[ConradConrad]

Anyone here with a DP without tune?

I'm pushing 80k and dont want to tune(been there done that-over it) the car as I will continue driving it. I wouldn't mind putting some money towards downpipes if what I read on here is true

1) General consensus is that there will be a mild change in the exhaust note
2) There will be a small power bump on stock boost
3) There will be a relief of backpressure from the turbos so they will:
a)spool a little more easily/quickly
b)provide a small step towards reliability.

Hence the $$$ towards a downpipes is justified if the above is true.

Any input?

[135Pats]

You won't see power gains. Sound will be altered a bit. It'll smell and potentially smoke. It reduces backpressure and evacuates exhaust gas more quickly, in that sense you are helping the turbos to breathe.

[Sason83]

Yeah DP with no tune = no point. Your better off just keeping the stock DPs on and saving yourself money/time.

[AS4EX]

Been there done that then you would understand a tune and dp's usually go hand and hand.

[ajsalida]

+1 on what others said but also you'll need a tune or DP fix to not have CEL's.

[SanquintinB]

Lets say you don't want to tune your car, you don't want the power gains and extra boost to stress your engine. Say you just want the sound that catless DPs produces. Would it be harmful in any way to NOT tune the car when you install DP's?

[135Pats]

Originally Posted by SanquintinB

Lets say you don't want to tune your car, you don't want the power gains and extra boost to stress your engine. Say you just want the sound that catless DPs produces. Would it be harmful in any way to NOT tune the car when you install DP's?

It's not harmful...I'm just really not seeing the point. The change in tone is relatively subtle, if more noise is what you want that's not an efficient way to do it.

You'll also have a constant CEL on the dash. But no, the car will drive just fine.

[Miller335]

Originally Posted by SanquintinB

Lets say you don't want to tune your car, you don't want the power gains and extra boost to stress your engine. Say you just want the sound that catless DPs produces. Would it be harmful in any way to NOT tune the car when you install DP's?

I'd rather find ways to get the tone you want after the cats/O2's then deal with all the cons that DP's bring without the main benefits.

[ConradConrad]

Originally Posted by SanquintinB

Would it be harmful in any way to NOT tune the car when you install DP's?

Fair question.

Still dont see how a catless dp won't spool turbos quicker even in a stock setting

[Jeff@TopGearSolutions]

Originally Posted by ConradConrad

Fair question.

Still dont see how a catless dp won't spool turbos quicker even in a stock setting

In theory they might but the minuscule lag already with stock boost would likely leave results close to negligible.

If you have no other mods I would consider an FMIC though, you might actually feel the gains on that considering even the stock intercooler on stock boost is inefficient, especially after some heat soak.

But if a little exhaust note is your goal then downpipes would be the way to go. A tune is fairly harmless on this car though. There are guys pushing in excess of 600WHP so surely a mild tune of 350WHP is really nothing to call home about in terms of pushing the engine out of it's "safe zone".

[SanquintinB]

Thanks for the quick replies fellas.

[BAL278]

if you just want a change in exhaust tone, do an ACM exhaust mod

[ConradConrad]

Originally Posted by BAL278

if you just want a change in exhaust tone, do an ACM exhaust mod

^^ isnt that an M3 thing?

How can anyone be "over it" when it comes to a tune? I just don't get it.

[V8bait]

Downpipes at the same boost will make more power by increasing VE but will increase turbo shaft speed due to the increased VE, engine strain will be similar to the previous lower power level from a thermal perspective. Downpipes at stock power levels will decrease required boost to achieve said power, decreasing shaft speed and increasing turbo/engine reliability.

Regardless, you'll want/need a tune with the downpipes, but that tune doesn't have to be anything other than disabling the O2 codes in the flash. The BT cable can do that free with TunerPro.

[ConradConrad]

Originally Posted by FCobra94

How can anyone be "over it" when it comes to a tune? I just don't get it.

