[Turbo Squid]

I'm interested in seeing who and how someone will tackle upgrading the downpipes on the 335, I read that a BMW designer said that one of the problem points of a 335 with more power would be that the DP (downpipe) is more prone to overheating and cracking as a result of the greater heat.

From my experience with a turbo car, having a 3" DP is very beneficial, even if it feeds into a 2.5" system. I'd say the DP is a greater priority worrying who's is bigger.

I'd also be interested in seeing an upgraded TIP (turbo inlet pipe) and LIP (lower-intercooler pipe) from the pictures I saw it looks like the stock ones are pretty nice, doesn't seem like there are any "pancake pipes" like there was on the 1.8T. But it's always nice to get the most that you can out of what you have.

From the pix off the thread: How the N54 works

You can see in this one, that the air traveling to the turboes from the intercooler encounters a hard turn which probably drastically affects the flow of air in the pipe. Now BMW probably did this because of the limit on available space under the hood of the 335. But I haven't seen pictures up close of the engine actually in the car to see how much room there actually is to play with... Theoretically if there was space for a slightly larger pipe with less of an aggressive bend, it would surely free up hidden ponies, allow faster spooling, and improve flow efficiency into the turbo (maybe allowing more boost to be run?).


Another view of the piping. Also when you look at how the pipe hooks up with the intercooler one would think that there could be a better way of doing it? Once again BMW is probably working against available space. But I'm just throwing it out there. You can see the pipe pointed out by #8 is somewhat pancaked...


Now in this picture you can see why the downpipe would have problems overheating... There is an aggressive bend right after the turbo, all that hot gas is slamming against that wall. On top of that it leads almost straight into the cat. converter... I really am no expert but would it be better to position the cats further down along the way?


In this picture I couldn't help but notice how similar the stock DV's on the N54 look just like the Bosch diverters found on 1.8T's (wooooo). Forge Motorsport makes great upgrades that are widely used in the VW/Audi/Porsche community. Just thought someone should look into whether or not they have thought about applications for the N54.


Maybe someone will come out with a silicone hose kit for the turbo piping on the 335. That would be great. I believe Samco makes them for VW/Audi/Porsche.

Haha, I just realized that I haven't fully read that thread on how the N54 works, so I'm guessing that when I come back to my computer later and read it I'm going to have alot of my previously stated ponderings answered.

Just thought I'd kick of a downpipe/LIP/TIP/DV discussion because I haven't seen any good ones so far on here. I'll be doing research about this stuff in my free time.

Please feel free to correct me on anything stated above. I'm in no way a pro/expert on the matter, I just have some experience with turbo cars and thought I came up with some interesting points.

[eriks]

I've been thinking of a few of your points as well. After looking at the downpipes and those pre-cats hanging a few inches off the turbos, I started wondering who's going to the the first company to offer gutted pre-cats? This is a very common mod on B5 S4's. It's a quick way to free up ~10hp and get faster spool times. Plus, you can actually hear the turbos whistle without the pre-cats! It's music to my ears!

It'll take some time for everyone to catch up but I'm sure that some great parts will be out soon.

[herbz]

great post. can you explain which is the downpipe in pictures 1 and 2? i'm having a hard time finding it.

in other communities i know downpipes./uppipes would be a first mod, such as the WRX.

[Turbo Squid]

Originally Posted by herbz

great post. can you explain which is the downpipe in pictures 1 and 2? i'm having a hard time finding it.

in other communities i know downpipes./uppipes would be a first mod, such as the WRX.

No problem the downpipes aren't visible in pic 2, but here they are on pic 1.


The downpipes are the pipes that exit the hot end of the turbo and go through the cat. converters and then onto the rest of the exhaust system until expelled into our wonderful atmosphere.

[Bravo1]

In the pictures the downpipe would start where the wideband o2 sensor is located and go all the way back to the exhaust. It will be interesting to see what some people come up with due to the space limitations, but just removing the cats would free up a good 10 to 15 whp after a tune.

[bnj]

The benefit of larger diameter downpipe would be high as far as the dp diameter is less than turbo outlet diameter. If the turbo outlet diameter is the restricting bottleneck, then the benefit of larger dp diameter is pretty small.

