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I'm thinking of doing the 90 degree intake that sits behind the passenger headlight. Searched this forum and saw a member had it. It's cheap, beats getting air from the hot side, and I can remove the airbox + everything else for weight savings.
A few questions...
1) What do I do with the MAF sensor and wiring? I guess extend it, but I can't seem to find anything to extend it with.
2) Is there anything else that I need besides the hose, 2 clamps, and filter?
From what I've heard, it's not worth the trouble of extending the MAF wiring.
So then that intake setup is not worth it at all? Is there another way of doing it without extending the wiring?Quote:
Originally Posted by Matt V
What about a DIY cowl intake with a JR airbox filter?
Sorry for all the questions.
The best intake mod I've seen is the Randall cowl intake duct.
http://www.flyinmiata.com/index.php?...umber=05-27000
This is actually proven to give you 5 hp.
i tried the randall style mod and it was no better than the zip tied air filter to the airbox top I had in before...
I'd copy a simple spec miata type intake...cone filter up by the clutch reservoir and a straight tube going from the MAF to said filter. It works.
I know the Spec Miata guys like this as it keeps the A/F balanced.
http://5xracing.com/i-789646-sp-indu...n-bracket.html
That's for the 1.6L, I have the 1.8L. So I don't know if that would work.Quote:
Originally Posted by ken o
I'll probably just leave the intake alone for now. :( I don't want to spend more than $50-60 on the modification, so I don't want to buy pre-fabbed kits.
I've thought about doing an intake on my car for years, just never got around to it.
Primary reasons for me is, throttle response and sound, mainly. The intake I put in the Civic I know didn't make too much of a difference powerwise, but somehow made the car feel lighter and more lively. I loved it, even if it was mostly psycological.
My problem in the summer is engine pinging due to high underhood temps. Which is a a big negative for an aftermarket intake that puts it right by the header causing lots of heat soak. From what I've read putting it on the coldside on an N/A engine takes away low end torque, which i'm not a fan of. I planned to simply install a cone filter on the hot side, leave the intake tube,(i've read it's very well engineered and not a power bottleneck), and take care of my pinging problem at the same time by some clever planning and installing an aluminum heat shield. Done right i've seen people on Miata.net prove temperature benefits over stock this way. I would also plan ahead since I eventually want an aftermarket header.
I wouldn't give up on your project yet. Most of the hot side heat shield setups I've seen cost less than $50. (~$30 cone filter + bunch of random brackets and almuminum sheeting from Home Depot)
When I finally get around to this project, I plan to get a ratty headlight cover and make a DIY NACA air duct to feed the cold box.
Sound, response, temperature control, that's it. Probably not much power, but it seems like an easy project.
Edit: I couldn't find the guy's setup that I was going to rip off :), but if you search Miata.net for something like DIY intake heatshield, or coldbox intake, you'll get lots of different ideas for this seemingly easy mod.
I was thinking about doing the Racing Beat style intake, with the turn signal intakes and/or NACA duct.Quote:
Originally Posted by Jiggerachi
The only problem is that I have a hard time getting the bolts connecting the intake to the airbox off...
http://www.dfwmiata.com/showthread.p...se.&highlight=
Hmmm...I don't seem to have had a problem with mine (if htat's what i'm thinking of). When I get home, if I remember i'll take a look at my airbox to see what's up.
Found a nice website.
http://www.siliconeintakes.com/
Any NB owners with custom intakes that would like to share their work? I've toyed with an intake for my '99, but I'm convinced that I'd just be sucking in hot air from near the header. The cowl intake seems to be the way to go... Like Jiggerachi, I just want the noise factor and any increase in throttle response is a bonus. I don't care if I add power...
Here is my 1.6 intake.
http://www.dfwmiata.com/attachment.p...9&d=1297436672
You could take off the airbox, connect the MAF to a 180 degree silicon hose, then put a K&N style filter on the end of that. It will take air directly behind the driver side headlight. You could also do the NACA and turn signal intakes to increase cooler ambient air.Quote:
Originally Posted by MoonieGT
This is what I'm doing with my NA. I just need to make a decent bracket to hold it all up.
I would think that this, and the cowl style intakes, are the only real beneficial types.
I think the problem is the fact that without isolating the intake you'll be sucking in hot air. Your idea is good, but you still probably need some sort of isolating box for any increased benefit other than sound. The stock airbox is good at insulating heat soak. Remove that and you get direct hot air. If you're running an aftermarket header, they apparently generate lots more heat.
