Msmith340xi

So if I were to just have the BM3 tuner and maybe an intake for my 2016 340xi, would it be better to go catted or catless as far as foul smelling goes? Looking to daily drive it

catless will always have a fuel smell

[Ifellapart]

Originally Posted by Msmith340xi

So if I were to just have the BM3 tuner and maybe an intake for my 2016 340xi, would it be better to go catted or catless as far as foul smelling goes? Looking to daily drive it

Do an "E" fuel mix and it'll smell like popcorn