Homemade CAI for $135.67

[TurboMatt]

Teaser:

http://i201.photobucket.com/albums/aa265/maynardme/CAI/IMG_0175.jpg

I made this CAI for less than $140. Details to follow. :secret:

[TurboMatt]

I'm old.

Okay, I'm not *that* old, but I'm old enough that 300 bones sounds like way too much money for a dang air filter and some tubing. I'm also old enough to remember when hot rodders actually made their own modifications... running dryer duct from underneath the bumper up to your air cleaner housing, cutting out the block-off from your Trans Am's shaker scoop, and making a dual exhaust system from flexible pipe and JC Whitney turbo mufflers. :mullet:

On top of that, I'm a cheapskate.

Anyway, I started with this:

http://i201.photobucket.com/albums/aa265/maynardme/CAI/IMG_0152.jpg

That's a 4-inch OD steel mandrel bend with a 6-inch radius ($43.77), silicone couplers and SS clamps ($62.90), and a 10" Spectre cone filter with a 4" inlet ($29), all sourced off the internets. I already had a brass nipple and some 3/8" hose lying around for the vent hose. I used some leftover cast iron gray paint and clearcoat to paint it.

I cut the bend like this:

http://i201.photobucket.com/albums/aa265/maynardme/CAI/IMG_0174.jpg

The middle cut is at approximately 102 degrees. The lower left cut is right where the bend ends. The lower right cut leaves about 2" of straight pipe below where the bend ends.

Top right segment = throttle body to MAF (orient it so that the 2-inch straight piece is toward the MAF)
Top left segment = MAF to air filter
Discard the remaing pieces.

The silicone couplers are as follows:

Throttle body: 4" straight coupler
MAF outlet: 4" hump hose (allows some engine movement)
MAF inlet: 4.0" to 3.75" reducer

The MAF outlet is actually 3.75", so I used a spacer that came with the Spectre air filter so the 4" hump hose would fit on it. That wasn't my original plan, but it worked out great.

Once everything's mocked up in the engine compartment, mark a hole near the TB for the vent hose nipple. Make sure you drill the hole and fit the nipple before you paint it. I used a 5/16" nipple with 1/4 NPT threads because it's what I had... I had to use a clamp on the 3/8" hose to get it to stay in place.

The air filter will rest against the frame, so for now I have some blue masking tape covering the area to protect the paint. I plan to pick up some wide foam insulation tape from Home Depot to put on there.

Here's another pic of the final result:

http://i201.photobucket.com/albums/aa265/maynardme/CAI/IMG_0177.jpg

And later I might do this sweet trash can mod. :)

http://forum.grrrr8.net/showthread.php?t=1324

[SRG963]

Looks GRRRR8!

I would also recommend the LPM and a HSRK from VMS.

[norm8332]

Nice Job! Looks good. Where did you get the pipe?

[TurboMatt]

Thanks! :cheers:

Definitely plan on picking up the HSRK, and I've already opened up the LH grille to let air into that area.

I got the bend from Columbia River Mandrel Bending, eBay username mandrel-bends.

[Devilish34]

Awesome looks a lot like the NEP side mount just $130 cheaper and the satisfaction you got from building it yourself. Now go make some more and sell them for 220 plus shipping lol

[stryker g8gt]

Looks good......I should have stuck with my homemade CAI also.......as I have had to reinforce the front nozzle of my Vararam, and watch my IAT temp quickly climb on slow streets, even with the HsrK.

[Seattle09GT]

Did you consider insulating the intake you made? Does the metal trap/absorb heat?

[GT-610]

good work...I did the same thing for my Grand prix!

[TurboMatt]

good work...I did the same thing for my Grand prix!

:headbang:

[TurboMatt]

Did you consider insulating the intake you made? Does the metal trap/absorb heat?

Yeah, everything in this area gets really hot, and I did consider doing that, and even looked at a few different insulating wraps while I was thinking about this project. But from the little I know about heat transfer, I'm betting the amount of heat picked up through this short intake tract will be minimal. Plus it looks way cooler all shiny and stuff.

