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prophet513
08-23-2011, 03:09 AM
Okay this may be a big thread or it may have one simple answer. I was thinking about making a custom air intake as a small project for my Celica as I wait for the bigger projects to get started.

Back when I had my MR2 I ordered an intake off Ebay. Basically just gave the car a MUCH LOUDER sound.

I was wondering what all is behind the sound of an air intake, not trying to have a ricey sound, just something different. My MR2 sound was much too loud for my goals with my Celica.

Basically I guess I want to know if its all in the shape or size of the filter or if part of it is the passage from the filter to the engine? If it isn't just the filter, then what size piping does what? Does it depend on angles or curves? Or maybe its NOTHING like that at all. If it IS however the filter, what shaped filters do what, and does that vary by size?

My project would be simply for my auto 90 ST. But I'm completely open to all other set ups or input, especially if anybody else has made any custom air intakes for their cars. As always, I love pictures.

temperacerguy
08-23-2011, 03:18 AM
the sound you're hearing, is the sounds coming from your intake manifold resonating and being amplified down the pipe. Those big chambers that are attached to the factory intake are designed to cancel out the resonance.

KoreanJoey
08-23-2011, 03:18 AM
Construction is one of the biggest ones. Anything aluminum really seems to resonate loudly. How loud is loud though?

prophet513
08-23-2011, 03:21 AM
by chambers you mean basically like the box and all other big non metal pieces?

And yeah good question on being too loud. I don't know. Too loud to hear people or music in my car and don't want it to sound like its right next to me when its 100 feet away. I was thinking about lightweight metals though, which now sounds like a bad idea. Because of course it would be good to lose a little weight in the process.

prophet513
08-23-2011, 03:31 AM
and would a shorter pipe make a quieter sound? I wish there was a diagram for this ha

KoreanJoey
08-23-2011, 03:37 AM
There are a LOT of factors. Mostly it'll be the material it's constructed with, the length/volume and the filter used.

prophet513
08-23-2011, 03:41 AM
There are a LOT of factors. Mostly it'll be the material it's constructed with, the length/volume and the filter used.

can you elaborate a little on the role of those factors?

Doowstados
08-23-2011, 04:15 AM
can you elaborate a little on the role of those factors?

I swapped from a longer CAI to a short ram because my CAI got a crack in it. They were both made from the exact same parts, all aluminum. Standard cone shaped filter. The short ram is much louder at high RPMs (deeper sounding as well). I'll also say that my CAI was moved to several different positions with different curves and sounded the same so bends are not a factor in the sound pre-manifold. The "sucking" noise is much louder with the short ram as well.

If you want to hear an interesting noise, try a throttle body spacer.

prophet513
08-23-2011, 04:23 AM
Doowstados - any way I can see a video or anything?

KoreanJoey
08-23-2011, 04:26 AM
I'd fire up my blacktop and let you listen but I'm pretty sure my neighbors would stab me. Maybe tomorrow.

jaydog82
08-23-2011, 04:46 AM
i have found that the short ram intake are much to loud for my taste, i loved my 3in aluminum cold air intake routed into the fender with an aem dry-flow filter. It was on my 90 gt and i would go with a smaller pipe ID for a ST, maybe 2.25 or 2.5 max.
http://carphotos.cardomain.com/ride_images/2/4955/261/24885130445_medium.jpg

temperacerguy
08-23-2011, 07:47 AM
OK, here are only some of the factors that affect the sound from the intake:

Length
Curves
Diameter
Material
surface finish in the pipe
any impedances
the type and length of the coupler
the diameter difference between the throttle body and the intake pipe
The throttle opening
the camshaft profile
the camshaft timing
the filter media
the filter shape
the filter frame
where you have the air temp probe
how the pipe is mounted to the frame

and a million other minute details...

temperacerguy
08-23-2011, 07:51 AM
My recommendation is for you to do about 2 years of fluid dynamics classes... then you would be able to calculate the best flowing yet noise canceling intake.

prophet513
08-23-2011, 02:44 PM
There's so much I don't know... But its good to learn that. I may just try a few different things and if nothing works then go back to the stock intake if anything.

KoreanJoey - What did you put your blacktop in? Thats the engine I'm hoping to drop in my Celica after my 4afe is no more.

Doowstados
08-24-2011, 01:40 AM
http://www.youtube.com/watch?v=n8mNo9_hzQ4&feature=related

Here's an okay video of a throttle body spacer whistle. You can find short ram sounds all over youtube.

KoreanJoey
08-24-2011, 05:16 AM
There's so much I don't know... But its good to learn that. I may just try a few different things and if nothing works then go back to the stock intake if anything.

KoreanJoey - What did you put your blacktop in? Thats the engine I'm hoping to drop in my Celica after my 4afe is no more.

AE86.

Currently running stock motor w/ T3 velocity stacks, silkroad high-rise header, FuelAirSparkTechnology ECU putting 164rwhp @ 8400

prophet513
08-24-2011, 02:24 PM
http://www.youtube.com/watch?v=n8mNo9_hzQ4&feature=related

Here's an okay video of a throttle body spacer whistle. You can find short ram sounds all over youtube.

thats definitely a weird sound...

