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e34nyc540i

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Discussion starter · #1 · (Edited)
Ok with the shocks replaced on the car (Koni adjustable sports) I thought I was done spending money as the plan was to get the best usage vs invested dollar out of this car. That said...maybe a little fun wouldn't hurt as I keep missing the sub 50mph cruising of my 68 Mustang v8. I know its too different era but while the cruising is great in this car the sound is sleepy....literally. My soon to be fiance falls asleep on almost every road trip.

Question:
Besides for legal emissions reasons does my e34 540i need the cats? As in will I get error codes if they are gone? I dont know where the o2 sensor is so apologies for the novice question.

My plan

Image

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- cut everything past the head off
- 2 to 1 pipe
- glasspack/cherrybomb
- then qtp wireless 2.5in cutout
- dynomax vt single exhaust one way (has no drone valve) nothing the other
- tips meet up to look stock

I realize I will get zero performance gains but after riding stupid fast motorcycles and super slow classics that performance in the real world is perception. If you are having fun and enjoying the experience who cares.

Here is what it would sound like on the GP side

Here is two Dynomax VTs on my old car with a 302 with H pipe

They muffle considerably almost to the point of being boring which is what I want on the quiet side.

Will I use the QP side often or ever in a public or residential area...NO.

Will I love carving up backroads in the country and occasionally surprising someone...HELL YEAH!

So let's hear it! Let me have it! What do you think about having push button quiet or roar?


Cost Guesstimate
QTP $300
Dynomax VT $130
Cherrybomb $50
Custom fab and tip $300ish
 
Leave the stock resonators but go ahead and cut the cats out. You want the resonators so you dont have that annoying drone inside the car. Also try just chopping off the muffler after the resonators and running straight pipes from there, it might be the sound your looking for.
 
Discussion starter · #3 ·
Leave the stock resonators but go ahead and cut the cats out. You want the resonators so you dont have that annoying drone inside the car. Also try just chopping off the muffler after the resonators and running straight pipes from there, it might be the sound your looking for.
The VTs have a valve to prevent drone when cruising. The whole point of my project is to keep it quiet and add a "sports loud" option.

The vids Ive seen with resonators and cats are too loud for normal cruising.
 
Awesome idea, not too crazy, but I'm planning on going just with loud :supdude: .... Not straight pipes loud, legal loud, but still no quiet. I'm a youngin, I don't need quiet. :thumbup:
 
I love it, I do. :angel: But, I'm only 16, so I live with my parents and if I stay out late, then roll in with pipes like that, it WILL wake me papa and he won't be happy. :bawling:
 
Discussion starter · #8 ·
I love it, I do. :angel: But, I'm only 16, so I live with my parents and if I stay out late, then roll in with pipes like that, it WILL wake me papa and he won't be happy. :bawling:
Hahaha....Im 32 and if I roll back into NYC sounding like that I will have some issues with police but the girlfriend long before even they show up.

I really think the remote valve is the way to go to have it all.
 
Im doing 2.5 duals from the cat all the way out with two 16.5 glass packs, right now my exhaust has rusted out, and separated after one cat, some one side is running straight from the cat, and i love the sound, slightly muffled since one side is still connected. No exhaust shop near me will touch my car, i have 100$ into all the parts i need minus the hangars, i already had some of those around.
 
Discussion starter · #14 ·
Any advice on pipe size guys?

I think the stock is 2in from the headers back but we are essentially going 2 to 1 so do I go 2.5 or 3in going out?

2 header pipes -> cherry bomb vortex (y inside) -> 2.25? 2.5?
 
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