Of course, I reserve the right to change my mind at any time. :banana:

[todds87ss]

And later I might do this sweet trash can mod. :)

http://forum.grrrr8.net/showthread.php?t=1324

My thoughts exactly! this looks like my revision 1. Finally got tired of the look and went with RF with HSRK. Final pics are in DIY update thread. I always applaud anyone doing their own fab work. Keep on laying the ground work for the rest of us!

[uh6tdrvr]

very nicely done!

[NickelnDime]

Lookin' good!

['02 ws6]

Nice work! Looks very clean. Good ingenuity you got going there.

[TurboMatt]

Thanks, guys! I finally got around to putting the foam tape on the frame yesterday. Also put a little piece on the washer fluid fill tube because apparently it was making intermittent contact.

Still looks good, and I love the way it sounds under WOT. :headbang:

[Shneaky]

Wanted to say thanks for this GRRRR8 write-up! I used your plans and fabbed up a very similar setup just last weekend. I was very surprised that I could actually feel a difference, and I really like the growl and high pitched wooshing noises coming from under the hood now.:woohoo:

Did you do battery disconnect/relearn? And also, have your mpg's changed at all? Mine shot down a bit, but I am willing to bet it is due to Lead-Footerson's Syndrome. :thumbsup:

[-Ray-]

Wanted to say thanks for this GRRRR8 write-up! I used your plans and fabbed up a very similar setup just last weekend. I was very surprised that I could actually feel a difference, and I really like the growl and high pitched wooshing noises coming from under the hood now.:woohoo:

Did you do battery disconnect/relearn? And also, have your mpg's changed at all? Mine shot down a bit, but I am willing to bet it is due to Lead-Footerson's Syndrome. :thumbsup:

Bring your G8 by the suds on saturday so I can see it. :)

[Shneaky]

Bring your G8 by the suds on saturday so I can see it. :)

Might just have to take you up on that. My parents are in town from Tulsa, and my Dad was the one who passed me the "car guy" genetics. :)

My car might get a bit of a modding inferiority complex though. :(

[-Ray-]

Might just have to take you up on that. My parents are in town from Tulsa, and my Dad was the one who passed me the "car guy" genetics. :)

My car might get a bit of a modding inferiority complex though. :(

I understand. Parshooter was there last weekend and parked next to me. His is stock, and people walked past his car to look at mine for several hours. It was embarrassing. :)

[polo]

Wanted to say thanks for this GRRRR8 write-up! I used your plans and fabbed up a very similar setup just last weekend. I was very surprised that I could actually feel a difference, and I really like the growl and high pitched wooshing noises coming from under the hood now.:woohoo:

Did you do battery disconnect/relearn? And also, have your mpg's changed at all? Mine shot down a bit, but I am willing to bet it is due to Lead-Footerson's Syndrome. :thumbsup:

Do you have pics of your CAI?

[Project Whiplash]

Very nice job on this and great write up.

I really like the looks of that. And the fact that its DIY and it can be a customized i like that. I just got my pipe today from CRMB already had the other items picked up. Im gonna be usen black silicone couplers an painting mine white to keep with my black and white thyme of my car. Ill post pics when i install it tomorrow..

[Shneaky]

I'll get some pics up tomorrow, way too busy tonight. :hang: Still need to paint mine, and I ordered Red couplers on Ebay and somehow got blue. But, I tried them out and liked the color. Doesn't match the red Cone filter, but it is buried so deep in the front corner you can barely notice that the filter is red. So, mine will look almost exactly like TurboMatt's original, but on a MGM G8.

[mot76]

Where was your MAF sensor harness routed with the stock setup? Was it under the power steering hoses or do you have it between them? I noticed mine was rubbing on my drive belt, so, I rerouted it between my power steering hoses. This was, of course, with the stock airbox setup, that I noticed this. Is everybody else's routed that way, too? Or, my MAF sensor was not properly postioned, causing the wire to hang lower? I don't know.

