135i Turbo Engine (N54 / N55) *General Questions Thread*

[The1]

Originally Posted by Impervious

Carbon buildup... is it a legit concern or not? What exactly is it? Ways to cope with it?

the carbon buildup is common on every single engine. it's the frequency in which our cars accumulate it on the intake vavles that is the problem.

what happens is that a normal, or older engine then the direct injection engines we have today, is that the fuel injectors are aimed into the intake manifold where they consistently keep a flow of fluid going through, thus they are helping keep the valves and intake cleaner.

on our engines however, since the injectors are in the combustion chamber, they do not clean the intake valves off sufficiently since there is no fuel flow into the intake. all that's happening is moist carbon is going up the intake a bit and settling on the valves.

this build up makes them heavier and thus slower reacting, this will deteriorate some throttle response, as well as hurt gas mileage and add wear and tear.

to avoid this, make sure to put Teir 1 fuels in, eg: shell, petro, esso, i think BP and a few others. avoid mom and pop shops as they don't have cleaning agents added to the fuel.

the best way to know if your system has some carbon buildup going on is if you have a slight stutter going on when you're at wide open throttle.

I had this happen and rand a fuel system cleaner (bmw doesn't recommend this) and that stutter went away pretty quickly. I never had the problem again as i decided to get a lot more selective about the types of fuels i was putting in the car.

It's easy to stay on top of it, just avoid bad fuel and you shouldn't really have any issues.

[bryce]

Originally Posted by The1

does that mean a new car in the future?

yessir. looking at e90 335i....i need the backseat and rear doors now

Originally Posted by Impervious

Carbon buildup... is it a legit concern or not? What exactly is it? Ways to cope with it?

it's a legit concern. an oil catch can is a good start on reducing it. i've heard mixed information about seafoam. some people swear by it, others wisely look at the ingrediants or components and decide it's not worth it. i have yet to form my opinion on seafoam but i do run an OCC

Originally Posted by TZANIDO777

Hey Bryce, which suspension would you say is more worth the money, im stuck between the SA Koni yellow coilover kit with costum swift spring rates http://www.hpashop.com/product.sc?pr...categoryId=166
or the AST 4100 SA coilover kit with costum spring rates?http://www.hpashop.com/product.sc;js...categoryId=166 im looking for a half daily driver and half track use, Thanks for the help

i'm not 100% up on suspension components, but i do like koni yellow shocks. i think they're a great shock to add to lowering springs (i happen to have a set that i was going to use on my 135i)

the argument for coilovers is the ability to adjust ride height/dampening/rebound (which koni's can do some of). i didn't want coilovers mainly because of the higher cost (koni/h&r setup is pretty reasonable). i've heard from my local race shop that coilovers can be corner balanced better than koni/springs can

Originally Posted by The1

the carbon buildup is common on every single engine. it's the frequency in which our cars accumulate it on the intake vavles that is the problem.

what happens is that a normal, or older engine then the direct injection engines we have today, is that the fuel injectors are aimed into the intake manifold where they consistently keep a flow of fluid going through, thus they are helping keep the valves and intake cleaner.

on our engines however, since the injectors are in the combustion chamber, they do not clean the intake valves off sufficiently since there is no fuel flow into the intake. all that's happening is moist carbon is going up the intake a bit and settling on the valves.

this build up makes them heavier and thus slower reacting, this will deteriorate some throttle response, as well as hurt gas mileage and add wear and tear.

to avoid this, make sure to put Teir 1 fuels in, eg: shell, petro, esso, i think BP and a few others. avoid mom and pop shops as they don't have cleaning agents added to the fuel.

the best way to know if your system has some carbon buildup going on is if you have a slight stutter going on when you're at wide open throttle.

I had this happen and rand a fuel system cleaner (bmw doesn't recommend this) and that stutter went away pretty quickly. I never had the problem again as i decided to get a lot more selective about the types of fuels i was putting in the car.

It's easy to stay on top of it, just avoid bad fuel and you shouldn't really have any issues.

^great info!

