Gene's DIY CAI thread

[Bonestock]

Hey guys, while Gene aka 92 SVX was over working on his interior wrap project I spotted a very nice and cost effective mod he had made to his car. A low cost cold air intake (CAI) made from off the shelf parts found at your local parts store. I believe the total cost is around $75??

I have now dubbed his intake the "GDIY" (pronounced Gee-dee) mod I am hoping I can encourage him to do up a "how too" with at least the part numbers needed to copy his work.... :cool:

Here ya go Gene.. your very own mod. You deserve it because its simple, cost effective and a classic case of hot rodder ingenuity.

C'mon Gene!

[92 SVX]

Hey guys, while Gene aka 92 SVX was over working on his interior wrap project I spotted a very nice and cost effective mod he had made to his car. A low cost cold air intake (CAI) made from off the shelf parts found at your local parts store. I believe the total cost is around $75??

I have now dubbed his intake the "GDIYCAI" (pronounced gid-dy cah-eye) I am hoping I can encourage him to do up a "how too" with at least the part numbers needed to copy his work. OK, the name might need some work... :cool:

Here ya go Gene.. your very own mod. You deserve it because its simple, cost effective and a classic case of hot rodder ingenuity.

C'mon Gene!

Thank you, ok I will attempt to explain it though Im better at doing then explaining.

[92 SVX]

Ok Here it goes.

First I started by cutting out the Accordion section of the stock tube, for 2 reasons first it allows lots of movement, and second using smooth walled tubing should help air flow.

I cut it as close to the idle control nipple as I could and still put a silicon coupler on you can cut it with a hacksaw. I think I used tin snips. I used a 3" silicon coupler from oreilly's. Part # 8771
http://images.oreillyauto.com/parts/img/sct/8771.jpg $7.99 needs 3 for my setup. I also needed to heat it up just a little to open enough to go on.
Then into that goes a 22 degree bend part #8728
http://images.oreillyauto.com/parts/img/sct/8728.jpg
at $11.99. This will connect to a 4" straight piece part #8708 using the clamps that come with all these pieces $8.99
http://images.oreillyauto.com/parts/img/sct/8708.jpg
Which then connects to a 45 degree bend
http://images.oreillyauto.com/parts/img/sct/8738.jpg

Part #8738 $11.99. Using the second of the silicon couplers this attaches to the stock MAF again needing some heat to fit. Then maf adapter part number #81413 $13.99
http://images.oreillyauto.com/parts/img/sct/81413.jpg
Discarding the plastic piece as it is for a smaller diameter piping. You will need to line up the inside and drill new holes to fit your maf.
Then the maf adapter couples to the 90 degree bend part #8698 $10.99
http://images.oreillyauto.com/parts/img/sct/8698.jpg
Then that attaches to a 6" straight part #8718 $9.99
http://images.oreillyauto.com/parts/img/sct/8718.jpg
Then put your filter on the end. I had a filter so that was not included in the price but if you need one part #8136
http://images.oreillyauto.com/parts/img/sct/8136.jpg
cost $24.99
With out the filter it was $91.99 A little higher then my initial estimate.
That is what I did as I pieced them one at a time if you want you can get the short ram part # 8208 for $39.99
http://images.oreillyauto.com/parts/img/sct/8208.jpg
comes with one coupler and 2 4" and the 45 bend which means you would only need the 22 bend the 90 and 2 couplers. You do need a straight piece inside the fender but the 4" may be enough I had the 6" so that is what I used.
Using the Short Ram without filter its $78.95
http://localserver.no-ip.biz/Public/SVX%20CAI%20entire.jpg

[92 SVX]

I also went and did the crank case breather mod.

http://localserver.no-ip.biz/Public/SVX%20crankcase%20breather.jpg

[Bonestock]

Nice, great write up Gene!

[Bonestock]

I wonder if this is a direct fit to our stock MAF?

http://i17.photobucket.com/albums/b86/BVM03/maf.png

[Bonestock]

I have been looking on ebay for any CAi's that look as though they have a similar layout to the SVX.

Back in my Fiero days, it was discovered that a CRX CAI was a direct fit on a Fiero V6.

