Getting the old girl remapped... I should have learned my lesson by now...
- Thread starter Maniac
- Start date
Hi Maniac what year is your 35i and I know this will sound a daft question but what reason are you doing it and I ask because I have a 2009 35i and am wondering what benefits there are as in standard mode it goes like a bloody rocket 
so it would be good to know as this is an area that I have no knowledge of, also if you do it can the car take it without changing or upgrading any components?
Thanks
so it would be good to know as this is an area that I have no knowledge of, also if you do it can the car take it without changing or upgrading any components?Thanks
Thought it worth quoting directly from 35i-nut's link below. This perfectly sums up how I feel about my own remap on my N52 3.0Si engine:
. . . takeoffs are completely smooth and fuss-free, as the ignition timing and fueling remains standard below 3000 revs or so. Once beyond that point, the extra power and torque really make themselves felt, although at no point does my car feel like a traditional turbo-charged motor. There is no real discernable step in power delivery - it's just one constant push towards the horizon. Gear changes are effected smoothly, with no jerks or hesitation. This is how I've always imagined the best remaps to be - an enhancement of the standard car's driving characteristics, with no drawbacks. And really, there are ZERO drawbacks.
. . . takeoffs are completely smooth and fuss-free, as the ignition timing and fueling remains standard below 3000 revs or so. Once beyond that point, the extra power and torque really make themselves felt, although at no point does my car feel like a traditional turbo-charged motor. There is no real discernable step in power delivery - it's just one constant push towards the horizon. Gear changes are effected smoothly, with no jerks or hesitation. This is how I've always imagined the best remaps to be - an enhancement of the standard car's driving characteristics, with no drawbacks. And really, there are ZERO drawbacks.
andya1 said:Hi Maniac what year is your 35i and I know this will sound a daft question but what reason are you doing it and I ask because I have a 2009 35i and am wondering what benefits there are as in standard mode it goes like a bloody rocket
Thanks
This engine and gearbox have been proven up to 400hp or so without any need for additional components and with no impact on longevity. As someone said earlier cars are routinely tuned down to fit a particular price point and for numerous other reasons.
I'm doing it as the car has always felt strangled at higher revs (motorways for example) and a higher boost/tune will help with this.
As for the 35is comments above my figures aren't accurate they're just ballpark. As the 35i and iS aren't that much different there will likely be similar outcomes but not the same. Other than a slightly louder exhaust.. There may be other differences in the iS so I've read over the years but there's a lot of confusion and disinformation around it as a subject as Bmw never publishes a full list of differences to my knowledge. As I already have adaptive suspension and DCT after the remap it should be a similar car...
In any event I'm not trying to match an iS, I'm simply remapping which will give me similar performance but for the main reason outlined above, better high Rev and overall performance.
+1andya1 said:Thanks for the reply it makes sense, I would love to know your thoughts when you have had it done as it is tempting
I had mine done and it unleashes another element to the car....
Driving around town its absolutely no different.... Mid range torque is vastly improved,you really have to be careful is Sport + as it will start to spin wheels when you least expect it.... Top end is improved,but realistically you never need to rev the car hard as time you have got to 4k and its popping through the gears,the car is flying..
Mines approx 395 bhp....
Like Gary says,its hard to pin down differences in 35i and 35is........
The exhaust is different,but i have read the cats have higher flow and the intercooler has better flow rates as standard.. Not sure how true that is though..
Driving around town its absolutely no different.... Mid range torque is vastly improved,you really have to be careful is Sport + as it will start to spin wheels when you least expect it.... Top end is improved,but realistically you never need to rev the car hard as time you have got to 4k and its popping through the gears,the car is flying..
Mines approx 395 bhp....
Like Gary says,its hard to pin down differences in 35i and 35is........
The exhaust is different,but i have read the cats have higher flow and the intercooler has better flow rates as standard.. Not sure how true that is though..
One thing a lot of you will be missing out on is linear throttle mapping. Most tuning companies will be using a default map that retains the very sensitive throttle mapping from the stock car.
In stock form the throttle pedal mapping is giving you 100% throttle at only 40% pedal travel. That really doesn't help when you have a load more power on tap!
If the tuner is capable of tweaking the tune to give you a more linear throttle then I would recommend it. It makes the car feel sluggish until you re-wire you brain to apply more pedal but once you have re-learned it becomes much easier to modulate the throttle.
There's really no need to remove the ECU. I would be wary of any company that still thinks that this is required.
Yes you are correct, ECU program and exhaust. There really is a lot of misinformation about the differences, I think BMW salesmen have a lot to answer for!
