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Old 12-03-2010, 04:15 PM
robertobaggio20 robertobaggio20 is offline
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Cold Air Intake modification

1. This justifies its own thread for focused discussion, so I've moved it over from the angel eyes thread where it was originally.

2. I have a potentially radical suggestion that I've checked out and have confirmed to be conceptually doable. The big picture would be to remove the driver's side high beam headlamp and allow air to flow directly into the airbox, while modifying the low beam controls and bulbs to enable dual low/high beam functionality for the low beam lamps. The following applies to a 525 with an m50 and m20 engine. Not sure about other cars. Details follow.

3. We have a terrible stock air intake at the end of the air box. Shine a flashlight on the outside inwards and you can't see anything through the airbox area (first, remove the headlight panels). However, you might notice that the stock airbox's inlet is almost exactly in front of the driver's side high beam headlight.

So....

4A. Remove either the driver's side or both driver's and passenger's high beam headlamps. [ Have not decided if it would look alright with just one out. ]

4B. EITHER Fit a kind of circular porous plastic or metallic mesh cover over where the headlight used to be. Some track M3s and M5s have something similar to this. Make sure its a conservative colour or a colour that works with your car's paint. Purely as an example to illustrate, remember the wire mesh that's on both ends of the air mass sensor? Imagine something like that, but bulging out to match the headlight's shape, and appropriately coloured to either match the car or look sporty without being garish. Best not to leave a gaping hole there.

OR

4B2. Create an electrically operated movable custom vane setup that's either (1) spliced with the speedometer's wiring or (2) controllable by dials or switches separately installed in the cabin/dovetailed with existing switches stealthily such as the fog lamp's switch, that can be adjusted to open and close in varying degrees automatically or via the manual cabin switch, according to your forward airspeed. LOLOL

4C. The mesh will be opaque to casual observers, make your CAI stealthy, and keep snakes out. lolol. It will also pretty much make it a direct cold air intake for your car. Fit a custom plastic channel tube etc between the back of the porous mesh and the front protusion of your airbox, and you've got 'ramjet' possibilities there dude. Remove the vortex/ venturi vanes at the airbox's inlet, they are pointless if the swirling air immediately hits an air filter, and they cause an obstruction as well.

4D. Best to set it up such that the alternator's cold air intake is securely filtered via a very light gauzed cotton implement. Alternatively, a similar wire or plastic mesh can be placed of the the alternator's air intake channel to keep out the larger particles (this is probably more maintenance free). Of course, the increased cooling overall from this modification will extend the life of your alternator, which is nice.

4E. Get HID bulbs and ballasts for both low beam lights.

4F. Rig it up with modifications such that its the low beams that would suddenly switch to brighter high beams when you flash or activate your usual high beam lever. This is electrically possible, but only with HID lights apparently as they can have two different brightnesses, the stock bulbs can't (or so I was told, I have not corroborated this with another electrician).

4G. Following this, start the car and leave it to idle without revving, for between 5-10 minutes to allow the ecu to adapt to the vastly increased airflow. Rev/drive off only after that.

4H. Thus, you'll get a fantastic direct cold air intake without cutting up the engine's floorboard to use a trunk that leads from the driver's foglamp opening to the airbox in the engine bay, you'll save on the expense of purchasing a pod airbox OR really boost its effectiveness if you already have one, you'll still have both low and high beam functionality perfectly, the E34's perennially poor headlight problem would be fixed, you don't have to sacrifice your fog lamps, and the car should look very cool from the front, this is safer than driving without an air filter, your alternator should last longer due to better cooling, and even if you have to pay someone else to do this, the labour charges should not exceed 1 hour as the bumper need not be removed (only the front grill assembly, warn them to be carefull as they do this as the clips holding the grills and the headlights are fragile by now and break pretty easily - best to have a few standing by just in case). In fact, you'll be saving some money somewhere as the labour charges should be included in the purchase price of the HID lights, and you'll only have to pay for one pair of HID bulbs not two. However, relays etc may cost a little more, and the fuses for the headlights might have to be rerouted somehow (not sure).



Whaddya guys think?


