My Custom CAI - '93 525i m50 Vanos

[ericcamaro]

I made this kit for pretty cheap and it seems to work very well. I am very happy with the performance increase not to mention the engine now roars, sounds like a 2.5 porsche carrera to me. (If youve ever heard one of those before. they sound gooood.) All that it took to put this kit together was few pieces off Flea Bay.
1x 45* bend 3" diameter stainless or aluminum pipe
1x 9" straight 3" diameter pipe
2x 3" silicone hose clamps
1x Filter your choice I went with the weapon R foam filter with the built in velocity stack as well as a place on the front of the filter to hook up a ram air tube.

All you do is rip out that old airbox and attach the system straight onto the MAF the front piece of plastic that hangs down right behind the headlights will have to be modified to allow the new filter through. BTW I also coated my pipes in some roll on truck bed liner (gives a nice rubberized, relatively stock looking appearance.) let me know what you think positive or negative.

[Rustam]

let me know what you think positive or negative.

Well, cold air intake usually has a shiny reflective pipe to reflect heat and not allow the pipe to heat up. In essence all you've done is changed the filter. You may want to swath the intake now all the way from the filter with fiberglass or exhaust wrap to keep it from getting warm - then it would be true cold air intake. I personally see no advantage in doing this nor in what you have already done, since the intake is cold enough already because it is on the otehr side from the exhaust.

I would see an advantage in doing this if it helped you carry the intake outside for ram-air effect...

However - it does look very neat.

[BigKriss]

Like Rastum says, there is no heat shield. So your getting an increase of hot air entering the engine which decreases performance. This upgrade is negative. I don't like your hot air intake at all. You then talk about a performance increase, how much performance increase did you get and how is it better? I doubt the filter is better performing in terms of stopping small particles entering the engine also - thats a double wammy. This mod is gay. I used the stock air box with a duct coming from outside the engine bay, I couldn't notice any difference in power/throttle response or induction 'roar'. I fail to see how your setup is superior.

[ericcamaro]

You are right there is no heat shield but you are wrong about the filter a good foam filter flows better than a K&N and filters better than the stock paper filter. And oddly ther was a noticeable power increase. And everyone knows that there are built in sound baffles in a stock airbox so you will never hear it with your stock air box hooked up. And lastly if you were to notice ther is quite a layer of truck bed liner on the pipe which not only makes it look good but insulates the pipe very well, making the air plenty cold entering the engine. I also increased about 3 MPG highway when switching to this setup so Big Kriss I think its time for you to change your name to BIG GAY KRISS. Because you have no Idea what your talking about.


Like Rastum says, there is no heat shield. So your getting an increase of hot air entering the engine which decreases performance. This upgrade is negative. I don't like your hot air intake at all. You then talk about a performance increase, how much performance increase did you get and how is it better? I doubt the filter is better performing in terms of stopping small particles entering the engine also - thats a double wammy. This mod is gay. I used the stock air box with a duct coming from outside the engine bay, I couldn't notice any difference in power/throttle response or induction 'roar'. I fail to see how your setup is superior.

[BigKriss]

LOL - I must have got you so angry that you’re attacking me personally.

Why do you think the stock air filter is a restriction on the engine? One is your argument that the filter flows more CFM and filters better than a stock paper filter at the same time? Show me some references to tests were they say this is true. I can give you two sources that counter what you are saying;

http://www.bmwe34.net/E34main/Upgrade/Air_filter.htm
http://home.usadatanet.net/~jbplock/ISO5011/SPICER.htm

You say there was a noticeable power increase, how much do you estimate and what acceleration time improvements (using a stopwatch) did you notice?

Then you go onto say that because you have insulated the intake pipe with truck bed liner that the hot air you are sucking from underneath the engine bay now makes "the air plenty cold entering the engine", this was surely your best line.

To sum it up. Your weapon R foam filter;
- flows better and filters better than a stock filter
- improves power noticeably and;
- improves fuel consumption by 3 MPG

All the other members on here running a stock filter setup (which are the majority) have no idea what they are talking about also! - Sarcasm intended.


You are right there is no heat shield but you are wrong about the filter a good foam filter flows better than a K&N and filters better than the stock paper filter. And oddly ther was a noticeable power increase. And everyone knows that there are built in sound baffles in a stock airbox so you will never hear it with your stock air box hooked up. And lastly if you were to notice ther is quite a layer of truck bed liner on the pipe which not only makes it look good but insulates the pipe very well, making the air plenty cold entering the engine. I also increased about 3 MPG highway when switching to this setup so Big Kriss I think its time for you to change your name to BIG GAY KRISS. Because you have no Idea what your talking about.