[dennyo]

Looks good gene. What's the purpose of the tube on either side of the maf? just a bypass?

[92 SVX]

Looks good gene. What's the purpose of the tube on either side of the maf? just a bypass?

Yes a bypass, I read on here a member did that because the stock maf is the limiter this will allow some unmetered air at wot supposed to give a small boost in power. I thought it isnt hurting why not.

[Lookin4SVX]

I used a 94-97 Honda Accord Cold Air Intake off ebay (http://cgi.ebay.com/ebaymotors/Honda-92-96-Prelude-94-97-95-Accord-Air-Intake-Filter_W0QQcmdZViewItemQQcategoryZ38634QQitemZ3704 73212339) on my 2001 impreza RS.

http://images.channeladvisor.com/Sell/SSProfiles/60000086/Images/6/55-0131PR.jpg

I just sawed off that last bend on the end that I didn't need.

http://i923.photobucket.com/albums/ad73/Lookin4SVX/hondastyle.jpg


http://i923.photobucket.com/albums/ad73/Lookin4SVX/gonzflowstyle01.jpg


Holding this pipe in my hand has me thinking...
If I was to take it and flip it over.. would it .. maybe?
http://i923.photobucket.com/albums/ad73/Lookin4SVX/photochopintakeinsvx.jpg

hmmmm.. photochop says maybe... if my svx wasnt parked under a snowbank...

[svxfiles]

Yes a bypass, I read on here a member did that because the stock maf is the limiter this will allow some unmetered air at wot supposed to give a small boost in power. I thought it isnt hurting why not.

Are you running a higher pressure fuel pressure regulator?
Without it you will be running way lean, at the lower RPMs.:eek:

[Bonestock]

I used a 94-97 Honda Accord Cold Air Intake off ebay (http://cgi.ebay.com/ebaymotors/Honda-92-96-Prelude-94-97-95-Accord-Air-Intake-Filter_W0QQcmdZViewItemQQcategoryZ38634QQitemZ3704 73212339) on my 2001 impreza RS.



I just sawed off that last bend on the end that I didn't need.




Holding this pipe in my hand has me thinking...
If I was to take it and flip it over.. would it .. maybe?

hmmmm.. photochop says maybe... if my svx wasnt parked under a snowbank...

Funny you mention the Accord. I was looking at the 90-93 Accord CAI on ebay. For $40 it may be worth a try!

[92 SVX]

Are you running a higher pressure fuel pressure regulator?
Without it you will be running way lean, at the lower RPMs.:eek:

Will running lean cause higher fuel consumption? It seems no matter what I do I can not get this thing to get better then 22-24 highway mileage.
The bypass has only been on 5-6 days I can just plug the holes. I am not running any higher pressure fuel at the moment. A mod I have been thinking about but not ready to get into.

[svxfiles]

Will running lean cause higher fuel consumption? It seems no matter what I do I can not get this thing to get better then 22-24 highway mileage.
The bypass has only been on 5-6 days I can just plug the holes. I am not running any higher pressure fuel at the moment. A mod I have been thinking about but not ready to get into.

About 100 years ago (around 2001) Mychailo did some testing with an actual WIDEBAND! And found out that the A/F ratios were very lean at idle and very rich at high RPM.
I was already running a higher pressure fuel pressure ratio regulator from an 2000 Legacy, (43.5 as I remember, compared to our stock 36.3 psi) and I "felt/tested" some improvement in accelleration!:D
He, Mychailo came up with the bypass mod which worked in conjunction with the higher PSI FPR to make a flatter, better A/F ratio for more better power.:)
This mod is probably better for the SVX people who cannot just buy a chip that adjusts the timing for evan better results!

[92 SVX]

About 100 years ago (around 2001) Mychailo did some testing with an actual WIDEBAND! And found out that the A/F ratios were very lean at idle and very rich at high RPM.
I was already running a higher pressure fuel pressure ratio regulator from an 2000 Legacy, (43.5 as I remember, compared to our stock 36.3 psi) and I "felt/tested" some improvement in accelleration!:D
He, Mychailo came up with the bypass mod which worked in conjunction with the higher PSI FPR to make a flatter, better A/F ratio for more better power.:)
This mod is probably better for the SVX people who cannot just buy a chip that adjusts the timing for evan better results!