[bobyoung]

Great job! Looks like a pro job.

[Old Cop]

Ka-bump. I'd like to keep this one alive for awhile.

[Project Whiplash]

Got mine done looks great sounds good too. do i need too disconnect battery/relearn? i didnt end up painting mine i like the SS look i might polish it over the winter. I post pics of mine tomorrow..

[Shneaky]

Wow, forgot to upload pics here after that last post. Here are a few (crappy lighting). And, yes, I will be cleaning that dirty engine bay with some Simple Green tomorrow after looking at these pics. :nah:

Still no codes, noticeable power, and a wonderful growl. Turbomatt, does yours make a high-pitched whistling/wooshing noise from like 1500-2000 rpms? Mine sounds almost like a small turbo spooling.....which I believe is the big-old cone filter sucking air at a certain velocity, but I wanted to make sure it wasn't an air leak along the intake tract somewhere.

http://i137.photobucket.com/albums/q218/cowboyplanet/G8/102_3751.jpg?t=1254033633

http://i137.photobucket.com/albums/q218/cowboyplanet/G8/102_3756.jpg?t=1254033673

http://i137.photobucket.com/albums/q218/cowboyplanet/G8/102_3757.jpg?t=1254033817

[dulvalius]

So would it be a safe bet to buy 2 4.0 inch to 3.75 for the maf in and out or just one 4" to 3.75 for the maf out? Or just stick to the 4 inch couplers?

[Shneaky]

The Spectre filter I used came with multiple sizes of rubber spacers, so I simply squeezed one inside the 4" hump coupler for the MAF out to reduce the size. The inbound seems a little bigger and I just tightened down a 4" coupler, no reducer. So all 3 of my couplers were 4" only. Seems to work just fine, but a reducer might be a tad bit cleaner look and better fit without having to tighten the SS clamps as much.

[dulvalius]

ok ill try one reducer then for the "out" and tightened down the 4.0 for the "in" like you did....I prob will be buying a universal cone style like yours but may not have the spacers.

[Parja]

TurboMatt, I was looking on eBay and I think I found the same tubing that you used. Did you buy the mild steel tubing? If so, you're probably going to want to paint or otherwise seal the inside of your tubes or they're going to rust. I don't think your engine is going to like sucking in flecks of rust.

[Shneaky]

TurboMatt, I was looking on eBay and I think I found the same tubing that you used. Did you buy the mild steel tubing? If so, you're probably going to want to paint or otherwise seal the inside of your tubes or they're going to rust. I don't think your engine is going to like sucking in flecks of rust.

I believe he got the same pipe as I did; which is Aluminized Steel. It is rust resistant until the aluminized coating wears off, which I assume will be a long while inside a clean intake tract. I will keep an eye on mine though. :)

[dulvalius]

I finally got mine done today...Nice little weekend project. I ended up color matching mine to my paint code , Here are the results:

4004

4005

4006

[Shneaky]

Nice work! :flame:

[dulvalius]

thank you sir

[Shneaky]

Question for the experts....

There are a handful of us with these cutom homemade setups running around. I am VERY happy with mine so far, seems to breathe very well. My only worry is all the talk of hydrolock when modifying the intake.

Is this setup likely to ever hydrolock??

It reaches down decently far into the fenderwell, but it has a very long tract. I assume that driving through 2 feet of water could turn my setup into a engine-straw, but normal driving with some puddles and rain?!?! Any chances that simple splashing and spray getting into the area could make the filter wet enough to hydrolock?

Here is what our setups probably look like with the front off for fenderwell reference...(Mine is probably about 4-6 inches shorter into the fenderwell.)

[GRRRR8]

Not gonna happen. You would have to drive through some pretty deep water to have any issues.

[todds87ss]

Question for the experts....

There are a handful of us with these cutom homemade setups running around. I am VERY happy with mine so far, seems to breathe very well. My only worry is all the talk of hydrolock when modifying the intake.

Is this setup likely to ever hydrolock??