In the US the 35i and 35is have different brakes but in the EU both models have the same upgraded brakes.
The primary cats are the main restriction in the exhaust, the rest of the system is said to be very capable at higher power levels. Higher flow cats in the 35is would explain the change in exhaust note.
I don't think there's much extra tuning headroom in the 35is exhaust, it still has to meet the same factory requirements regarding emissions so you aren't going to see the same gains as people completely removing their primary cats.
The intercooler is a larger problem with the N54 engine but since we have a nice cool climate it's not as essential.
In stock form the throttle pedal mapping is giving you 100% throttle at only 40% pedal travel. That really doesn't help when you have a load more power on tap!
If the tuner is capable of tweaking the tune to give you a more linear throttle then I would recommend it. It makes the car feel sluggish until you re-wire you brain to apply more pedal but once you have re-learned it becomes much easier to modulate the throttle.
Timdon said:
There's really no need to remove the ECU. I would be wary of any company that still thinks that this is required.
techathy said:
Yes you are correct, ECU program and exhaust. There really is a lot of misinformation about the differences, I think BMW salesmen have a lot to answer for!
In the US the 35i and 35is have different brakes but in the EU both models have the same upgraded brakes.
The primary cats are the main restriction in the exhaust, the rest of the system is said to be very capable at higher power levels. Higher flow cats in the 35is would explain the change in exhaust note.
I don't think there's much extra tuning headroom in the 35is exhaust, it still has to meet the same factory requirements regarding emissions so you aren't going to see the same gains as people completely removing their primary cats.
The intercooler is a larger problem with the N54 engine but since we have a nice cool climate it's not as essential.
It does make you wonder that if you are buying used and prefer manuals the 35i with some choice mods such as exhaust, or at least cats and a remap will effectively give you a 35is manual for less money than buying an equivalent age mileage 35is.
Has anyone got circa 400bhp out of a 35i with mods as opposed to the 35is?
Has anyone got circa 400bhp out of a 35i with mods as opposed to the 35is?
just had a quick nosey on trader and 35i manuals are considerably cheaper and much more plentiful than the equivalent 35is as a bit of a die hard manual fan i seriously think this is the route i would go down, its always bugged me they don't make a 35is manual and there seem to some very well specced 35i manuals out there. I am not sure if cosmetically the bumpers etc differ between the models or if there are differences in the suspension (i suppose i could check real oem on that) but if you planned to upgrade the suspension anyway that would become a mute point.
The 35is has EDC has standard...
And i think its a great system that really works well... Road use to mild track use is easily covered.
But there are many 35i out there that have EDC fitted too if thats your bag.
I guess the 35is will always bring a premium being the top model in the range when it comes to resale,so that might be a point worth considering...
But spend wisely on a 35i in your preffered manual,and your could have a very fast car at reasonable money...
And i think its a great system that really works well... Road use to mild track use is easily covered.
But there are many 35i out there that have EDC fitted too if thats your bag.
I guess the 35is will always bring a premium being the top model in the range when it comes to resale,so that might be a point worth considering...
But spend wisely on a 35i in your preffered manual,and your could have a very fast car at reasonable money...
As for differences between the 35i and 35iS I really have no idea beyond the fact DMS who seem to know a thing or two told me they get maybe 375bhp from a 35i and 405bhp from a 35iS due to 'subtle' differences between the cars.
DMS didn't really go into detail but the 325d LCI (204bhp) allegedly has the same engine as the 330d LCI (245bhp) and forums say the only difference is a map.
In that case why did DMS get 280bhp from a 325d and 305bhp from my 330d. The answer according to DMS was, again, 'subtle' differences between the two ...
When not in warranty I may have a play :evil:
DMS didn't really go into detail but the 325d LCI (204bhp) allegedly has the same engine as the 330d LCI (245bhp) and forums say the only difference is a map.
In that case why did DMS get 280bhp from a 325d and 305bhp from my 330d. The answer according to DMS was, again, 'subtle' differences between the two ...
When not in warranty I may have a play :evil:
MACK said:
400bhp with no mods is easily achievable. I can't remember the record for a fully stock car exactly but north of 450bhp, you will just have heat problems without an upgraded intercooler.
There's a good topic here from one of the better tuners on the N54 platform: http://e89.zpost.com/forums/showthread.php?p=17255975
Be aware that most people in the USA quote wheel horsepower whereas it's common in the UK for people to use brake horsepower which is 15%~ higher. Gives you a good idea of the potential of the engine in our cars.