I plugged them I am getting the ecutune stage 1 so it would appear I would not need the bypass presently.

[svxfiles]

I plugged them I am getting the ecutune stage 1 so it would appear I would not need the bypass presently.

It is still a clever way around the 250 hp threshold.;)

[Bonestock]

Quick pic with my cell phone. Thanks to Gene for an awesome and cost effective mod! Thanks mate!!!! :D

http://i17.photobucket.com/albums/b86/BVM03/0211011723.jpg

I used the small grey 3" MAF adapter from auto zone and redrilled the bolt pattern to fit the stock MAF and trimmed off the corners.

I also used a K&N E-0773 filter.

On Gene's parts pic I used the small L shaped bracket and re-drilled the hole about 3/4 closer to the bend. Stuck the small end under the hose clamp closest to the inner fender and bolted it to the rubber mount where the air inlet tube used to bolt on.

[Lookin4SVX]

So you have a cone filter is inside the passenger fender?
How do you clean it/install it?
Do you have to remove the fender or does the filter fit through the hole in the fender from under the hood?

Doesn't the stock air box take in air from the same hole your using to stick the cone filter through?
So why not just leave the stock box there and put in a high flow rectangular filter in it?

Are there any #'s for replacing just the accordion plastic to the MAF compared to a full intake into the fender, on the SVX?

I know on my 2001 Impreza, removing the box and going to a pipe with a cone filter on the end decreased low end torque.
That the air in the box at the ready helped the performance, that is why the "gonzflow" style makes use of the stock box and filter, instead of a pipe and cone on the end.
Then again, the air filter box on my impreza was at the motor, not the fender, and I didn't have this MAF stuff to deal with.

I am just wondering if its worth the trouble switch to a cone in the fender.

[92 SVX]

You need to remove the splash shield in front of the front tire to access the filter, not a big problem. It will all be accessible from under the car not in the engine bay.
The stock box has a resonator in that location inside the fender, that resonator decreases air flow to the stock box. Remove the resonator and keep the stock box is an option but the main benefit of this type of CAI is smooth air flow from the outside to the throttle bodies.

[oab_au]

You need to remove the splash shield in front of the front tire to access the filter, not a big problem. It will all be accessible from under the car not in the engine bay.
The stock box has a resonator in that location inside the fender, that resonator decreases air flow to the stock box. Remove the resonator and keep the stock box is an option but the main benefit of this type of CAI is smooth air flow from the outside to the throttle bodies.

No that is not right.:) The stock air box takes cold air in from under the front, and suppresses the sound. It does not restrict the air flow.
The only advantage of modifying it is to say" look at what I've got." :D

Harvey.

[Bonestock]

No that is not right.:) .
The only advantage of modifying it is to say" look at what I've got." :D

Harvey.

I haven't disagreed with something this much in the history of EVER! But, you have the right to your opinion.

:cool:

[Bonestock]

See bold sections for my response.

So you have a cone filter is inside the passenger fender?
How do you clean it/install it?
Do you have to remove the fender or does the filter fit through the hole in the fender from under the hood?

Easiest way is to clean it when you rotate your tires... you do rotate them every other oil change... yeah? Take two minutes and a 10mm socket and ratchet to access the filter.

Doesn't the stock air box take in air from the same hole your using to stick the cone filter through?
So why not just leave the stock box there and put in a high flow rectangular filter in it?

Yes, but what you don't see is the fresh air inlet makes a U shape inside the inner fender plus the resonator chamber. The inlet sets about even with the back of the headlight.. pretty close to it too.


Are there any #'s for replacing just the accordion plastic to the MAF compared to a full intake into the fender, on the SVX?

The accordion bit is there to give the intake some flex since the engine isn't sold mounted to the chassis. If you just want to replace that bit, I believe SVX Motorsports Warehouse has a pipe.

I know on my 2001 Impreza, removing the box and going to a pipe with a cone filter on the end decreased low end torque.