1) having to take it out everytime I got to the dealership for service due to possible voiding of warranty

2) constantly chasing a weak link of either a plug, injector, vanos this or that

3) eating through tires like nobodies business because its very difficult to drive normal with a tune esp when you have a 30 mile commute to work each way

4) knowing that increasing the boost will decrease the lifespan of the vehicle

5) Im out of warranty

6) did I mention taking it out of the car everytime you go to the dealership*

* some of you leave it in when you go in for service, good for you not worth a warranty to me.

Really just wanted a little something, I was looking for a little more exhaust note and maybe something that would make the car feel a tad different when I got on it- sorry I dont want to run a tune. If something does exist like that let me know.

Im not bashing tunes just not my cup of tea right now in this car, when I get another 335 with low miles and a full warranty again Ill be back at it till then....

[ConradConrad]

Originally Posted by V8bait

Regardless, you'll want/need a tune with the downpipes, but that tune doesn't have to be anything other than disabling the O2 codes in the flash. The BT cable can do that free with TunerPro.

Is this the same as a DP fix from BMS?

[335NJ]

Originally Posted by ConradConrad

Is this the same as a DP fix from BMS?

No, A DPFix "mimics the o2 signal" to show readiness for emissions/diagnostics testing. The tunes that clear the codes, do just that, they clear the CEL so you don't have to stare at it.

OP, a buddy of mine has catless downpipes, and no tune, with no issues.

[cstmx_ryder]

If you're looking for a different exhaust note, why not just do the golf-tee mod? Should cost less than $5....

[Cloud9blue]

1) having to take it out everytime I got to the dealership for service due to possible voiding of warranty

If you are out of warranty and still going to dealer for service, you are just throwing money away for some free coffee and loaner cars. Find a reputable private shop or learn to DIY.

2) constantly chasing a weak link of either a plug, injector, vanos this or that

If your car has problem, your car has problem, tuned or stock boost.

3) eating through tires like nobodies business because its very difficult to drive normal with a tune esp when you have a 30 mile commute to work each way

Need to learn how to modulate throttle... It is not an on/off switch. And if you really cares, get a square tire setup, so you can rotate the tires. N54 is one of the smoothest engine out there if properly tuned, so if you can't drive this normally, not sure if you should be driving...

4) knowing that increasing the boost will decrease the lifespan of the vehicle

The first thing that fails on this engine is the wastegate, and boost level doesn't really effect the lifespan of that. Unless you run the engine with no boost, so the wastegate never moves

5) Im out of warranty

See #1

6) did I mention taking it out of the car everytime you go to the dealership*

See #1

[AS4EX]

Originally Posted by ConradConrad

1) having to take it out everytime I got to the dealership for service due to possible voiding of warranty

4) knowing that increasing the boost will decrease the lifespan of the vehicle

5) Im out of warranty

6) did I mention taking it out of the car every time you go to the dealership*

* some of you leave it in when you go in for service, good for you not worth a warranty to me.

....when I get another 335 with low miles and a full warranty again Ill be back at it till then....

By no means am I trying to be a jerk here, but you have my scratching my head with what you said.

4) I don't think you fully understand how strong and reliable your engine is. By the sound of it, whatever vehicle you had previously I'm guessing you had issues with, thus making you weary this time around? You'll have issues with any engine, it comes down to how you maintain it. Additionally, most tunes, if not all, have multiple maps, therefore you don't need to be on the one that will give you the most tire shredding power, but enough to put a smirk on your face.

5) You're out of warranty, but you also don't want to void your warranty. Uhm....?

6) What are you doing that is making you take the car to the dealer so often? Most maintenance issues with these cars can be done in a personal garage, saving you hundreds if not thousands. It's not any harder to work on because it says BMW, it's usually just more time consuming.

"When you get into another 335i with warranty you'll tune again." This completely contradicted your intro, #4, and somewhat #6, including what you could consider #7.


Now would be the time to have fun with the car and tune it and whatever you want, from what your telling us. Then when you plan on getting another one with warranty, don't tune it, don't DP it, so you can enjoy not voiding your warranty since you have "been there and done that".


Edit: Cloud9 beat me to it!

[ajsalida]

Originally Posted by ConradConrad

1) having to take it out everytime I got to the dealership for service due to possible voiding of warranty

If you care about doing this you'll have to take out the DP's too. And they are a LOT harder than a tune to remove.