MAF Sensor? and building your own Cone intake

[abechen]

Do we have the same MAF Sensor as the Matrix XRS?

If so, we may be able to take the K&N kit for the Matrix, cut the pipe, add beading to the cut edge and attach it to the intake. If the length or angle is not right then add a longer/angled samco/silicon hose. If you want to isolate the filter away from the engine, get a sheet of thin alum or a piece of plastic and cut it to size.
Next fabricate another thin piece of metal maybe from the scraps that you cut from the alum into a stablizer bar for mounting.

Filter kit: $180
Sheet Metal: $5
Bead and Cut: $5
Silicon Hose: $20

$210

[Hollywood]

Originally Posted by abechen

Do we have the same MAF Sensor as the Matrix XRS?

If so, we may be able to take the K&N kit for the Matrix, cut the pipe, add beading to the cut edge and attach it to the intake. If the length or angle is not right then add a samco hose. If you want to isolate the filter away from the engine, get a sheet of thin alum or a piece of plastic and cut it to size.

Filter kit: $180
Sheet Metal: $5
Bead and Cut: $5
Silicon Hose: $20

$210

you could always get a used one off of ebay and cut it up. that way if you mess up it you wont be out to much maybe 50 at the most.

i plan on doing one in the next couple of weeks or so

[Stan]

You can get ebay intakes for the various 2zzge cars for under 30 dollars...like 22 IIRC. Once you have the tube with the MAF provision, the rest is not hard as far as getting something to function. Some tuning via swapping stuff around may be needed. You can run just about any brand of cone filter you'd like.

[ChrisH]

Originally Posted by Stan

You can get ebay intakes for the various 2zzge cars for under 30 dollars...like 22 IIRC. Once you have the tube with the MAF provision, the rest is not hard as far as getting something to function. Some tuning via swapping stuff around may be needed. You can run just about any brand of cone filter you'd like.

I am not sure how I would pick what would really work from ebay, versus what is just junk or stupid. Could you maybe give a link with an example or two that you think would work? (Obviously, no guarantee.)

[SweetDaddyD]

I'd be willing to bet that if you just hack together an intake to fit in there you may improve the volume of air with a different filter but more than likely you will still hinder performance by F-ing up the Airflow. I would be willing to bet this because I used to work in an airflow room in my previous job and you wouldn't believe the money the OEM manufactures paid us to test and develop properly engineered airflow systems. One of the biggest concerns was always eliminating "noise" over the hotwire of a MAF sensor. A lot of money goes into figuring out the velocity, resonance, etc. You know that piece of "honeycell" that often resides in part of an intake tract? The one that every boy racer or "tuner" pulls out because he read on the internet that it was a restriction and he'd get at least 5 HP by yanking it? Well guess what, it's in there to do something, believe me, the manufacturer wouldn't spend the extra $1 to put it in if it wasn't doing anything (it straightens out the airflow to reduce turbulance over the hotwire). I know the generic style tube intake and k&n cone filter I purchased from E-bay actually hindered my BMW's performance and a lot of times a sudded WOT induces a nice bog now. It does make a much cooler sound though. haha. Not to mention that excess oil in the airstream often reeks havoc on sensors. There is a little saying that holds true it seems like too often- "You get what you pay for" If you get a sysem engineered under a 16 year old hacksaw in his basement with the cheapest cone filter sourced out of China, don't be suprised it you hinder performance more than helping it.

[Stan]

>>>I am not sure how I would pick what would really work from ebay, versus what is just junk or stupid. Could you maybe give a link with an example or two that you think would work? (Obviously, no guarantee.)<<<

Well if you are a detail oriented sort, willing to try stuff out and go through a few changes with no guarantee of instant success....the main thing you need is the MAF holder tubing. You can get this from a junk yard air filter box for a 2ZZ car for example. You can put a reputable air filter on your intake.

Here's are some example "ebay intakes". They appear to be made to sell on Ebay. The main component you'd need to scavenge is piping with the MAF flange on it. You can cut away any excess pipe. Ideally you'd want to measure and examine know good systems and make a few iterations and measure the results (AFR, Acceleration via a logger or on a dyno...)

http://cgi.ebay.com/ebaymotors/ws/eB...category=38634

http://cgi.ebay.com/ebaymotors/ws/eB...category=38634

http://cgi.ebay.com/ebaymotors/ws/eB...category=38634

http://cgi.ebay.com/ebaymotors/ws/eB...category=38634

[Bill B]

I've started to fab one for my car. I'll keep you posted.

[Beanie]

Here's what I'm using for a filter with a heat shield. It's called a Green Twister and is from ESAD, a German company. $178 shipped. The heat shield is stainless, I think. It's a nice piece of work.

(pics removed... see link in a post further down)

It's the green one. I've tried the others... this is better. The reddish one works well, but isn't shielded. As long as you have adequate airflow through the engine bay (at least where the filter is), it might actually be better than the Twister. The Twister could be larger (have more surface area), but it's pretty close to what would be perfect, IMO.

You can use a cheapie eBay intake for the MAF mount and 2.5" O.D. tubing. Get some silicone couplers with 45 degree bends and some thin rubber hose that's 2.5" O.D. to adapt the 2.5" O.D. intake to the 2.75 (70mm) I.D. Green Twister. Connect a 3.0" I.D. flexible hose from McMasters Carr to inlet of Green Twister and run the other end to the side vent.