Having small turbos, I guess the turbo outlet is small and larger downpipes will not have big gains.

The later the cats the better so there at least is room for enhancement.

[Turbo Squid]

Ultimately what I'd like to see for the 335 is a turbo back (downpipe+mid-section+rear-section) exhaust system that would free up a lot more horsepower plus allow you to run more boost without worrying about your downpipes cracking.

This sort of system would have to be made using a high-quality stainless steel. With a 3" (or however large a diameter the opening to the exhaust end of the turbo is) downpipe, that feeds on down to a pair of high-flow cat. converters (that still work well enough to help us pass emissions; of course there would be an option for those who don't need that or don't care for it, where the cats would be replaced by test-pipes/straight-pipes. Better yet a system that would allow for cat. converters to be bolted onto the downpipe then bolted to the rest of the system which could be replaced by straight pipes that would just bolt in whenever someone feels like it.)

The system would then feed into either a high-flow resonator (so as not to hinder much performance for those who like to keep it quiet) and finally to a high-flow muffler on the back.

The system would make use of a solenoid that could open and shut the left side of the dual exhaust to aid the car in warming up; just like the stock system does.

The layout would be as such: (component order)
Turbo - Downpipe - Mid-Pipe(choice of bolt-on cat or bolt-on straight pipe) - Rear-Pipe(choice of hi-flo resonator or straight pipe) - Muffler(heck why not a choice of straight pipe again or a high-quality performance muffler.) - Choice of tip (but of course.)

Somewhere in there would be a proper X-pipe I dunno where it should go, but I guess the warm-up solenoid should be somewhere near it too.

I talk too much...

[Bob at Stratmosphere]

Incase you are wondering here are our Hyperboost Valves on our BMW 335i

[Turbo Squid]

Originally Posted by Bob at Stratmosphere

Incase you are wondering here are our Hyperboost Valves on our BMW 335i

Do you offer your Hyperboost Valve in "Stealth black"?

Can you please explain for the people on here what your DV can do for their 335's.

Do you guys make or carry Silicon hose kits? As a replacement to stock turbo piping systems? Would you know who does?

Thanks

[Weedo]

Originally Posted by Bob at Stratmosphere

Incase you are wondering here are our Hyperboost Valves on our BMW 335i

Can't wait to hear what the Milltek sounds like. And along those lines, what kind of power it will produce with an Xede in front of it!

[Dustin Bramell]

Turbo squid asked me to reply to this thread, so here are my thoughts.

Exhaust: Each year, auto manufactures are faced with ever increasing SMOG restrictions, and requirements. Many of these requirements come in the form of cold start emissions. The biggest problem with cold start, is that the catalytic converter is extremely inefficient when it is cold. Because of this, the OEMs are always looking for new ways to heat the cat as quickly as possible. In the past they used smog pumps to pump oxygen into the cat to heat it up. This works, but the heat generated by combustion (exhaust) does a much better job of getting the cat warm. So, as the regulations increased, the amount of heat lost before hitting the cat decreased. This was achieved by simply moving the cat closer to the heat source (the combustion chamber). The problem with this is, that it creates a lot of heat and back pressure right at the combustion chamber, which makes the vehicle more knock prone. So, with that said, there is a fairly good chance that power can be found by moving the cats further downstream, and of course replacing them with high flow cats. How much power is unknown, because the piece looks fairly large, meaning that it could not be a source of large amounts of back pressure.

Diverter valves (BOV): Ideally, you want to run a diverter valve as soft as possible, without the possibility of it leaking. Of course, we are making 11psi on a stock DV, with no signs of leakage, meaning that it is up to the task and doesn't need to be upgraded. Going with a stiffer spring inside the DV will only cause more surging, which is very difficult on your turbos.

Charge piping: The pancake pipe was one of the first thing we looked at. But the more we looked at it, it seemed as though that was a compromise they had to make. If you look at it in the car, you can see that they didn't have much room to work with and that is the solution they came up with. Unfortunately, for now it looks like it has to stay. If it is any conciliation, with the exception of a few projects, we have never found intake piping to be much of a power adder anyways.

[max boost]

Originally Posted by Dustin@Vishnu

Turbo squid asked me to reply to this thread, so here are my thoughts.