Rgds,
Roberto

p.s. 4I. Dunno if low/high beam functionality can be done with stock bulbs.
p.p.s. 4J. Oh yeah, and screw any error messages that result from this modification lololol.

Last edited by robertobaggio20; 12-03-2010 at 11:25 PM.
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  #2  
Old 12-03-2010, 06:59 PM
SawheadE34 SawheadE34 is offline
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Sounds like it would help. Sounds similar to the RPI intake my buddy has on his E60 M5. they help out at higher speeds but at low speeds there's not much of an increase. I understand the ram air design and it works with the stock box considering you wont heat soak as you would with all the low quality intakes I've seen for the 525s and such. But along with that you would want a better flowing air filter to help with the gain. As for the high/low beam concern, im not sure you can do it with the low beam head light. it doesnt have the right wiring set up to use a high/low beam HID kit. You will have to do a bit of wiring to make that possible but as long as you can understand a simple wiring diagram im sure you can make it work.
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Old 12-03-2010, 07:26 PM
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Roberto, you are definitely an innovator and progressive thinker. As to the lights, I havenít a clue Electronics and I donít play well together.

One of my main concerns in your ram air design is the possibility of hitting a pot hole (or other low lying area) filled with water and then suddenly ingesting a large amount of the water into the intake manifold. This can cause hydrolock with resulting catastrophic failure and destruction of the engine. There is a link on the E39 forum where a guy had this happen with his 540. He has some impressive pictures of the hole in the block and various sundry of destroyed parts.

Here's one link:

https://www.bimmerfest.com/forums/sho...ighlight=hydro

I'm going to try to find the other.

Also, I donít think that the engine truly gains HP unless the exhaust is also modified to allow for better flow of the exhaust gasses.

Just my thoughts (for what they are worth),
Steve
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Steve

Calypso Red 1992 525i - Sold

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold


Last edited by BMR_LVR; 12-03-2010 at 07:29 PM.
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Old 12-03-2010, 08:58 PM
wisbimmer20 wisbimmer20 is offline
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Robertos innovations are indeed impressive.
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Old 12-03-2010, 11:18 PM
robertobaggio20 robertobaggio20 is offline
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Thank you wisbimmer20 and bmwlvr. Yes, this is another one of my observations......which I'm sure no one else will try, just like the reduced fuel pressure regulator.

Bmwlvr sir, I read through that E39 thread. Indeed hydrolocking is a problem sometimes, even when there's an absorbent air filter in the way and an engine that can safely ingest a certain amount of water (have done water decarbonisation several times before, 2 gallons at a time, no problems.) However, if you read further, you'll come to a post by the OP that says his CAI was located in the bumper. The method suggested in this thread locates the CAI more directly, and much higher at the grills. Thus, the risk of hydrolocking is nearly eliminated (or at least, becomes equivalent to the current stock arrangement) as that portion of the car is unlikely to be under water at any time unlike a bumper navigating through a flood. You wouldn't be driving the car if the bonnet was under water. You wouldn't be driving the car even if the bumper was under water.

Apart from that, driving the car fast in pouring rain will also not be a problem because, as I've mentioned, I've done alot of water decarbonising on my engine before, 2 gallons at a time, and that was through the brake booster's vacuum fitting, without an intervening air filter. No problem to the engine, you just get alot of fog coming out of your tailpipe, and some water vapour makes its way past the CC rings into the crankcase turning your engine oil slightly milky, and that clears up after 15-30 minutes of driving as the hot oil causes water to vaporise which gets expelled through the crankcase ventilation system, thus cleaning the oil.

In any case, if one were to place a circular fine mesh element where the driver's high beam headlamp used to be, large rain droplets will generally splatter against this and break up into more manageable water vapour particles that are broken up even further once they encounter the air filter.

Quote:
Originally Posted by BMR_LVR View Post

Also, I donít think that the engine truly gains HP unless the exhaust is also modified to allow for better flow of the exhaust gasses.
Sir, please watch this space.

