gentlemen (and ladies)
In my quest for speed, the option of turbo has come up plenty of times. Although with a grandma for an engine, I have stayed away from blowers and looked for hopes and dreams of rebuidling and all motor (and relatively new) heart of the 92 gsr, with the ever so blacksheep, b17.

Now, I try to rob every little horsepower I can from stupid little stuff like this, and I dont care if you dont think it does anything, or if it looks ghetto as hell, I like to tackle tasks such as these, and I enjoy making my own parts. Read on if you care to englightened by such DIY ethics and enjoy a good project.

A while ago I was running a 2.5 cold air intake. I wondered why the 3" wasn't offered for my car, so I decided to build my own. I relocated the battery to the back to give me a little more room while playing in the engine bay. I bought a piece of 3" mandrel bent piping, 3" filter, and used an old connector and rigged up my own 3" cai. Now... I coudln't get the bends quite right so the pipes didn't lineup as good as I wanted them too. the 3" definately pulled harder than the 2.5" cai. Now...as I high end horsepower freak (yes hence me driving a honda) I did my research and found that short rams produce more high end horsepower, because of the whole physics aspect of air velocity. The 3" short ram pulled MUCH stronger than the 3" cai. At nite the thing pulled like a mother, but during the daytime, it seemed that the car after 10 mins of driving would be sluggish because the engine bay would basically be heat soaked. In my quest for cold air but with a short ram, i looked into the ram effect...

heres where it gets fun.

of course i started off going to home depot, lowes, etc. to find funnel type devices with flexible yet sturdy piping. the first time i constructed it, I used bendable aluminun ducting. looked decent and held up great until i put the bumper on, then the bumper support crushed it...not good.

i gave up on the idea and started to dig a little more. I eventually found these, NACA ducts...Used for brake ducts.


(sorry for the crappy pictures)

for $20 shipped, I just couldn't resist. I ordered black..i got clear...turns out i like the clear a little better--I then began to look for some type of ducting...something strong enough to withstand pressure, yet something still flexible. After hours and hours of calling and driving around, i eventually found an inexpensive alternative to the neopreme 300 degree resistant ducting that most stores offer (at $50 per 10 feet....)

3" drainage ducting. the stuff looked bendable enough, and strong enough, and was relatively inexpensive ($20 for a 100ft role...WAY TOO MUCH...luckily the store had some scraps)




I began to assituate the funnel behind the front grill. Making marks and drilling holes for the zipties (ithought bolts would crack it) to mount the piece onto the grill. I decided to mount it behind the grill to keep anything from going in like a bug or a shoe or something...i dunno...plus you can barely see it like this.



with the bumper off, i tried everything to mount the ducting to the funnel, but when all was said and done, good ol kentucky chrome (duct tape) was the only thing that would hold it on

In order for the ducting to fit, I have to remove / relocate the passenger side horn. I also took a nice little chunk out of the body to allow the pipe to bend more smoothly.

It is run along the inside of the bumper,



around to where the resonator sits, and up through the airbox hole.


(ignore radiator fluid, its leaking...)

the ducting comes up right next to the filter...


this is how she stands...


now some of you are probobly thinking...wouldn't it make more sense to have the ducting go strait into the filter or make a box around it...well that is my next project.


im making a template currently out of a oil box so i can design a heat resistant box to draw the cold air that is being drawn up from the bumper. here is what i have in mind...

this end is for the ducting to come through...


this is to go over the pipe to enclose the filter...



fits over filter / intake as so...



ducting comes through as so...



would fit like so...



and final product looks something as so...



now im sure i could have done this project with a little more efficiency. I could have used something much less resistant, could've drilled a hole in my bumper, could have used a bigger NACA duct, could have cut bumper support / chassis and have tube run up from under headlight, could have put duct in front of grill, but when all is said and done my goal was to have a source of cold air for my short ram and look as discrete as possible.

once i start working on my plastic piece (box) I will post more pics and let you know how it turns out. thanks for reading this monstrosity. peece.


ps...next issue includes...does it work...

pps...race version...(ie ducting right to intake no filter)

 

that can work but there are better methods to it and they will still help, the way i chose to go may help you a bit, hope you kept your stock airbox/etc. here's the link: https://honda-tech.com/zerothread?id=563658

 

yes ive seen that before, but the stock airbox doesn't seem to flow as well as a 3" filter / stick approach. also, my front bumper is a little different, so if i take out the turn signal its gone, AND the HUGE crossmember is right in the way, hence why i didn't run it under the headlight (g2s...look).

