ECU tune

[Solarium]

So I'm about the be done with my lease in September and is thinking of keeping the M4. I feel like modding the shit out of my car once I own it. A few questions for the pros:

1. Is there a tune that you can deactivate prior to coming into the dealership so that they won't detect it? I'm planning on getting a CPO warranty.
2. What's the best tune?
3. What's the next mod after getting a tune? Exhaust? Downpipes? Intakes? Methanol injection? Do these also void the CPO warranty on the car?
4. Does modding my M4 *HEAVILY* decrease the sale value eventually? A few thousand is OK, but it's like $10k vs $20k after 5 years then will be a problem.

Thanks all

[F80Moe]

1. All tunes can be detectable if they dig deep (Some tunes offer quick map switching via phone/tablet)
2. No best tune, most known:
BM3, BPM, VF, JB4.. (search many threads on this)
3. DP's can get you more boost (stage 2) - I would recommend tires since traction would be an issue
4. Basic bolt ons IMO would not heavily affect sales value

PS: Wrong section for this thread should be Engine/ Exhaust modifications

[Solarium]

Originally Posted by F80Moe

1. All tunes can be detectable if they dig deep (Some tunes offer quick map switching via phone/tablet)
2. No best tune, most known:
BM3, BPM, VF, JB4.. (search many threads on this)
3. DP's can get you more boost (stage 2) - I would recommend tires since traction would be an issue
4. Basic bolt ons IMO would not heavily affect sales value

PS: Wrong section for this thread should be Engine/ Exhaust modifications

Just found that forum section Starting a new thread there, mods please merge together/delete this one. Thanks

[CigarPundit]

The “what’s the best tune” question tends to devolve into a bonfire of opinions. I realize that so much has been written on the strengths and weaknesses of the various tunes that being told to use the search function is dissatisfying. But it’s a personal choice involving many factors that only you can make, so spending some time doing some searching and reading will serve you well. There are no shortcuts, unfortunately.

There is no risk-free tune from a warranty perspective. If BMW tries to find it, they will.

Any flash tune can be flashed back to stock. And piggy backs can be removed. But ultimately still detectable.

I think tuning creates no resale value enhancement, unless you get lucky and find just the right person. The expectation should be zero enhancement and a possible reduction in value. I would not buy a used tuned car for lots of reasons.

IMO, exhaust (cat back) and tune are the first two, then suspension if you don’t mind the clearance downside. Then cosmetic enhancements. Downpipes and turbos take you to the next level, but also get you into an area where you are investing so much money in the car and inviting so many problems that you might want to consider a different car.

YMMV.

[BMWRX]

Originally Posted by CigarPundit

I think tuning creates no resale value enhancement, unless you get lucky and find just the right person. The expectation should be zero enhancement and a possible reduction in value. I would not buy a used tuned car for lots of reasons.

I have tuned my last few cars yet I'm of the same opinion as regarding buying a car that has been tuned. I suppose the enjoyment from a tuned car far outweighs any potential reduction in resale value.

As for which tune to go with, I used a JB4 (in my E82 N54 135i) for eight years and it didn't miss a beat. You can turn it on and off from the steering wheel controls in seconds and the dealership has never mentioned its existence.

However, I have never relied on a warranty claim, so there was no reason for the dealership to be concerned, even if they did find the tune. It may be a completely different tale if something had gone wrong and I need BMW's assistance in rectifying the matter.

[Solarium]

Originally Posted by CigarPundit

The “what’s the best tune” question tends to devolve into a bonfire of opinions. I realize that so much has been written on the strengths and weaknesses of the various tunes that being told to use the search function is dissatisfying. But it’s a personal choice involving many factors that only you can make, so spending some time doing some searching and reading will serve you well. There are no shortcuts, unfortunately.

There is no risk-free tune from a warranty perspective. If BMW tries to find it, they will.

Any flash tune can be flashed back to stock. And piggy backs can be removed. But ultimately still detectable.

I think tuning creates no resale value enhancement, unless you get lucky and find just the right person. The expectation should be zero enhancement and a possible reduction in value. I would not buy a used tuned car for lots of reasons.

IMO, exhaust (cat back) and tune are the first two, then suspension if you don’t mind the clearance downside. Then cosmetic enhancements. Downpipes and turbos take you to the next level, but also get you into an area where you are investing so much money in the car and inviting so many problems that you might want to consider a different car.

YMMV.

Doesn't downpipes have better gains than cat backs? I'm kind of a newbie on this since all my previous cars are leases and I was careful not to go beyond the ECU. What are the average cost and HP boost I should expect as well?

Originally Posted by BMWRX

I have tuned my last few cars yet I'm of the same opinion as regarding buying a car that has been tuned. I suppose the enjoyment from a tuned car far outweighs any potential reduction in resale value.

As for which tune to go with, I used a JB4 (in my E82 N54 135i) for eight years and it didn't miss a beat. You can turn it on and off from the steering wheel controls in seconds and the dealership has never mentioned its existence.

However, I have never relied on a warranty claim, so there was no reason for the dealership to be concerned, even if they did find the tune. It may be a completely different tale if something had gone wrong and I need BMW's assistance in rectifying the matter.

I used JB3 in my 335i previously as well, and had a good experience using them even selling it years after for a good resale value. I'm just concerned about M4's turbo, my previous 335i's had issues with the water pump and turbo's failing, and my experience with BMW's in general is that if it's a turbo it's bound to have problems after 3 years. I'm guessing the M4's much better made than the 335i's though. BMS's also make the methanol injection system, akin to the water injection on the GTS, what's your opinion of it?

[CigarPundit]

Originally Posted by Solarium

Doesn't downpipes have better gains than cat backs? I'm kind of a newbie on this since all my previous cars are leases and I was careful not to go beyond the ECU. What are the average cost and HP boost I should expect as well?

IMO, cat back exhaust is purely for sound and looks. I have the AA midpipe and axle back. They say it makes 18hp, but not in my experience (and not according to multiple runs on two different dynos). I like the sound of the exhaust note better now, and the volume is fine, but I have noticed a drone under power between 2000-2300 rpm that wasn't there before. Some would be totally fine with this, others wouldn't. Since I know it makes virtually no power, I'm considering swapping it out for my stock mid section that has a resonator to see how I like the sound in that configuration.

Downpipes probably do make some power (maybe 10-15 hp--I have no personal experience, but this is what I hear), but you now have a totally illegal cat-less car that will most definitely not pass smog. Plus, you tend to get an unpleasant exhaust fume smell without the cats. For me, these tradeoffs aren't worth it.

There are lots of ways to make power, but the car starts off pretty awesome, and doing a tune is probably the best bang for the buck to make some additional power without getting into a more involved and expensive process with hardware changes (downpipes, turbos).

Just depends on what you want.

[mike@x-ph.com]

1. Is there a tune that you can deactivate prior to coming into the dealership so that they won't detect it? I'm planning on getting a CPO warranty.

If you have an ECU flash, load the stock map before your visit
if you have a piggy, remove it before your visit


2. What's the best tune?

Depends on what you are looking for and your ultimate mod goals

3. What's the next mod after getting a tune? Exhaust? Downpipes? Intakes? Methanol injection? Do these also void the CPO warranty on the car?

Charge pipe and methanol injection for max power increase

4. Does modding my M4 *HEAVILY* decrease the sale value eventually? A few thousand is OK, but it's like $10k vs $20k after 5 years then will be a problem.

It wont decrease your car's value, i remove all mods before i sell the car and sell them on the forums. You would get 50% of what you paid back