Last edited by robertobaggio20; 12-04-2010 at 01:31 AM.
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Old 12-04-2010, 07:42 AM
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Quote:
Originally Posted by robertobaggio20 View Post
Sir, please watch this space.
I presume there is more to come on the exhaust ?
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It's Deja Poo - as in, I've heard this **** before.
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Calypso Red 1992 525i - Sold

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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Old 12-04-2010, 09:42 PM
wisbimmer20 wisbimmer20 is offline
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haha nice popcorn emoticon, that's fantastic. it's nice to have existential conversations like this on here beside simply moaning about our cars problems.
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Old 12-04-2010, 10:36 PM
robertobaggio20 robertobaggio20 is offline
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Never thought about it bmwlvr, but now that you've thrown down the bratwurst, I have an idea. In fact, I have three. No, I have 4. Actually, there's a fifth one too. And now a sixth.


1. Higher CC temperatures

If you run the car lean, the temperatures within the combustion chamber (cc) will be much higher. This should mean that they would exit the cc much faster. Is there a way to do this without chipping the car?

2. Redesign exhaust valves

On top of that, it seems possible that the exhaust valves are poorly designed. All the valves, both intake and exhaust, are shaped like the end of a trumpet. On the intake side, this helps to disturb the incoming fuel-air mixture and generate turbulence and swirl in the cc (combustion chamber) as it is forced to swerve over the bell shaped end of the valve, thus promoting thorough mixing of the mixture and therefore better combustion. However, the exhaust valve serves no useful purpose in being so shaped. The large bell shaped flat head presents an obstruction to exiting gases, which now need to flow around the bell shape to get to the exhaust port, instead of leaving directly. Swirling the exhaust gases has no benefit to the car that isn't already taken care of by the catalytic convertor (in terms of emissions).


3. Exhaust Vacuum generation.

If we can somehow create an instantaneous, collapsible and enduring vacuum right behind each exhaust port just as its about to open to expel exhaust gases, we would create an additional force via the vacuum's suction effect to the gases, thus causing them gases to get the hell out of the cc faster.

One way to do this would be to create a small square chamber (lets call this the vacuum port) right after each exhaust port, with a ferris-wheel type continuously rotating vane within it connected to the pistons or the crankshaft. The vane within the chamber would move from point a (nearest to the exhaust port) to point b (some distance away), when the exhaust valve is closed. Since there's no air while this happens, a vacuum is created. At that point, the exhaust valve opens and the exhaust gases rush out. A split second later (NOT simultaneously), the ferris wheel type vane system uncovers the opening to the rest of the exhaust manifold at the end of the vacuum port, thus allowing the gases to flow right through without gases in the manifold flowing back in. The ports close and the process repeats itself. All this has to be timed well and might have to be slaved to either the pistons or the exhaust cams. We must also ensure that the additional weight and mechanical inertia created by this apparatus does not eliminate or even reverse the gains created by vacuum exhaust porting. )


4. Exhaust manifold redesign

It is possible to redesign the pipes comprising the exhaust manifold into a bell or megaphone shape, such that as gas moves through the megaphone, it loses pressure as the same amount of gas is now occupying more physical space. Gases move from a region of high pressure/high temperature to a region of lower pressure/lower temperature [ I hope I've got my physics right here ]. So, this should create an additional force that pulls the cc gases out.

This is not a new idea. The problem with it though is that pressure waves get created by successive pressure fronts along the megaphone channel. These pressure waves travel up the megaphone right to the engine and equalise the pressure for exiting gases. Careful experimentation is required to ensure that these back pressure waves do not undo all the good that was done. However, the negative pressure people appear to have solved this problem. Google them...highly interesting read.

5. Cooler exhaust manifold.

Everyone knows that the cooler the exhaust manifold, the lower the pressure of gases there, which increases the pressure gradient between the combustion chamber and the exhaust manifold, which creates more of a force expelling gases out, which creates more HP according to mr bent lee.

Earlier on in this thread, I suggested a direct cold air intake design with good ramjet potentials. The amount of cold air flowing into the engine will increase as the car's speed increases. Air has another useful property....it cools hot things down, which is why the radiator for all cars is right out in front.