How do you know that? Did you swap them out on a dyno between runs? I ask because in my entire life I cant say that I have ever seen a car not benefit from a "free flow" or CAI... unless the system was flow limited further down stream. Furthermore I assume you are speaking about "peaks". What about area under the curve? Sometimes you may trade a bit of HP for TQ or vise-versa but typically the gains far exceed the any losses.

That the air in the box at the ready helped the performance, that is why the "gonzflow" style makes use of the stock box and filter, instead of a pipe and cone on the end.
Then again, the air filter box on my impreza was at the motor, not the fender, and I didn't have this MAF stuff to deal with.

I am just wondering if its worth the trouble switch to a cone in the fender.

I think so but YMMV

[Lookin4SVX]

Ok, so to clean the filter you go at it from the wheel well, by removing the wheel and the wheel well liner?
This is a problem for me. The previous owner had the bumper repaired. When they repaired it they did a really half ass job on it. They made some new supports out of metal bits, and then riveted the fender liner to it and to the car. So my passenger wheel liner is no longer removable.

My oil is changed by a shop, and my tires are rotated by the tire place.
I don't even own a jack.

The plastic silencer crap in the fender has already been removed.

Ok, accordion pipe is there so I don't break it with my shot motor mounts.
Yes, I was thinking like that polished B pipe. Guess I will wait till after I get new mounts.

There is many, many, many, a thread on NASIOC about impreza intakes.
It stated over and over again, removing the air box on an impreza, hurts performance.
The Cobb intake, the one that deletes the air box, has a large sweeping curve to keep the low end torque up.

I know very little about my svx, that is why I am asking. I was driving the impreza for 9 years.

[Bonestock]

Ok, so to clean the filter you go at it from the wheel well, by removing the wheel and the wheel well liner?
This is a problem for me. The previous owner had the bumper repaired. When they repaired it they did a really half ass job on it. They made some new supports out of metal bits, and then riveted the fender liner to it and to the car. So my passenger wheel liner is no longer removable.

My oil is changed by a shop, and my tires are rotated by the tire place.
I don't even own a jack.

The plastic silencer crap in the fender has already been removed.

Ok, accordion pipe is there so I don't break it with my shot motor mounts.
Yes, I was thinking like that polished B pipe. Guess I will wait till after I get new mounts.

There is many, many, many, a thread on NASIOC about impreza intakes.
It stated over and over again, removing the air box on an impreza, hurts performance.
The Cobb intake, the one that deletes the air box, has a large sweeping curve to keep the low end torque up.

I know very little about my svx, that is why I am asking. I was driving the impreza for 9 years.


LOL Don't believe everything you read on NASIOC. But typically they are talking about short rams. Those are terrible because they suck up under-hood heat. I have tested this stuff over and over using ECUTEK Delta Dash on my old JDM V8 STi/V7 6MT swapped, 20g WRX. And have more dyno pulls testing various parts back to back than you can imagine.

Now there are a few caveats but I really don't feel like getting into it. Besides until you get your car fixed properly, you can not benefit from this thread.

[oab_au]

I haven't disagreed with something this much in the history of EVER! But, you have the right to your opinion.

:cool:

No not just my opinion.:)Some time ago, a member ran a test of the pressure in the plenum at full throttle and high rpms, with the standard air box and filter. He found that it was virtually atmospheric, no restriction at all.:)

Harvey.

[Jake@FAPFab]

i'd have to say this is the best bang for buck intake. although buying a few mandrels and straight from the columbia river mandrel b-list pipes might be cheaper. but then you'd need to weld

[Bonestock]

No not just my opinion.:)Some time ago, a member ran a test of the pressure in the plenum at full throttle and high rpms, with the standard air box and filter. He found that it was virtually atmospheric, no restriction at all.:)

Harvey.

Get it on a dyno and then we will see. :cool: IF there was no restriction or benefit from cleaning up the air flow to the T/B those split intakes wouldn't of made any additional power.... but they did. Posted on this very forum.

[Jake@FAPFab]

pressure=/=airflow

[svxfiles]

pressure=/=airflow

Jake, are you saying that pressure does not equal airflow?