[The1]

Originally Posted by bryce

yessir. looking at e90 335i....i need the backseat and rear doors now

it's a legit concern. an oil catch can is a good start on reducing it. i've heard mixed information about seafoam. some people swear by it, others wisely look at the ingrediants or components and decide it's not worth it. i have yet to form my opinion on seafoam but i do run an OCC

Need is such a strong word..... just buy an old corolla and keep the 1er


I agree with you on the seafoam. I have an older higher mileage Jeep that i use daily (in winter anyhow) and i'm testing seafoam out on it before i go anywhere near my car with it.

So far i've done a bit in the oil, didn't really notice any difference.

and a bit in the gas tank, this resulted in a lot of carbon coming out the back into a snow bank and looking really gross, so it does do something.

and i haven't really taken the time to rip apart the air intake yet to pour it in, or do the break booster vacuum line, it just got too cold out.

I did throw a check engine light for an O2 sensor, however, i have a small oil leak and the oil drips right on top of the sensor, so i'm not sure which was at fault.

Overall, the seafoam did take some carbon out of the jeep, i'm just not sure where it came from as the injectors in it are aimed down the intake and onto the valves, so it could have cleaned them off.

I'm still a bit iffy on it, but once i've sent some seafoam through the intake directly, then i'll have a better idea if i want to take a bottle anywhere near my car.

[TZANIDO777]

Originally Posted by bryce

yessir. looking at e90 335i....i need the backseat and rear doors now



it's a legit concern. an oil catch can is a good start on reducing it. i've heard mixed information about seafoam. some people swear by it, others wisely look at the ingrediants or components and decide it's not worth it. i have yet to form my opinion on seafoam but i do run an OCC



i'm not 100% up on suspension components, but i do like koni yellow shocks. i think they're a great shock to add to lowering springs (i happen to have a set that i was going to use on my 135i)

the argument for coilovers is the ability to adjust ride height/dampening/rebound (which koni's can do some of). i didn't want coilovers mainly because of the higher cost (koni/h&r setup is pretty reasonable). i've heard from my local race shop that coilovers can be corner balanced better than koni/springs can



^great info!

Hey Bryce thanks for the advice, but the Koni yellows i showed you are a coilover kit with swift springs, so would i be able to corner balance those?

[The1]

Originally Posted by TZANIDO777

Hey Bryce thanks for the advice, but the Koni yellows i showed you are a coilover kit with swift springs, so would i be able to corner balance those?

You can corner balance anything, it's just easiest with a coil over system as the spring heights are adjustable.

anything that isn't adjustable, you have to get creative to corner balance, like making shims to lift up one spring a little higher then another.

[TZANIDO777]

Okay, thanks for the advice

[bryce]

Originally Posted by TZANIDO777

Okay, thanks for the advice

x2.....thanks The1!

[The1]

no prob. I like to keep an eye on things.

[bryce]

Originally Posted by The1

no prob. I like to keep an eye on things.

it's appreciated

work is too crazy lately for me to stay active and online during the day

[bryce]

bump for teh general intake/exhaust/tube/intercooler/etc thread

[bryce]

Originally Posted by bryce

bump for teh general intake/exhaust/tube/intercooler/etc thread

[Impervious]

Bryce - How do I check to see what fuel pump I have?

[oman135]

when i disable half traction in Manual mode first gear and full throttle there is a bit of lag/jerkness when changing to second gear. i cant really explain what exactly happens. is this normal ? it doesn't happen when i disable full traction

[chachacha28]

1. Is dinan the only company to make an oil cooler for the car? Why is it $1500, just the name?
2. Is an aftermarket intercooler of any benifit for a near-stock engine? (just planning on a tune and full exhaust, keeping catted mids, but catless dp's)
3. Im looking for a chip/programmer/tune that will eliminate my top speed (tires are rated for 300km/h), and give a bump in power (this car is already stupid fast, by far the fastest ive ever owned, just looking for better triple digit acceration), but i was wondering if any companies offered an integrated turbo timer? I smoke, so i usually smoke a cigarette before and after a drive to let the car warm up and cool down, but... a turbo timer would be more convenient. any suggestions?

I know this is the powertrain forum, but i saw some suspension talk, so ill ask.