It reaches down decently far into the fenderwell, but it has a very long tract. I assume that driving through 2 feet of water could turn my setup into a engine-straw, but normal driving with some puddles and rain?!?! Any chances that simple splashing and spray getting into the area could make the filter wet enough to hydrolock?

Here is what our setups probably look like with the front off for fenderwell reference...(Mine is probably about 4-6 inches shorter into the fenderwell.)


The background: Several LS1 powered camaros hydrolocked due to cold air (FTRA) setups. Driving through deep puddles at anything more than an idle caused water to be ingested by the intake system.

This relates to our setups in a very small way. IF you have a system that is sealed to the lower fascia, and you immerse it under water, you could draw water into the intake. None of the aftermarket systems are sealed to the lower fascia. For the RotoFab systems, if you submerge the end of the snorkle, you take a chance on drawing water up into the intake. Seems like thats about 18 inches. Most folks will never worry about it.

[dulvalius]

They way the OP made the instructions on how to DIY this intake, I dont think we are gonna have a prob. Your filter sits alot lower into the fender well then mines does. If you leave the bottom front facias alone (without cutting the bottom open for more air mod) I wouldnt worry about it.

[Shneaky]

Yeah I hadn't planned on doing either of the variations of the LP Mods due to the filter being exposed down into the fenderwell. But, I am very glad to know I don't really have anything to worry about aside from 2 foot deep puddles.

Thanks for the info guys, GRRRR8 forums to the rescue again! :woohoo:

[TurboMatt]

It's been a long time since I poked around the forum, and I see several questions were posted. Here are my answers:

Mileage is about the same. I have kept records of my mileage for almost every tank of gas since I bought the car at the end of May. I am getting around 16-17 around town, 22-23 on the highway (75-80 mph) and that's with a pretty heavy foot and a few WOT blasts every now and then.

No, I didn't disconnect the battery to reset the computer, but that's not a bad idea. I did notice it seemed to lean out at the top of first gear before the computer learned things had changed. That was with both the stock and Superchips tunes. I'm now running one of Superchips' CAI tunes... can't remember but I think it's the Volant. I sort of plan to try them all but it's running fine right now so I'll probably procrastinate. :)

Yes, mine makes a very slight whistling noise in the lower rpm range.

Yes, I used mild steel tubing but, as someone else mentioned, it's aluminized. I do plan to keep an eye on it though. I used some similar tubing for intercooler piping on my GN. It's been on there over 10 years and so far no rust. Of course it's after the turbo so it's a little different application.

I am kinda leery about hydrolock, since I have the LP mod, and a friend recently broke a rod in his LS1 Trans Am due to hydrolock. I actually diagnosed it. It was a sick feeling to turn the crank with a wrench and just feel it lock up solid at a particular angle. Confirmed it by looking into the cylinder with a borescope -- turned the crank back and forth and the piston didn't move. :hang: Anyway, I just plan to do my best to be careful.

Thanks guys!

[Shneaky]

Good to hear yours is running strong too!

Thank again for the inspiration to build, always more fun that way.

[speedisking]

This is a great looking CAI and the price is reasonable. Thanks for posting it. I plan to build one and I will post pics when its done.

[RamJet]

Can this mod be done with aluminum tubing instead?

It looks good, and the price is nice, I may have to give it a try either way.

[TurboMatt]

I don't see why not. In fact, I'm not sure why I didn't do that in the first place!

[Mjakaz09GXP]

Thanks for this TurboMatt!! I Just ordered all my parts from silicon intakes dot com. I got the aluminum tubing tho. Should have everything this week.

[hayabusa160]

should add a velocity stack to the end of it with a 6 inch filter it should sound real nice and flow real good. im tempted to try this but i have a roto fab already.

[speedisking]

Thanks for this TurboMatt!! I Just ordered all my parts from silicon intakes dot com. I got the aluminum tubing tho. Should have everything this week.