 

im 'n it! good job on the ghetto fab!

 

Awesome writeup! Keep us posted on the completed project. I find this very interesting. Looks like you're on the right track. Keep it up!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RedStarGsr &raquo;</TD></TR><TR><TD CLASS="quote">yes ive seen that before, but the stock airbox doesn't seem to flow as well as a 3" filter / stick approach. also, my front bumper is a little different, so if i take out the turn signal its gone, AND the HUGE crossmember is right in the way, hence why i didn't run it under the headlight (g2s...look).

</TD></TR></TABLE>

yea i was interested in being able to convert mine from a cool-air to a short ram (when it rains). what are you using to make the new box for the filter?

 

i might try the bottom end of a marine battery box (which are plastic) i need to find out what type of materials are heat resitant. I have the template pretty well made, Id like to find some shop of some type to send the dimensions off and maybe have it built witha mirror finish or something, but I doubt ill end up doing that...

I really wanna go to the track and attach the ducting strait to the intake and see how that works...

 

A fine piece of well written work. I loved being the driver to all those special stores to make that project happen!!

 

Thats exactly what I did. Except the blingin' cardboard. Seems to work good and I am not so stressed about water.

 

looks good

try using a baby bathtub (the Endyn way)

 

looks like a ghetto fabulous version of the mugen intake for type R's.... holla!!!

 

Great write up, but where did you get the 'NACA' duct from, I have been looking for one for ages,

Also on the box, how about buying some sheet aluminium from Home Depot, then depending on how well or if you can weld, weld it together, a true DIY mod, plus it would look like something from Top Secret if you had the welds showing.

 

That is not the "correct" use of a NACA duct. (Sorry to nit-pick)
NACA ducts are shaped that way to suck air in when the face of the duct is parallel to the air flow. Like when the duct is on a side window, or flush installed in a hood, or under a vehicle pulling air to cool the differential, etc. They are usually mounted flush.

Not that it hinders your application here, just FYI. I love seeing people "Doing it themselves".
If you are interested, hit up a sign shop for some cheap ABS plastic ($80 per 4'x8' sheet). You can make anything out of this stuff. Make your box, then wrap it in Theremotec heat barrier (Racerpartswholesale.com). That thermotec stuff works VERY well!

 

wow. i would kill myself if i put that on my car LOL..even just as a template... pretty gheto stuff. just curious why you didnt just buy some piping and make your own CAI out of the aluminum tubing that most intakes are made out of rather than that plastic stuff &gt;??

 

You need to use a different type of tubing. The slinky ribbes are going to just disrupt the airflow and kill any type of ram effect you are looking for.

If you really want to do something inovative and functional, look into cowel induction. You already have the first step done, moving the battery.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MrJasey &raquo;</TD></TR><TR><TD CLASS="quote">wow. i would kill myself if i put that on my car LOL..even just as a template... pretty gheto stuff. just curious why you didnt just buy some piping and make your own CAI out of the aluminum tubing that most intakes are made out of rather than that plastic stuff &gt;??</TD></TR></TABLE>

he did, you would know that if you read his ENTIRE post. Nice write up, that will probably keep a few people busy this weekend.

 

hamb18c1: i would love to see how your box came out... the cardboard is just a template, its not in the car, that is just how it will fit, and i know exactly the dimensions for the box when i make it.

ian: any pics of the mugen intake for the R? always looking for improvement.