Just asking about your equation.:o

[SVXRide]

Harvey,

That would be me. Point to note is that I was running a full ram air system from the front bumper to the stock airbox, with a "Green" filter in the airbox when I took the measurements. New "Scorpion" system is replacing the stock TB to stock airbox system as soon as I can get some welding done :rolleyes: (oh, and fingers crossed that the hood still closes without modification ;))

-Bill

Bumper to airbox:
http://www.subaru-svx.net/photos/files/SVXRide/24195.jpg

Scorpion:
http://www.subaru-svx.net/photopost/data/500/medium/Scorpion_II.jpg

[svxfiles]

Harvey,

That would be me. Point to note is that I was running a full ram air system from the front bumper to the stock airbox, with a "Green" filter in the airbox when I took the measurements. New "Scorpion" system is replacing the stock TB to stock airbox system as soon as I can get some welding done :rolleyes: (oh, and fingers crossed that the hood still closes without modification ;))

-Bill

Bumper to airbox:
http://www.subaru-svx.net/photos/files/SVXRide/24195.jpg

Scorpion:
http://www.subaru-svx.net/photopost/data/500/medium/Scorpion_II.jpg

Sure Bill, that hood will close....
If you slam it REAL HARD!!!!!




Oh, and thanks for that return phone call.......:rolleyes:

[Jake@FAPFab]

Jake, are you saying that pressure does not equal airflow?


Just asking about your equation.:o

yes, no JSMath functions on phpbb!

The pressure at the plenum/iris is one thing, but the cfm across the entire system is another.
The stock intake does a poor job FLOWING, but has a relatively low pressure drop across the air filter. I speculate that the "ribs" or stretch section do the most damage.

[sicksubie]

And what hood is this, Bill?

[LetItSnow]

Get it on a dyno and then we will see. :cool: IF there was no restriction or benefit from cleaning up the air flow to the T/B those split intakes wouldn't of made any additional power.... but they did. Posted on this very forum.
Interested... Was there benefit or detriment under 4200RPM? Resonance doesn't discriminate, and MAF technology hasn't changed much. I'd really like to see some dyno action from the other end of the RPM spectrum, which has been proven to suffer from this sort of mod in other applications.

[Bonestock]

I'll post up some dyno results this summer when I head over to MASE Engineering. I have no problem swapping parts on a dyno day! :D

I have to get that 3rd pedal I have been wanting and finally a Hydra ECU before then.

On another note, after my recent mods (see my thread in the general section) and a good dose of seafoam I can finally feel a distinct step in power when I get on it from a standing start.

[oab_au]

Harvey,

That would be me. Point to note is that I was running a full ram air system from the front bumper to the stock airbox, with a "Green" filter in the airbox when I took the measurements. New "Scorpion" system is replacing the stock TB to stock airbox system as soon as I can get some welding done :rolleyes: (oh, and fingers crossed that the hood still closes without modification ;))

-Bill


Nah Bill, you were second on the scene, I was referring to Mychailo's post.:)

http://www.subaru-svx.net/forum/showthread.php?t=26652

Harvey.

[SVXRide]

Nah Bill, you were second on the scene, I was referring to Mychailo's post.:)

http://www.subaru-svx.net/forum/showthread.php?t=26652

Harvey.

Harvey,

You are correct. I actually borrowed Mychailo's instrumentation when I did my instrumented runs.:cool:

-Bill
p.s. the hood is a classic glass fiberglass piece. fingers crossed that I won't have to do any cutting, but I have my doubts;)

[icingdeath88]

Harvey,

You are correct. I actually borrowed Mychailo's instrumentation when I did my instrumented runs.:cool:

-Bill
p.s. the hood is a classic glass fiberglass piece. fingers crossed that I won't have to do any cutting, but I have my doubts;)

So what's the story with the "scorpion" intake? Will it do anything the tomyx style intake wouldn't do? Regardless, that looks really badass dude. I could see something like that pulling air from a filter under a hoodscoop. I wonder what that would do in terms of power.

[svxfiles]

Harvey,

You are correct. I actually borrowed Mychailo's instrumentation when I did my instrumented runs.:cool:

-Bill
p.s. the hood is a Class Glass fiberglass piece. fingers crossed that I won't have to do any cutting, but I have my doubts;)


Bill, with some solid mounts we could drop your engine 2" for a lower center of gravity AND more hood clearance!
Less angle in the driveshaft as well!
BTW, phone broken?
:p

[Myxalplyx]

/subscribe

Nice DIY intake! Love this stuff! As for the other stuff around what will work and what doesn't......Will just keep reading. :p

[Johnybeas]

... and finally a Hydra ECU....

still waiting for a reply to the pm I sent you...

