Lessons learned (hpfp, dp's, 335, etc

[Eyeman]

1. Don't install aftermarket downpipes unless you want to fight with BMW.

I had to contact BMW NA, agree to run extra tests that I might have to pay for, etc. Finally they replaced my hpfp and reinstituted my previously "voided" hpfp warranty. If I have another one of the known problems with my car (fuel injectors, etc) I'll have to fight with them again. Unless you seriously need those few extra hp, why do downpipes. If I remove mine now I'm sure it would not change how BMW views my car since it's documented that it has been modified.


2. All N54 ecu's are not the same.

I was given a 335 sedan while my car was in the shop. I'm sure the tuners understand this better than I do or maybe they disagree, but in my mind there is no way that my ecu could ever adapt and give me similar day to day driving characteristics to what this car had. It had very significant lag, especially while shifting. I'd say that in DS mode it performed similarly to a 135 in D mode. I'm sure some will say I'm just confused due to the weight of the car, etc. No way. For example I assume all 135's often get that little push from their car when coming to stop, caused by our cars downshifting. The 335 never did this. Maybe this courtesy car was just exceptionally adapted in it's 7500 miles due to being used softly? Maybe top end performance was the same but it just didn't have that "want to go" sensation that our cars have, it kind of just felt like it wanted to cruise along.

3. Features better in the 335:
a. Side mirrors, too small in my 2008 135
b. high speed stability might be better due to the 135 short wheelbase
c. seat belt is much easier to reach
d. headlights and hood are better looking

4. Surprising differences:
a. I'd swear the 335 seat bottoms were shorter (both non-sport)
b. I had heard the 335 interior was better but I didn't like it's dash, radio display angle, cup holders, etc.
c. it's funny to me how big our DTC button is vs theirs
d. for sure my speedometer read high stock, the 335 seemed the same. I frequently found myself going well faster than I thought. My wheel change (bigger rear total diameter, similar front) should make my car register even higher but I don't seem to have the issue in my car now. I even wonder if it's my exhaust helping me appreciate my speed.

Of course I'm biased but I like most everything better about our 135's with performance and exhaust sound being the biggest differences.

[acivick]

Not sure if the different gear ratios on the 335i may have had something to do with your experience with it.

[Eyeman]

Could be, do 135 vs 335 steps have different gear ratios?

[Mega Man]

Originally Posted by Eyeman

1. Don't install aftermarket downpipes unless you want to fight with BMW.

Good to know...I was going to go with CP-E...but honestly, I don't want to fight with BMW if I have an HPFP issue.

[jibaholic101]

how exactly does downpipes effect your HPFP?

[SB135]

How did they know you had downpipes? Did you not remove them before you went to the dealer?

Originally Posted by Eyeman

1. Don't install aftermarket downpipes unless you want to fight with BMW.

I had to contact BMW NA, agree to run extra tests that I might have to pay for, etc. Finally they replaced my hpfp and reinstituted my previously "voided" hpfp warranty. If I have another one of the known problems with my car (fuel injectors, etc) I'll have to fight with them again. Unless you seriously need those few extra hp, why do downpipes. If I remove mine now I'm sure it would not change how BMW views my car since it's documented that it has been modified.


2. All N54 ecu's are not the same.

I was given a 335 sedan while my car was in the shop. I'm sure the tuners understand this better than I do or maybe they disagree, but in my mind there is no way that my ecu could ever adapt and give me similar day to day driving characteristics to what this car had. It had very significant lag, especially while shifting. I'd say that in DS mode it performed similarly to a 135 in D mode. I'm sure some will say I'm just confused due to the weight of the car, etc. No way. For example I assume all 135's often get that little push from their car when coming to stop, caused by our cars downshifting. The 335 never did this. Maybe this courtesy car was just exceptionally adapted in it's 7500 miles due to being used softly? Maybe top end performance was the same but it just didn't have that "want to go" sensation that our cars have, it kind of just felt like it wanted to cruise along.

3. Features better in the 335:
a. Side mirrors, too small in my 2008 135
b. high speed stability might be better due to the 135 short wheelbase
c. seat belt is much easier to reach
d. headlights and hood are better looking

4. Surprising differences:
a. I'd swear the 335 seat bottoms were shorter (both non-sport)
b. I had heard the 335 interior was better but I didn't like it's dash, radio display angle, cup holders, etc.
c. it's funny to me how big our DTC button is vs theirs
d. for sure my speedometer read high stock, the 335 seemed the same. I frequently found myself going well faster than I thought. My wheel change (bigger rear total diameter, similar front) should make my car register even higher but I don't seem to have the issue in my car now. I even wonder if it's my exhaust helping me appreciate my speed.

Of course I'm biased but I like most everything better about our 135's with performance and exhaust sound being the biggest differences.