4. Front sway bar... M3 or aftermarket (brand suggestion?) what about rear sways? Ive even heard of people just removing them?
5. I have H&R Lowering springs, Koni Yellows seem to be mated to these pretty often, any alternatives?
6. Are Cool Carbon pads good pads for a DD? Alternatives?

and finally...

7. Any easy way to shed weight without making my car look like a teenagers first honda?

[bryce]

Originally Posted by Impervious

Bryce - How do I check to see what fuel pump I have?

did you buy the car used? see if you can find the maintenace records from the previous owner. it was pretty simple for me to find mine; just looked at the selling dealership and called them up. they emailed me the previous records. of course, i'm on a new fuel pump since then (933)

Originally Posted by oman135

when i disable half traction in Manual mode first gear and full throttle there is a bit of lag/jerkness when changing to second gear. i cant really explain what exactly happens. is this normal ? it doesn't happen when i disable full traction

i don't know too much about the automatic 135i's (or dct or steptronic, whichever names you prefer). i know first gear in my 6mt is kind of jerky sometimes

Originally Posted by ezeedee

1. Is dinan the only company to make an oil cooler for the car? Why is it $1500, just the name?
2. Is an aftermarket intercooler of any benifit for a near-stock engine? (just planning on a tune and full exhaust, keeping catted mids, but catless dp's)
3. Im looking for a chip/programmer/tune that will eliminate my top speed (tires are rated for 300km/h), and give a bump in power (this car is already stupid fast, by far the fastest ive ever owned, just looking for better triple digit acceration), but i was wondering if any companies offered an integrated turbo timer? I smoke, so i usually smoke a cigarette before and after a drive to let the car warm up and cool down, but... a turbo timer would be more convenient. any suggestions?

I know this is the powertrain forum, but i saw some suspension talk, so ill ask.

4. Front sway bar... M3 or aftermarket (brand suggestion?) what about rear sways? Ive even heard of people just removing them?
5. I have H&R Lowering springs, Koni Yellows seem to be mated to these pretty often, any alternatives?
6. Are Cool Carbon pads good pads for a DD? Alternatives?

and finally...

7. Any easy way to shed weight without making my car look like a teenagers first honda?

1. stett have released a few oil coolers for the 135i, cheaper and most likely higher performing than teh dinan

2. intercooler will definitely see the best results w/ a tune. i have the big tom, but i used to have the HPF. it's quite a noticeable difference- less heat soak, less reduced performance after a few WOT pulls, stronger top end pull, etc.

3.no built in turbo timers that i've seen. electric water pump makes a turbo timer almost unnecessary. i've tried teh jb+, jb3, jb4, and procede v4/v5. with the new updates to the V5 (Dynamic ignition conrol, traction control based off ignition, etc) it's the best choice CURRENTLY. i think the cobb accessport will gain more popularity, i just think it's too underdeveloped as of yet.

4-6. not the best person to ask suspension, sway bar, etc questions to, sorry

[The1]

I'll sort of chime in about the sway bars....

from what i've read an some personal experience, there are 2 M3 bars that can fit on our cars one is i believe a 26.5 and the other is a 28mm

if you don't plan on modifying the rear sway and aren't going too aggressive with the suspension, it sounds like the 26.5 (or whatever it is) is the better choice.

a few people have experimented with a rear bar, but due to our open differentials, this isn't the best option unless you have a very controlled right foot and don't get on the gas too early. it causes the inside tire to spin more easily in turns.

however, if you end up upgrading your rear diff to a limited slip, a rear sway bar is not a bad option.

if you are on the base model 135, i believe there isn't a rear sway, however on the sport package and M package, there is a 15mm one on the car from factory.

some of the racing companies have removed their rear bar and been happy with the results, but others have left it in, so it will be down to personal preference, however, it's something like a 7 hour install time, so pick one and stick with it

Don't quote me on any of this information as it is something i have only limited experience with at this point in time.

I went with the larger M3 bar, and will be installing the M3 rear bar, but i plan on being semi aggressive with my suspension setup and doing control arms and all sorts of goodies.

But until they are in the vehicle, i can only tell you what i have, and not how well it works, other then by what i've read. With the exception on the M3 front bar, which i did install, and sort of liked it and regretted it. It was too aggressive for the stock suspension, but it's only a matter of time before i have a million other parts installed, and i will be able to make the bar work for me rather then against me.