(pics removed... see link in a post further down)

These two engines (1ZZ and 2ZZ) are not all that different until lift kicks in. For my 2ZZ I'm going to replace just the short (6" long) MAF mount tube with a 2.75 O.D. part (probably cut out of an eBay intake for something or other), since I'll have a Power FC with that.

Hope you guys don't mind me sharing my information with you, even though my car is different.

By the way, SweetDaddyD make a good point. That's why my custom-made MAF mount pipe has the exact same structure inside the tube, 1" before the MAF. Idle stinks without it. HOWEVER, if the tube is smaller than stock, as these things tend to be, velocity is increased and you may not have much turbulence. That structure in there (I call it a U gate or vanes) is somewhat restrictive. It doesn't bother a 1ZZ, but a 2ZZ may need the extra airflow at higher RPMs. I'm undecided on whether to have another custom one fabbed with that structure (scaled up) when I get the 2ZZ conversion done.

[ChrisH]

Is the Elise's standard MAF sensor a good one, or are there better ones available, and would that make a difference? Would upgrading the MAF mess up the ECU and/or cause the check engine light to be on?

How does one tune the diameter of the intake to the length, airflow and sound desired?

[Greg]

Isn't it pretty well understood that the K&N filters suck? Apparently they have some oil coating or something that destroys MAF sensors. Is the Totyota MAF sensor more resilient to this than others?

Disconnecting the MAF should definitely throw a DTC, but presumably you already knew that and have the tools to read the codes, and reset.

'Greg

[ChrisH]

A lot of performance filters have an oil coating, such as ITG's. I am also curious if there are any problems with using an oil coating. A dry filter (like paper) seems pretty safe from the point of view if not introducting oil or other coatings into the air flow.

[Stan]

I've been using a K&N panel filter on my car for some time...no issues at all. Many folks overoil K&Ns after they clean them.

[Tigris]

screwing with the maf tube by using a ebay tube is a bad idea. The tube needs to be the same shape/diamter(unless you get tuned with it) The wrx guys all ran injens for awhile, but went back to stock after people started popping motors due to the intakes fooling the ecu into running lean. Next generation intakes were machined to match the stock maf. One cheap way to get around this is to maybe hack a stock airbox and throw a universal k+n on there?

[Stan]

>>>screwing with the maf tube by using a ebay tube is a bad idea. The tube needs to be the same shape/diamter(unless you get tuned with it) The wrx guys all ran injens for awhile, but went back to stock after people started popping motors due to the intakes fooling the ecu into running lean. Next generation intakes were machined to match the stock maf. One cheap way to get around this is to maybe hack a stock airbox and throw a universal k+n on there?<<<

You have to be willing / able to fiddle around with this stuff. I've designed / built / tested a number of intakes for BMWs. Generally speaking you need to go through a few iterations and plan on measuring things to get the best out of a setup.

[SweetDaddyD]

There's no problem with using a oiled filter, as long as none of that oil gets on the MAF sensor (sarcasm) With all that air going through the filter, it's easy for a little oil vapor to get in the airstream and coat your sensor, rendering it useless. Sometimes you can clean it with injector cleaner, sometimes your screwed. Usually happens when the oil is fresh. A little bit of excess and by by sensor.

[Beanie]

Fooling the ECU, making the engine run a tad leaner for more power, seems to rather consistently give a noticeable increase of about 5-6HP on an engine this size. I had an AEM on my car for a long time, but also had a Power FC that made it run richer at higher RPMS and loads, so it was fine. Whether it is dangerous or not depends on what the AFR is and I have no idea how Lotus tuned this ECU, except that it is probably quite similar to the Celica GT-S. I would think that whatever is recommended by the truly knowlegeable GT-S guys would be good.

The oil buildup isn't bad as long as you clean the MAF about as often as you change your oil. Most people use carb cleaner and I don't see how that would do any harm. Squirt a lot of carb cleaner up inside where the two wires are and let it sit for bit, then dump it out and let it dry throroughly. There's also the clear plastic "bulb" that tends to get brownish. It is harder to clean. I have had the same MAF for 40K miles and worst case, I'd have to replace it.

There are better MAF sensors... less restrictive. I remember seeing one that curved back into the airflow. It appeared to be a simple curved tube that protruded.

Paper filters aren't the best in terms of filtration, but the ones I've used do a good enough job, I think. The ones you can buy at Pep Boys with the inverted cone at end (like the red one in my pic) are so cheap (about $25) that you can just replace them every 3000 miles. They are not very restrictive at all.

---

Edit: This came up on Spyderchat. Someone who's opinion I trust recommended the Pro-M MAF and I just found this info: http://www.mustangworks.com/articles...tionBlues.html

You really have to know what your AFR is when changing these things.

This looks interesting: http://www.mustang50magazine.com/how...af/index1.html

[Beanie]

EDIT: I've updated this intake and there's no point in duplicating all that here, so here's a link to the topic on Spyderchat. This may be the last intake I ever make, although I do plan to modify or swap out the MAF mount tube when the 2ZZ goes in. There might be some other way to improve upon it beyond that, but I really don't think so at this point in time. http://www.spyderchat.com/phpBB/viewtopic.php?t=22497

[ChrisH]

Pictures and instructions, please.

Audio recording, please.

Also, link to GTS eBay special.

Enquiring minds want to know.

[Stan]

Sample ebay special URLs further up in the thread.

[Beanie]

Originally Posted by MyElise

No vanes in the Elise tube.

I asked this question ages ago and was told that it has them. If they are there, they would be about 1" before the center of the MAF hole.