WOTTEG: yes, i realized this is not the intended purpose of the naca duct, and i even thought about the cut hood but then i have to worry about water. Thought about cutting the fender and trying to mold it in, but if it came out like **** id have to buy another fender...would also have to worry about water. Do you think it would be of better usage (pull more air) if i had the naca duct flat where the resonator was, so that when air went under the bumper right before it hits the tire it would be picked up by the naca duct? then the ducting would only be 2-3 feet long and a strait shot... like in this picture here.


StyleTeg: yes, the only concern of that piping is that there are too many ribs. everything else about it was perfect for the project: black, sturdy, flexible, 3", and cheap. my brother had a cowl hood on his b20/b16 crx and when he put his cf hood on he noticed no difference...I should've labeled this post a source of cold air instead of ram air, because in all actuality i just want the cold air a CAI offers, but the high end power of a SRI, though I am ALWAYS looking for ways of improving this.

for those of you that want to order the duct, i believe i got mine discoverparts.com and it came out to be $20 or so shipped. I think they are located in alabama or something, and i got it in two days.

for the re-version number two. I think I could do a little more..ahem..'body work' by removing some of that 28 pound crossmember, to accomodate two funnels. one would be the location it is now, just run up under the headlight, (i dont know if you guys have space there, but in my g2 where have some room. It would come up right behind the front bumper lense and under the headlight...i will try and get a picture. the second would come up through the resonator hole and would be mounted flush with the bottom of the bumper (so you wouldn't see it unless you were under the car). I don't worry about picking up water because its not a vaccuum, just a source of air. I just dont know if both pipes would fit through that little hole...maybe more cutting will have to be done... on a 10 year old car you get luxuries like being able to cut that **** up...because its already broken and no ones buying it! hahaha.

thanks for the replies, and if you think of anything else, PLEASE let me know how to perfect this project.


I FORGOT....im contemplating this. If i use a 'generic' intake (ill get to that later...) then I could quite possibly run the two ducts a little more efficient. Instead of coming out and trying to bend into the box, I could make the box go over the filter and both of the ducts would just kinda peak in a little bit. maybe something like this

ignore oldness...


now...one duct coming up from the resonator area(from below), and one comnig up from under the headlight (head on) just both have an inch or so of ducting in the box would definately pull a source of cold air.

NOW THE INTAKE...although a nice fit and nice looking, the 3 bended 3" intake may be a little less than what I am going for...the 1 slight bend in my 3" pipe has drawn the most power so far, but I am not sure what I want to do so far...

i do not know everything, i am merely a kid with a lot of stupid ideas and likes to build stupid crap, i would appreciate if one of the racing / physics gurus would pop their head in and tell me how the 3 bends would re-act to the 1 slight bend. obviously i could probobly get more air in, but it is a longer intake which would slow velocity down in my mind...ahhhh too many ideas, not enough answers.


Modified by RedStarGsr at 5:37 PM 8/23/2003

 

Fiberglass for the box??? Not sure if it will be that heat resistant but that may work out well. Just a suggestion

 

any ideas where to get it?

so far i have:

-aluminum and weld a box (have access to a welder)
-ABS plastic
-Fiberglass

what are the ups and downs of each of these? i might have to make a bracket on the bottom so it doesn't resonate and vibrate to pieces...

 

ghetto fresh

let us know how it works out

 

Why dont you get that headlight scoop. It replaces the whole headlight. But yes..its only good for a race day..not daily driving.

 

even if they did make one for my car (which they dont) you are right, not good for daily driver...

and im interested in your a/f guage...

yet some more pictures to get a better view...




you can see how its taped to the funnel, the wrapped around the bumper and up through the airbox hole. you can also see the little piece i cut out for a smoother bend.

if you can imagine a small hole underneath the headlight (as shown) that is where i could run one of the lines (from the front funnel). problem is the crossmember is a beast around that bumper lense.




