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

[bryce]

Originally Posted by mineo77

A sweet Quad exhaust with iCarbon diffuser may be coming out soon for our cars...mid jan/feb...fyi.....;-)

[FDfranklin]

Originally Posted by bryce

lol i'm still running the stock exhaust w/ downpipes. the n55 doesn't have secondary cats, just a cat in the downpipe. so, either exhaust would work in regards to your dealership. i've heard the berk muffler delete in person (friend has one on his 135i) and it sounds AMAZING! it's loud as hell though, so be warned. since you're going to be on teh stock downpipe for a while, the muffler delete might not be a bad way to go

Nothing could be louder than my rx7 so im sure it wouldn't be too loud lol

So the only cat on the n55 is in the downpipe? I swear this is the last of my exhaust questions!

[bryce]

Originally Posted by FDfranklin

Nothing could be louder than my rx7 so im sure it wouldn't be too loud lol

So the only cat on the n55 is in the downpipe? I swear this is the last of my exhaust questions!

no worries, that's why i created this thread




and yes, the n55 only has a cat in the downpipe. you can verify this by looking under your car and then under an n54 equipped 135i. the n54 has two secondary cat's on the midpipes, while the n55 just has a resonator in the midpipes (no cats)

[FDfranklin]

Originally Posted by bryce

no worries, that's why i created this thread




and yes, the n55 only has a cat in the downpipe. you can verify this by looking under your car and then under an n54 equipped 135i. the n54 has two secondary cat's on the midpipes, while the n55 just has a resonator in the midpipes (no cats)

Probably going to order the race one soon!

[Juicehead]

What is the safest maximum whp/tq number without a bottom end rebuild?

With say, strictly bolt-ons & a tune

[mineo77]

[QUOTE=Juicehead;8534075]What is the safest maximum whp/tq number without a bottom end rebuild?

With say, strictly bolt-ons

[bryce]

Originally Posted by Juicehead

What is the safest maximum whp/tq number without a bottom end rebuild?

With say, strictly bolt-ons & a tune

400whp/wtq is "safe," as we haven't had any motor failures from people running the stock bottom end with bolt-ons and tune only. meth is safe, if used properly, but the few motors that have popped were running aggressive meth setups and limited failsafes.


i personally have most bolt-ons, no meth yet, and i'd estimate i'm in the 375-400 whp level. car pulls very strong, no issues *yet*, even the stock clutch has been holding well for 10k miles or so

[bryce]

Originally Posted by FDfranklin

Probably going to order the race one soon!

you'll LOVE it! i sometimes wait to leave until my friend drives off in his 135i to hear the exhaust note

[bryce]

keep it on top! let's limit the amount of repetitive questions in threads by combining those into this thread

[TZANIDO777]

Originally Posted by bryce

it's not that popular of midpipes, but from the looks of it it'll probably be a little louder than say berk or cp-e (resonated). the icarbon midpipes don't appear to have resonators.

would the berk muffler delete and midpipes be worth it? i want a loud and nice sounding system nothing ricey

[mke135i]

Got one for you.. I haven't seen anyone running Nitrous to cool off the IC. Is this not a valid solution anymore? I would think the IC would run much cooler temps and higher traps/boost could be achieved, while still be very engine safe

[The1]

you could do it. however, it becomes a risk. As far as canada goes, any nitrous in a vehicle is illegal here, and people have been doing pretty well about getting rid of it.

At the same time, when these laws passed, Methanol started becoming popular.

I think it's pretty much the same deal in the states.

but if you got some small nitrogen canisters and rigged a paint gun trigger type system for sustained but small bursts you should see some gains.

you can do the same with C02 but, you will start seeing accelerated rusting in areas

My solution, find a junked STi, grab the water bottle from the trunk and the sprayers from the intercooler. then just pour a bunch of rubbing alcohol in the bottle.

[bryce]

^thanks, The1


nitrous is not as consistent to use on the exterior of the intercooler. i'd much rather run a larger aftermarket FMIC with the possibility of meth injection than spray nitrous on the fins of the outside of an intercooler

[bryce]

Originally Posted by TZANIDO777

would the berk muffler delete and midpipes be worth it? i want a loud and nice sounding system nothing ricey

it may be too loud for you, honestly. the one berk muffler delete section i've heard in person is fully catless (2.5" catless dp's). it SCREAMED but sounded pretty sick IMHO. if you're going to run the stock catted downpipe(s), it might not be a bad idea

[The1]

For anyone curious, Catalytic converters and resonators make a huge difference!!!

Cats will steal volume,

Resonators will control the sound, and to a limited extent the volume... but it will primarily get rid of raspyness and weird other tones, making just one sweet sound. So, if you're a pure performance person, go resonatorless, if you like performance and a great sound, get one with a resonator.

If you want pure volume, resonatorless, catless, and mufflerless.

[bryce]

Originally Posted by The1

For anyone curious, Catalytic converters and resonators make a huge difference!!!

Cats will steal volume,

Resonators will control the sound, and to a limited extent the volume... but it will primarily get rid of raspyness and weird other tones, making just one sweet sound. So, if you're a pure performance person, go resonatorless, if you like performance and a great sound, get one with a resonator.

If you want pure volume, resonatorless, catless, and mufflerless.

this is why i'm still considering changing my catless AR dp's to resonated dp's

[The1]

you still running your rear resonator and midpipe with cats?

[bryce]

Originally Posted by The1

you still running your rear resonator and midpipe with cats?

yea, stock midpipes and axle back. i like the subtle exhaust note the stock pieces have and i'm still waiting to see what HPF develops

[The1]

I'd love to find something like a Borla Hush, or that one Silent choice, but i don't remember who makes that.

but a proper cat back system with only a meatier tone, but not much volume above stock.

I'm a sleeper kind of guy.

[bryce]

Originally Posted by The1

I'd love to find something like a Borla Hush, or that one Silent choice, but i don't remember who makes that.

but a proper cat back system with only a meatier tone, but not much volume above stock.

I'm a sleeper kind of guy.

same here

[TZANIDO777]

Originally Posted by bryce

it may be too loud for you, honestly. the one berk muffler delete section i've heard in person is fully catless (2.5" catless dp's). it SCREAMED but sounded pretty sick IMHO. if you're going to run the stock catted downpipe(s), it might not be a bad idea

If you had to pick between the meisterschaft or the berk muffler delete with the berk midpipes, sound wise, which would you pick?

[BMW86]

Originally Posted by TZANIDO777

If you had to pick between the meisterschaft or the berk muffler delete with the berk midpipes, sound wise, which would you pick?

I'd go with meisterschaft.