[Bonestock]

still waiting for a reply to the pm I sent you...

And when I am ready, I'll let you know.

[92 SVX]

OK I finally got around to taking a few more pictures of my CAI
This is what it looks like now

http://localserver.no-ip.biz/Public/The%20CAI%20Aug%202011%20%281%29.jpg

http://localserver.no-ip.biz/Public/The%20CAI%20Aug%202011%20%282%29.jpg

http://localserver.no-ip.biz/Public/The%20CAI%20Aug%202011%20%283%29.jpg

The line going to the valve cover is the breather, I removed the pcv system and replaced it with a breather filter and this line was apparently venting to atmosphere. I started getting fumes in the car

[httrdd]

Very nice diy mod! I am going to build this on the LGT! :D

[steveherman]

Ok Here it goes.

First I started by cutting out the Accordion section of the stock tube, for 2 reasons first it allows lots of movement, and second using smooth walled tubing should help air flow.

I cut it as close to the idle control nipple as I could and still put a silicon coupler on you can cut it with a hacksaw. I think I used tin snips. I used a 3" silicon coupler from oreilly's. Part # 8771
http://images.oreillyauto.com/parts/img/sct/8771.jpg $7.99 needs 3 for my setup. I also needed to heat it up just a little to open enough to go on.
Then into that goes a 22 degree bend part #8728
http://images.oreillyauto.com/parts/img/sct/8728.jpg
at $11.99. This will connect to a 4" straight piece part #8708 using the clamps that come with all these pieces $8.99
http://images.oreillyauto.com/parts/img/sct/8708.jpg
Which then connects to a 45 degree bend
http://images.oreillyauto.com/parts/img/sct/8738.jpg

Part #8738 $11.99. Using the second of the silicon couplers this attaches to the stock MAF again needing some heat to fit. Then maf adapter part number #81413 $13.99
http://images.oreillyauto.com/parts/img/sct/81413.jpg
Discarding the plastic piece as it is for a smaller diameter piping. You will need to line up the inside and drill new holes to fit your maf.
Then the maf adapter couples to the 90 degree bend part #8698 $10.99
http://images.oreillyauto.com/parts/img/sct/8698.jpg
Then that attaches to a 6" straight part #8718 $9.99
http://images.oreillyauto.com/parts/img/sct/8718.jpg
Then put your filter on the end. I had a filter so that was not included in the price but if you need one part #8136
http://images.oreillyauto.com/parts/img/sct/8136.jpg
cost $24.99
With out the filter it was $91.99 A little higher then my initial estimate.
That is what I did as I pieced them one at a time if you want you can get the short ram part # 8208 for $39.99
http://images.oreillyauto.com/parts/img/sct/8208.jpg
comes with one coupler and 2 4" and the 45 bend which means you would only need the 22 bend the 90 and 2 couplers. You do need a straight piece inside the fender but the 4" may be enough I had the 6" so that is what I used.
Using the Short Ram without filter its $78.95
http://localserver.no-ip.biz/Public/SVX%20CAI%20entire.jpg

All the pictures are gone.
Kinda makes this thread less helpful.

[NineBreaker]

Bump on these pictures.
I have an understanding. just would like to see what has been done.

[LetItSnow]

Just a little searchy with the part numbers gives these goods:

http://www.summitracing.com/parts/spe-8771
http://www.summitracing.com/parts/spe-8728
http://www.summitracing.com/parts/spe-8738
http://www.summitracing.com/parts/spe-81413
http://www.summitracing.com/parts/spe-8698
http://www.summitracing.com/parts/spe-8718
http://www.summitracing.com/parts/spe-8136
http://www.summitracing.com/parts/spe-8208

Probly looks a good share like this when done:
http://s17.photobucket.com/user/BVM03/media/0211011723.jpg.html

I'll let you do the rest.

[92 SVX]

webserver is down sorry