Exhaust: Each year, auto manufactures are faced with ever increasing SMOG restrictions, and requirements. Many of these requirements come in the form of cold start emissions. The biggest problem with cold start, is that the catalytic converter is extremely inefficient when it is cold. Because of this, the OEMs are always looking for new ways to heat the cat as quickly as possible. In the past they used smog pumps to pump oxygen into the cat to heat it up. This works, but the heat generated by combustion (exhaust) does a much better job of getting the cat warm. So, as the regulations increased, the amount of heat lost before hitting the cat decreased. This was achieved by simply moving the cat closer to the heat source (the combustion chamber). The problem with this is, that it creates a lot of heat and back pressure right at the combustion chamber, which makes the vehicle more knock prone. So, with that said, there is a fairly good chance that power can be found by moving the cats further downstream, and of course replacing them with high flow cats. How much power is unknown, because the piece looks fairly large, meaning that it could not be a source of large amounts of back pressure.

Diverter valves (BOV): Ideally, you want to run a diverter valve as soft as possible, without the possibility of it leaking. Of course, we are making 11psi on a stock DV, with no signs of leakage, meaning that it is up to the task and doesn't need to be upgraded. Going with a stiffer spring inside the DV will only cause more surging, which is very difficult on your turbos.

Charge piping: The pancake pipe was one of the first thing we looked at. But the more we looked at it, it seemed as though that was a compromise they had to make. If you look at it in the car, you can see that they didn't have much room to work with and that is the solution they came up with. Unfortunately, for now it looks like it has to stay. If it is any conciliation, with the exception of a few projects, we have never found intake piping to be much of a power adder anyways.

GREAT INFO DUSTIN!

here's what i was thinkin' as far as modding the exhuast..//[/IMG].



this way all nice and quiet when wife is around
that and 100 octane and here we go!



BTW ANYONE WANNA SELL STOCK EXHAUST, PRE MUFFLERS ONLY ???

[Turbo Squid]

Originally Posted by Dustin@Vishnu

Turbo squid asked me to reply to this thread, so here are my thoughts.

Exhaust: Each year, auto manufactures are faced with ever increasing SMOG restrictions, and requirements. Many of these requirements come in the form of cold start emissions. The biggest problem with cold start, is that the catalytic converter is extremely inefficient when it is cold. Because of this, the OEMs are always looking for new ways to heat the cat as quickly as possible. In the past they used smog pumps to pump oxygen into the cat to heat it up. This works, but the heat generated by combustion (exhaust) does a much better job of getting the cat warm. So, as the regulations increased, the amount of heat lost before hitting the cat decreased. This was achieved by simply moving the cat closer to the heat source (the combustion chamber). The problem with this is, that it creates a lot of heat and back pressure right at the combustion chamber, which makes the vehicle more knock prone. So, with that said, there is a fairly good chance that power can be found by moving the cats further downstream, and of course replacing them with high flow cats. How much power is unknown, because the piece looks fairly large, meaning that it could not be a source of large amounts of back pressure.

Diverter valves (BOV): Ideally, you want to run a diverter valve as soft as possible, without the possibility of it leaking. Of course, we are making 11psi on a stock DV, with no signs of leakage, meaning that it is up to the task and doesn't need to be upgraded. Going with a stiffer spring inside the DV will only cause more surging, which is very difficult on your turbos.

Charge piping: The pancake pipe was one of the first thing we looked at. But the more we looked at it, it seemed as though that was a compromise they had to make. If you look at it in the car, you can see that they didn't have much room to work with and that is the solution they came up with. Unfortunately, for now it looks like it has to stay. If it is any conciliation, with the exception of a few projects, we have never found intake piping to be much of a power adder anyways.

Great info man, thanks. Yea, I thought the amount of available space would become an issue. Oh well. I'm looking into it with Samco Sport. They make silicon hose kits.

As for the exhaust I'm sure in a short while we'll be seeing turbo-back exhausts for the 335.

The electronic butterfly valve would fix the problem of people that wanna keep quiet at times, but have the power gains of WOPipes.

[NaViT]

this threads actually interesting to read keep on im learning ....

[Turbo Squid]

Well once again I was bored, and let my mind wander and got to thinking...