[emw525E34]

Now now, lets not start the name calling, shall we?.

I have done extensive testing with twin digital temps. Heat soak is a problem but only on a hot day and if you are idling in traffic often. If you cruise more so than idle, heat shield does not make much difference.
My measurements say with headtshield, heat soak is gone within 2 mins from a stoplight /idle. Without a heat shield, it take 4-5 mins of cruising to clear this soak. So if you journey is within 5 min stoplight intervals, a car without heat shield will lose 10-15 HP due to heat soak.

When it comes to intake sound, yeah, Cone filter gives that great induction noise. But power really does not come on until fairly high RPMs > 4K and when you engine is modified with heatjob, headers, catback etc. Hard to measure this but butt-dyno says some improvement. Maybe the noise may distract but I don't have concrete figures. Mid-range torque seems stronger than stock. That helps with fuel consumption. Or was it a change in driving habit due to this change ?.
I think the work is done fairly nicely. Not quite stock looking. Anything thing with double clamps cannot be considered stock. But good strengthening. Remember to clean that foam often!. It junks up pretty bad over time. Enjoy it, you did that yourself and its certainly different. To some people, thats enough....

[genphreak]

Kriss-O!!!!

What's chewin u up tonight?

Eric... dude don't stress over the comments.

It looks pretty schmick to me. Problem is (as we have all discussed ad-nauseum in many (even heated and otherwise rather technical) debates, the stock BMW airbox is a somewhat well designed unit, so beating it is damned hard.

Tests in this field have (mostly) not been unbiased, and if foam airfilters were better I am sure you'd agree that people like BMW would be using them by now (and if not, first- before any car modders got hold of such 'innovations' and decided they sounded like a good idea). And let's face it, they do sound like a good idea... cleanable, cool-looking and they help the ears on the butt-dyno know what is going in up-front.

I am not against them (though they have been discredited as allowing dust into an engine), I just think the only reason to get one is the sound! Yours does look like one of the best I've seen without a fully sealed cold air box (to heat up in traffic as suggested by emw before this post)

:) nick

[Russell]

Filter surface area would seem to be much smaller.

Be interesting to add reflective foil and insulation like Reflex(sp?) (thin foil sandwich of materials duct insulation) to see if cold air flow, especially in stop and go situations is enhanced.

Just my observation.

[Rustam]

I also increased about 3 MPG highway when switching to this setup

If you have increased 3MPG this is already a suggestion that the filter you've put in is less restrictive than stock filter - more air is allowed into the engine.

A difference in filter may be only along the restriction spectrum from no restriction at all to full restriction. So if a filter "adds power" then you can be very sure that it is less restrictive. There is simply no other reason why a filter can add power.

You cannot expect to just elongate the intake pipe and have it provide you with cold(er) air unless the filter is ducted outside. And if you are willing to argue that the black paint makes good heat shield - no - black matter heats up faster and makes virtually no barrier to heat transfer. It is exactly why we see shiny pipes that reflect light being used for cold air intakes. Conversely, it is exaclty why we see a black radiator, and should stay from aluminum radiators.
______

For the sake of fairness I must say that it may be concievable that you get some cold air from the front being sucked through around the panels, and lights so it may have some minor effect of ram air.

[ericcamaro]

Rustram- its not paint but a thick rubberized coating up to 1/4 in. in places. And the fact it is black is not hurting it much. And I do a lot of cruising and very little in town driving. I am contimplating cutting a whole right under where the stock box was and having the filter mount out of the engine bay. this would take car of all the problems no??

[Rustam]

Rustram- its not paint but a thick rubberized coating up to 1/4 in. in places. And the fact it is black is not hurting it much. And I do a lot of cruising and very little in town driving. I am contimplating cutting a whole right under where the stock box was and having the filter mount out of the engine bay. this would take car of all the problems no??

I am not sure of the construction and placement of air filter box in your car. Can you take more detailed pictures of the area?

Drawing the air from outside the engine bay is the principle of cold air intake.

[BigKriss]

True and without a heat shield your losing power from the hot air from the engine bay. Eric are you going to answer my questions?


Drawing the air from outside the engine bay is the principle of cold air intake.

[Rustam]

Rustram- its not paint but a thick rubberized coating up to 1/4 in. in places. And the fact it is black is not hurting it much. And I do a lot of cruising and very little in town driving. I am contimplating cutting a whole right under where the stock box was and having the filter mount out of the engine bay. this would take car of all the problems no??

You have to swath the line with exhaust wrap all the way to the intake manifold, and make sure that the filter is not allowed to draw air from the engine bay. I am posting second reply to your comment because the first one has been used to comment and I dont want to edit. But the point of this reply is in reiteration about wrapping the line.