We can create similar air channels....oh yes.....possible brainwave (small one though, well get to it in a minute).
...as I was saying, we can create similar channels using custom metallic tubing leading from the front grill area of the car or the lower bumper portion of the car, all the way to the exhaust manifold. Instead of custom tubing, it may be cheaper and easier to use large flexible steel lined hoses.

Here's the idea. The driver's side high beam headlamp can be removed and used as a cold air intake for the engine. The corresponding right high beam headlamp? That can be removed....and used to channel cold air through the car, onto the exhaust manifold. This would be for the m50 cars.

The only caveat would be to try to ensure that six separate output channels are created to direct six separate cold air streams onto the exhaust manifold's six separate pipes. If the tubing is merely directed at the first exhaust pipe nearest to the front of the car, the air reaching the last pipe would be heated up by the preceding six, and each successive pipe from the 2nd to the 6th would get differential cooling, which is probably not the best thing to go for.

The output tubing needs to be angled downwards, so that cooled air naturally flows and joins the airstream under the car as it passes over the hot exhaust manifold pipes, thus reducing in-car turbulence. lolololol !

What's great about this is that when the car is travelling fast, the engine would be generating more heat due to higher rpms. However, since there's more cold air coming in due to the higher forward airspeed, you get better cooling as well. So, it works itself out.

The passenger's headlamp area, now functioning as an exhaust cooling inlet, needs to be protected by a grill to keep out stone chips and to look consistent with the driver's headlamp cover. Rainwater going in will eventually hit the exhaust manifold and merely vaporise, providing extra cooling. The hot iron exhaust pipes will not crack when water hits it, I've washed my engine bay many times with a huge stream of cold water, there's a big steam show and lots of fizz but nothing beyond that.

6. I've forgotten the 6th idea. It was probably a really wacky one anyway just for the hell of it.

Perhaps I should move this comment to its own thread. Lol. Anyway, these ideas may not lead to many benefits at all. And I wouldn't be surprised if they are all reinventions of the wheel.

I myself was thinking of wrapping the exhaust manifold in a heat wrap to keep the heat out of the engine bay. Now am wondering if, in preventing cooling there by keeping the heat in using the ceramic heat wrap, would I end up sacrificing horsepower?

Last edited by robertobaggio20; 12-05-2010 at 03:40 AM.
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Old 12-05-2010, 08:45 AM
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BMR_LVR BMR_LVR is offline
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1.

2.

3.

4.

5.

6. (probably, if you could remember the idea that is )

The idea of wrapping the exhaust has been shown to increase HP a little I do believe. It certainly will keep under hood temps down too.

By the way, did you happen to be enjoying any ETOH at the time you authored this dissertation ?
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Most problems are usually something simple !

Quote:
Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i - Sold

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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Old 12-05-2010, 09:13 AM
robertobaggio20 robertobaggio20 is offline
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No sir, I wasn't drunk when I wrote that. They couldn't be that bad ! lolol

Please re-read them a second time, if I may strain courtesy. I read them again, and feel the idea with the best potential would be the redesign of the exhaust valve. Currently, the flared exhaust valve has is being pushed into the cc as the piston pushes the exhaust out. It not only goes against the direction of flow of the gases, it (as was explained above) presents a large flat face that the exhaust gases would have to work around to get through to the exhaust port being uncovered by the exhaust valve. So its an obstruction in two senses. Naturally, we can't get complete venting as a result.

Imagine if, instead of an exhaust valve that uncovers the exhaust port by being pushed into the chamber, we had one that was [I]pulled up[I] to uncover the same and pushed back/allowed to fall back once that cycle was finished. Or we had an exhaust valve which was pushed to the left/right to uncover the port and allowed to move back thereafter.

Essentially, these two methods are aimed at reducing the obstruction posed by the object that covers the exhaust port's gap while the engine is not in its exhaust cycle. That object is currently the exhaust valve. Change the way that works, and you'll end up with a better venting mechanism and couple of more horses.

Any thoughts?


rgds,
Roberto

p.s. Thank you for the comment on wrapping my exhaust headers, I think i shall proceed as you recommend. I need to rethink the science around this more.
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