I was also looking into Polymer gaskets for the intake manifold... I remember this being a really good bang for the buck in the dub-world for those who were confident enough to remove their intake manifold and replace the existing gasket with the high-performance piece. Tests proved that thanks to the gasket, the manifold would stay 30-50° F cooler allowing the air to be 20-30° F cooler.

Here is the website for dubbers:PowerGasket

Now maybe someone could have the 411 on whether or not the N54 already utilizes a high-performance polymer gasket for the intake manifold. I'm sure BMW designers know their stuff, but who knows, there most certainly would be some power gains on top of being better for the engine (Cooler charge air)... And it's a relatively inexpensive mod. Fairly EZ to do for those of you who are mechanically inclined. I'm just trying to think of the little things people could do for their 335's to help them out.

Ok well I'm going to run off and conjur up some more random ideas for how I think I could do a better job at engineering the 335 than BMW can.

[Turbo Squid]

I just did a search to see who else does Gaskets. I found what looks like the "Engineering Search Engine"... Global Spec

http://gaskets.globalspec.com/Indust..._gasket_vortec

I don't have the time to register or whatever, just thought I'd put it out there for those of you who are as curious as I am and would like to spend some time to figuring this stuff out.

[Jonn335]

given the lack of space for the downpipes, it might be beneficial to join them together sooner, to allow for a bigger pipe size (one 3" pipe flows the same as two 2.1" pipes). I bet you could squeze a 3" pipe in there, with maby a 6" double section out of the turbos to mount the 2 oxegen sensors, and allow the engine managment to 'see' the mixture from it 2 banks, and allow it to do its magic. of course the cats would need to go, or be mounted further down the system after it's split again. Obviously the cold running emmissions will be worse, but this is a small price to pay for more power.
The intercooler pipework is all a bit restrictive looking, but it doesn't look like there ia any more space, so it will have to do. I am sure that a more efficient intercooler could be fitted in the same space tho, with bigger end chambers, and a more efficient core. Alternativley, there is the option of fitting a full size intercooler in front of the radiator.
One think which has me thinking, is the direct injection. From what i have read about it it should allow the engine to run more eficiently, and give more power. The stock output of arround 100HP/l is nothing special for a turbo engine, so large gains should not be dificult, ie should be easyer than with conventional injection. (part of the thinking behind direct injection is to discourage detonation and eliminate pre-ignition (how can the fuel pre-ignite if it isnt there!)
with a bigger intercooler, good exhaust system and a nice fuel i think we can see 380 or more whp. I also would expect the stock fuel system to be at its limit at that power level. Any more power will probably need another set of injectors. Luckily the xede can handle that as well.

[Turbo Squid]

See I'm thinking that for such tiny turbos and low boost, the stock intercooler. Being a decent sized front mount intercooler, is probably sufficient and could even hold up to the flow demands of more boost. But I'm sure the piping can be very much improved.

I also saw that tuners such as Discovery Automotive use Water/Methanol Injection systems with their BMW's and get great results.

Aquamist


I also found this brand Devil's Own Injection

Kits from them usually run around $300. But I think I would trust Aquamist more...

These systems yield great power gains, as well as being really good on the motor. Does anyone have any experience with Water/Alcohol Injection?

[Jonn335]

given the high C/R of this engine water and /or methanol injection sounds like a really good idea, and may bemore cost effective than trying to change any of the physical intake system.

[all8up]

Originally Posted by Jonn335

given the high C/R of this engine water and /or methanol injection sounds like a really good idea, and may bemore cost effective than trying to change any of the physical intake system.

Here's a posting from my old car community...
http://forums.nasioc.com/forums/showthread.php?t=937176

Nice thing the Xede does have a solenoid that can activate alch/h20 injection...

[Turbo Squid]

Originally Posted by all8up

Here's a posting from my old car community...
http://forums.nasioc.com/forums/showthread.php?t=937176

Nice thing the Xede does have a solenoid that can activate alch/h20 injection...

Well there we go, we should talk to Shiv and see if Vishnu can incorporate a H20/Alcho injection system into their Xede (make it an option) with an unit and interface from AquaMist.

Shiv care to comment?

[NaViT]

Shivs down here in South Florida i think tuning some 335s