[Eyeman]

Exactly Jib, that's how I finally got them to replace mine. I guess they ran tests that showed that my mods did not cause my problem. I would have just bought an aftermarket fuel pump but that's not yet an option so I figured it was worth the fight.

SB135, nope. I guess that's another option if you really feel dps are worth it. Of course you could also be held liable for fraud if you remove a mod and claim you never had it and later are somehow proven wrong.

[jibaholic101]

yeah thats some bullshit
sounds like its time to change dealers and get with a mod friendly SA

[Eyeman]

My vin# now shows up in any dealer's database as modified.

[SB135]

Originally Posted by Eyeman

Exactly Jib, that's how I finally got them to replace mine. I guess they ran tests that showed that my mods did not cause my problem. I would have just bought an aftermarket fuel pump but that's not yet an option so I figured it was worth the fight.

SB135, nope. I guess that's another option if you really feel dps are worth it. Of course you could also be held liable for fraud if you remove a mod and claim you never had it and later are somehow proven wrong.

I'm actually looking for some downpipes...care to sell yours?

[acivick]

Originally Posted by Eyeman

Could be, do 135 vs 335 steps have different gear ratios?

Just looked at them and apparently not, the only difference is between manual and step. Second guess is different software version, 29.x was apparently a pig.

[Eyeman]

SB135, no thanks. BMW already knows I have downpipes, if I remove them I doubt it will change my status with them. Plus I have already fought it and got my hpfp warranty renewed.

Acivick, that's what I thought. I honestly think the day to day performance is programmed differently in 135's vs 335. The difference is just that great.

[My135]

Eyeman, I am glad that you won the battle against BMW and I am proud of you.

I have to agree with you that most BMW dealers in down are not very mod friendly. I don't think BMW understoond people moding their cars are free advertising for them becase they will brag about how fast and how many hp/tq their BMWs can run and make.

Good luck and hoefully I got time to check out your KW V1 suspension again in the near future.

[Mega Man]

Eyeman, how did you fight them on the downpipe/HPFP issue. I'm interested to know, because I'd like to get an exhaust upgrade and I am looking into CP-E. However, I don't want to completely f*ck my warranty for an upgraded exhaust! Since we are known to have multiple HPFP issues, I don't want to be s#it out of luck when my HPFP craps out on me again and not necessarily because of an exhaust!

[My135]

Cat back exhaust should not have any problem in getting warranty repair. It should only apply to significant hp/tq upgrade mods (like DP, ECU reflash ... etc.) mostly.

[Eyeman]

My135, thanks, funny enough, I think the United is glad I got my hpfp warranty back too. This stuff is BMW NA policy. Seems a bad decision to me. Modded cars are good advertising and trying to fight to not replace known bad parts is bad business IMO. Actually though, I'm sure BMW knows what they are doing and it's just a business decision, probably a wise one. Who knows.

MegaMan, at my first SES visit (with my downpipes on the car), my car was wrote up as modified and entered into the BMW database. They call it "voiding your drivetrain warranty" (I think they "voided" my suspension warranty too..lol) That's really is not what is happening, basically they are just self establishing in their opinion that they don't want to cover it. We still have legal options. I started just by calling BMW NA a few times, first to be told to try other dealers (that won't work once they've entered your VIN into the database). My second call I was referred up a level or two and they opted for me to bring my car back to the dealer of my choice for a no charge service so they could "figure out what was happening with my car". I'm pretty sure a national rep looked at my car that day and they supposedly even did more tests which I authorized with another specialized technician. The final decision (I guess?) after my car being at the dealer from Friday until Wednesday was to reinstitute my hpfp extended warranty. For sure I have a new hpfp!

Stick with just a downpipe back exhaust and removable mods unless you want to get in this situation yourself or unless you really want to join the "400whp club". That's why I'm not too upset about all this, so far I'm just working on my supporting mods. I plan to add my tune/meth last. In my mind, that's when I'll quit trying to fight for my warranty if something goes wrong.

[Genericuser1]

Anytime you install aftermarket parts be prepared to fight the manufacturer. Especially if you do anything to the powertrain and something that fails could be traced back to teh general vicinity of the after market part.

You do know if you modify the ECU and the engine blows up you will not be covered right?

[evilstib]

Originally Posted by Eyeman

1. Don't install aftermarket downpipes unless you want to fight with BMW.

I had to contact BMW NA, agree to run extra tests that I might have to pay for, etc. Finally they replaced my hpfp and reinstituted my previously "voided" hpfp warranty. If I have another one of the known problems with my car (fuel injectors, etc) I'll have to fight with them again. Unless you seriously need those few extra hp, why do downpipes. If I remove mine now I'm sure it would not change how BMW views my car since it's documented that it has been modified.

Any Dyno / estimates on the gains from installing DPs?