I am having a hell of a time finding that U bend in mild steel. The guys at Columbia River are not going to be bending 4" for another couple weeks and thats what they told me a couple weeks ago. I have searched the internet high and low to find anyone else bending that radius in a 4" pipe and there just aren't any. I was thinking about ordering the 6061 aluminum pipe from Accel Tube, its about $10 more but I have some concern about heat soak. Will the aluminum heat up faster or retain heat longer than mild steel? If it does then it kinda defeats the whole point. I am sure it will increase air velocity and eliminate a lot of the turbulence and restriction but what about heat?

What are everyones thoughts on 6061 vs mild steel?

http://www.acceltube.com/mm5/merchant.mvc?Screen=PROD&Store_Code=acceltube&Product_Code=FAB-400ALM-6061-180DEG&Category_Code=ALM

[Scott]

http://www.acceltube.com/mm5/merchant.mvc?Screen=PROD&Store_Code=acceltube&Product_Code=FAB-400ALM-6061-180DEG&Category_Code=ALM

If you end up going with the 6061: clicky (http://www.siliconeintakes.com/product_info.php?cPath=19&products_id=777&osCsid=3f218177b625c99e53cad9abe22e3ac3)

[stlG8]

... I was thinking about ordering the 6061 aluminum pipe from Accel Tube, its about $10 more but I have some concern about heat soak. Will the aluminum heat up faster or retain heat longer than mild steel? If it does then it kinda defeats the whole point. I am sure it will increase air velocity and eliminate a lot of the turbulence and restriction but what about heat?

What are everyones thoughts on 6061 vs mild steel?


I used TurboMatt's outline for an Aluminum CAI about a year ago and it works great. IMO, any metalic CAI will heat soak, but with Aluminum, the material will lose the heat very quickly when you hit the gas.
Last July, I had a friend check my AIT's. When at a stop light at it was over 115, IIRC - but when I gased it - the temps dropped like a rock to the mid to high 90's.
The intake sound is great and helps make the car more responsive. I'll try to post some picks later.
Good luck!

[Daniel Linnett]

any maggie cars try to make this work? I have RotoFab with the Magnuson plastic tubing. I would like to get as much air to my blower as possible.

[speedisking]

Has anyone with turbomatt's CAI installed the HSRK on it? I finished the intake today but I am not sure the best place to locate the hsrk . It seems as far before the MAF in the intake would be best but where?

edit: Also anyone running a turbomatt CAI and a Cortex? What tune seems to work best?

[MFE]

Man, inflation is a bugger. I have this all spec'd out at Summit and my cart is $227.42 before "handling".

[seahawksax]

what do your IAT's look like with that. i would think that they would be higher because of it being made out of metal

[Nu Jersey Devil]

i would like to know as well.

[gr8lover]

what do your IAT's look like with that. i would think that they would be higher because of it being made out of metal

And its not sealed off or anything.....

[-Ray-]

what do your IAT's look like with that. i would think that they would be higher because of it being made out of metal

There is a lot more going on than one would think. First off, you need to know the thermal coefficient of each material. Some materials dissipate heat much faster than others. Then you need to know the incoming air temperature. A true cold air intake does just that. The incoming air must be colder than what is under the hood. BTW, the stock intake is a CAI because of where it is located for the air charge.
So, ok, the inlet is getting the coldest air possible. It has to transfer through something to get to the intake manifold. Both plastic and steel/aluminum pipes sit above a radiator hose getting hot. How they release the heat is their thermal coefficient. The inside of the pipe is insulated from heat exchange by the velocity of the incoming air. Down near the pipe, it's a different story. There will be a thermal barrier where the air is heated. So were all concerned about the air charge temp, but if we ignore the intake air temperature sensor then all of this is a moot point.
We all know that colder air is better for making more horse power. Inside the MAF is the IAT sensor. It measures the air temperature. When the temp exceeds a preset value, the ECM removes timing. In effect, the MAF being heat soaked is more important than the actual air charge in this case. We've seen cases of cars intake air temp exceeding 120 degrees, but the ambient temp is only 80. Install a HSRK and we can see IAT's in the low 80's.