Aiming it behind the headlight might be better, but yy black car, even wth stock header/exhaust heat shield, gets HOT under the hood in teh summer, the entire area, even behind the headlight.
There used to be a knock off RB style aluminum 180 bend pipe with filter on ebay for $30 or so. I never picked it up, but cant seem to find it now.
Oh BTW, he's got an NB, they might be a little harder to fit a NACA duct or even TSIs (???) with the fixed headlights and different front end.
Edit: That intake that JRJ posted with the long arm towards the back, might be a colder area or something, i'm not sure, if that's what the spec guys run, it's gotta be a good solution, but they don't have to worry about stoplights like us street cars.
http://img.photobucket.com/albums/v1...n/IMAG0317.jpg
very cheap version, spend the $40 for a silicone 90*, i did that for my track car before i went boosted
Forgot about that.Quote:
Originally Posted by Jiggerachi
How did you extend the MAF wiring?Quote:
Originally Posted by jeff_man
didn't, the wires are taped in a group, cut it open then retape after removing the wires. also remove the intake air temp wires with you. you are turning one taped up group of wires and making 2, very simple. the wires are coming from under the intake manifold.Quote:
Originally Posted by BFPW
http://www.racingbeat.com/mazda/perf...-shootout.html
Related article from SPC.
So the car comes from the factory with enough wiring? That's news to me, thanks! How well did your intake setup work over stock?Quote:
Originally Posted by jeff_man
less heat from header, car bogs at a stop as there is less air in the intake to suck up but after moving when you stomp on it the throttle response is a lot betterQuote:
Originally Posted by BFPW
This is for NB1. I have the MonsterFlow cross tube/filter/air box. Using the OBDII, even in cool 70 degree overcast days with car crusing at 60MPH, the intake sensor temp reads at least 10 degree higher than the ambient temp! Stopping at the light for more than a couple of minutes, it easily go up more than 20 degree more than the ambient temp. I takes more than a few miles of driving at 30 to 40 mph before the intake temp starts to drop. In the stop and go city traffic that means that the in take temp always run more than 20 degree above the ambient temp with my setup even in a very mild day. Roughly, I am losing about 3% of my hp due to the under hoop temp. In the dog days of summer with a/c at full blast, who knows how much power is lost to the under the hoop heat!!
I than start to experiment with insulating the cross tube with some Thermo King insulating foam with foil backing. I wrap everything double layers. This foam has a R value of 3. I should get a theoretical R value of 6 by double layered. I than ran the same 'unscientific test', The result was pretty much the same! The only difference is that it take longer for the temp to rise while sitting idle. Once everything is heat soaked, it just take as long to get them cool again.
I than read a lot of the posts on the pointy board and talk to several people on this board. I was almost ready to gut everything I have and do the mod Jeff-man had. I than came across a thread about the MonsterFlow cold box is actually NOT air tight and let in a lot of hot air from under the hood. I than use some foam to seal off all the 'holes' and only allow the air to come in from behind the headlight and the gap between the headlight and the radiator. I also put a strip of foam to seal off the space between the hoop and L fender. To isolate the heat from the black color hood, I put another thin layer of foam between the top of the cool box and the underside of the hood. Now the air box is air tight except drawing air from the front. Wow, what a different. The throttle response gets much sharper. More important is that I lose the stumble and sudden surge of power from a standing start. I don't think I get more hp or torque. I think they are just more linear and comes on at lower rpm. I can now accelerate with authority even on my top (5th) gear! The only down side is that the car is louder.
I will do more testing and get more data when the outside temp is higher. Right now the setup is very ghetto looking. I will take some pics once I get it to look better.
Thanks Jeffman. I thought there was an easy NB setup. My issue will be whether or not I can fit a filter in that location... I have the oil filter relocated to that general area...
get a 90* silicon tub and the smallest k&n cone air that will fit over the end of your maf. less then $100 and that is still cheaper then any kit.
Do you have tO get one of those breather filters to replace the hose that goes frome the valve cover to intake tube?
$5 at o'reilly, and good for 1/4hpQuote:
Originally Posted by MoonieGT
I would consider this intake. It's very decently priced and it has an actual heat shield.
http://www.rspeed.net/product_p/na20211060.htm