[The1]

Originally Posted by ezeedee

7. Any easy way to shed weight without making my car look like a teenagers first honda?

best way to shave weight in the car is to just not leave anything in the car, any little thing that you leave in the trunk all the time or the back seat, is just added weight. Yes, i know this isn't really weight saving, but it's weight conservation.

Two of the quickest ways to actually make the car lighter however are an after market exhaust system, which some of the lightest ones will take about 40lbs off the car

and secondly, getting rid of the stock battery and substituting a light weight battery in it's place, which can be good for about 30-50lbs of weight savings.

Both of these options take a lot of weight off, but both take most of the weight off the rear of the car, and can mess with the geometry a little bit, so just be conscious of this. maybe offset the weight with a carbon fiber hood, and just paint it so nobody knows.

Lighter wheels and getting rid of the run flat tires transforms the car. I measured the rear wheels with really light weight ones against stock, and i was close to 15lbs per rear wheel and about 8-10 per front wheels, this does not seem like a lot, but it is rotating and unsprung mass and it makes a massive difference and you can feel it in many ways.

after that, there's a carbon fiber trunk, and then taking out the rear seat, and substituting front seats with racing seats.

there is a carbon fiber front wide body kit for the car as well that replaces the front fenders and bumper for added lightness.

All this is going to cost a lot though.




and as Bryce said, there is a Stett oil cooler on the market, I have it, but as my car is no longer on the road ( long story) i have not really had an opportunity to test it out and it's cooling abilities. It will be transferring onto my next car and hopefully i'll have a chance to do a good test of it.



Be careful of aftermarket break pads, I would recommend reading in of of the stickied sections about the breaks and their problems when on the track with track pads, People have made shims to combat some problems and it sounds like it's been pretty successful.


Hope this helps a weeee bit.

[Unkie]

How bad is the smell and exhaust dust with de-catted downpipes?
My other car (Mitsu Evo) has a high flow cat and the exhaust smell is already noticably worse...
I've got a 135i convertible, and prefer not to have an interior full of soot every 100kms, or feel like I'm dying of carbon monoxide poisoning just going down to the shops :P

If its that bad I'll just go with high flow rather than no cats

[bryce]

Originally Posted by Unkie

How bad is the smell and exhaust dust with de-catted downpipes?
My other car (Mitsu Evo) has a high flow cat and the exhaust smell is already noticably worse...
I've got a 135i convertible, and prefer not to have an interior full of soot every 100kms, or feel like I'm dying of carbon monoxide poisoning just going down to the shops :P

If its that bad I'll just go with high flow rather than no cats

i have catless downpipes w/ the stock exhaust and i honestly can't tell a difference in the smell. i've had a few completely catless cars in the past and they did have the sulfer-esque exhaust smells. the secondary cats in the n54 midpipes make a difference. overall, i don't think catted aftermarket downpipes are worth the price, pain-in-the butt install, etc. either go catless dp's or stay on the stock dp's

[FDfranklin]

How bad is a few runs on the dyno for the car? I would assume no worse than doing a few 3rd gear pulls on the street, right?

[bryce]

Originally Posted by FDfranklin

How bad is a few runs on the dyno for the car? I would assume no worse than doing a few 3rd gear pulls on the street, right?

it can be a little harder on the engine, since most dyno shops don't have fans that replicate real work wind restistance, cooling, etc. n54's and probably n55's are very strong, however, and there is plenty of evidence that dyno testing the car has little adverse effect

(if you're overly cautious, just bring a spray bottle with water and spray down the intercooler, intake manifold, etc between runs)

[The1]

Originally Posted by bryce

it can be a little harder on the engine, since most dyno shops don't have fans that replicate real work wind restistance, cooling, etc. n54's and probably n55's are very strong, however, and there is plenty of evidence that dyno testing the car has little adverse effect

(if you're overly cautious, just bring a spray bottle with water and spray down the intercooler, intake manifold, etc between runs)

or get a BT tool and put the fans on the radiator at max..... then you'll have lots of air flow.