Modified by RedStarGsr at 9:51 PM 8/23/2003

 

dan,

project looks good, if you are willing to spend the time and effort for what might end up being questionable gains. But, if you like to tinker, this seems like a project worth exploring as I've researched what's available for DAs and there doesn't seem like there's much in terms of intakes from name companies.

as for ducts, more can be found here-
http://racerpartswholesale.com/naca.htm

I've owned stock, aem, comptech icebox and now mugen. of them all, the mugen has the best throttle response while keeping the top end scream.
you're idea of trying to copy the design has merit.

the aem(filter on a stick) had the least low end, massive vtec hit, loudest x-over and decent top end rush. I think it's more the lack of bottom end that makes the top seem like it's more than it is.

the icebox was smoother than the aem at xover, not as loud, but still had a decent top end. didn't feel as much as the aem, but the gains made in midrange up through redline was more to make up for the slight perceptive decline in top end compared to the aem.

the mugen has more mid range than the icebox and once you hit vtec, the motor screams to redline. as much or even more than the aem on top. seems like mugen was able to get the best of both worlds with their design.

speaking of which, the icebox and mugen have very similar designs, but the mugen works a lot better. what could account for the difference in power other than the mugen name?

take a look at the two side by side...






notice on the mugen how much larger the snorkle under the filter is compared to the icebox. I believe the added cubic air space provided by the larger snorkle is key to the different power characteristics of the two intakes. I know the cubic inch displacement of the intakes are different because with the icebox there used to be a resonant frequency "boom" at about 4500rpm. With the mugen, there is a boom at 3000rpm. in comparison, the aem boom was at vtec x-over which is why I think the aem makes so much noise at vtec... x-over+resonant freq=

When I used to ride dirt bikes(enduros) a K&N filter with a larger box around the filter gave you better throttle response. I think that theory applies here, too. You want to increase the dead air space around the filter so that when you open the throttle, it has air to suck in immediately instead of having to suck it in through a long thin straw.

Notice the mugen's taper in the snorkle design. as it moves closer to the filter, it opens up providing that dead air space. You have already found the short ram makes good power which is sort of like have the entire engine bay as your "airbox". problem is the hot air it's sucking in once the engine bay heats up.

my advice to you would be to try and incorporate the stock airbox over the short ram filter and work on a snorkle design connecting the bottom of your stock airbox leading down to the inlet opening. Fiberglass would be my material of choice as you would need to try and maximize the volume of the snorkle with whatever room you have under the stock box and lead that to an open area where you can suck up nice clean, cool air. Your moving the battery out of the way should give you tons of room to do this. You used the front grill area for pickup... have you considered the right front fender area or don't DAs have a hole that leads there? isn't that where the stock resonator sits? I have some reservations on ram air on a street car, but that's my opinion.

BTW, mugen uses fiberglass for the intake. it's light and relatively strong.

good luck with the project. if you need more info I'll be happy to help as I have 2 kids who just bought DAs as their first cars.

thanks,
kelly

 

wow. simply wow. i am glad you enjoy the ethics of a diy project but still are more than willing to help out. Thank you so much for your input.

are you saying that you think the mugen has better throttle response because there is a huge area of air, and since its channeled from the bottom it is all cold?

the das have a hole there where the resonator was...and I can definately use that area for a pickup. should i mount the naca duct flat or try to find something else like a circular pickup (like the mugen).

what do you think about the two ducts coming up? one from the right front fender area and one from the front bumper to under the headlight. if you go outside and look at one of the das (wise choice) you will see a hole roughly 3" wide/tall to squeeze a duct through... if you take the bumper off you can see how i'd have to modify the bumper support (not a problem) but two ducts or two snorkles into the box?

also why do you not like 'ram air' on street cars? and when you said incorporate the stock airbox over the filter do you just mean where the oem filter would be, just use the top half of the airbox over my cone filter, and then start building the large 'snorkle' under that?

 

At this time I do not have a box to cover the actual filter. I am probably going to end up putting the stock box back in. I guess kinda like the type-r ones. Let me know how yours comes out.