KoreanJoey
08-25-2011, 11:56 PM
LOL

http://www.youtube.com/watch?v=ZTkVLMxToUE

prophet513
08-26-2011, 02:09 AM
Ha that one sounds good but for the volume settings my speakers are on its pretty ridiculous ha.

All I remember was my MR2 just being insanely loud and deep from a GIANT parking lot's length away. I was surprised when I first heard it from the outside.

By the way, whered you get your blacktop?

KoreanJoey
08-26-2011, 06:06 AM
I actually got it off craigslist...

prophet513
08-26-2011, 02:02 PM
thats not bad though ha I know somebody with 2 cars from craigslist.

any clue how many miles it had and how many miles have you put on it?

KoreanJoey
08-26-2011, 07:04 PM
No idea, and I haven't put many. I've been busy with building the chassis.

temperacerguy
08-26-2011, 10:34 PM
I love the AE86 chassis. built a 7A-FTE for one about 8 years ago. it's just "tossable"

KoreanJoey
08-27-2011, 02:27 AM
Something about 2k lbs cars are just awesome.

temperacerguy
08-27-2011, 02:56 AM
Something about 2k lbs cars are just awesome.

True, another fun car is the EG civic. I am highly considering building a track EG for the hell of it.

KoreanJoey
08-27-2011, 03:02 AM
I'm actually packing right now to fly out to Lincoln, NE to race an EK Si @ Solo Nationals. Should be good fun.

They'll be streaming it live via UStream.

prophet513
08-27-2011, 04:53 AM
True, another fun car is the EG civic. I am highly considering building a track EG for the hell of it.

WISH i could even just say that about my Celica. I'm poor

temperacerguy
08-27-2011, 07:58 PM
I'm actually packing right now to fly out to Lincoln, NE to race an EK Si @ Solo Nationals. Should be good fun.

They'll be streaming it live via UStream.

Good luck, I used to run an MR2 Turbo in AS about 15 years ago... It's funny that I regretted getting a turbo at the time as the non-turbos were more competitive in CS.

I built an engine/tranny combo for a customers EK about 6 years ago. It was a B20 with CTR head, eagle crank and rods, JE pistons, and all the bells and whistles... That was the car that made me realize how simple "pick and match" parts for a honda was.. I found building them so easy that I was custom fabricating things just to make it feel like I was making something custom.

KoreanJoey
09-06-2011, 02:42 AM
Dude, it's not hard for a toyota either... well, crank is difficult but most everything else is just measured up to spec.

Probably a bit more costly but probably not as much as most people think.

temperacerguy
09-06-2011, 02:51 AM
I've built MANY MANY MANY toyota Engines.... but there is no where near the selection and availability of aftermarket components for a Toyota, compared to Hondas.

KoreanJoey
09-07-2011, 02:07 AM
Don't look at an item description and order via measurements. Viola.

temperacerguy
09-07-2011, 02:16 AM
OK If toyotas are so easy to do... find me a set of QUALITY H-beam rods for a 7A.


It took me 4 days, and calls to 5 different manufacturers before I found a rod CLOSE to what I needed. The big end needed to be milled down on both sides to fit the crank journals, the crank rod journals needed to be turned down slightly to accept the rod and the wrist pin needed to be moved up in the piston to get the right compression height.

Oh... and the Rod we ended up using was designed for a Honda.... a B series I believe.

CollapsedNut
09-07-2011, 02:56 AM
Back on topic. I hear PVC is much quieter then metal for CIA's.

prophet513
09-07-2011, 03:01 AM
Back on topic. I hear PVC is much quieter then metal for CIA's.

Makes tons of sense! It may be a tad heavier though right?

And I'm guessing it can stand the heat from the engine bay right? People use PVC for potato guns...

temperacerguy
09-07-2011, 03:31 AM
I've made CAIs from carbon fiber sleeve. It's very easy to do so. and as quiet as PVC tube (doesn't resonate like AL)

Run a alluminum bar down the center of a pool noodle.

Bend the noodle/bar into the shape you want the piping. with 6"s of the bar sticking out each side.

Slide 2-3 carbon fiber sleeves over the noodle.

wet the sleeves out with Resin (Epoxy Resin, not polyester!!!)

Wrap assembly with plastic wrap

Let cure for 24 hours.

Remove plastic wrap

Remove noodle (rip out what you can, disolve the remainder with acetone)

Trim edges, and you have a shaped carbon fiber tube.

The assembly can be as elaborate or as simple as you want it to be. Once you get good, you can glue 1/2" foam tubes cut in half around the noodles at the ends of the shapes... This will cause the final CF tube to have a bead in it so your couplers won't slip off. If you will be using these for Turbo pipes, I recomend making them stronger with more layers and a vacuum baged assembly, but for simple intakes, a few layers in a standard layup would be fine.

KoreanJoey
09-07-2011, 07:04 AM
OK If toyotas are so easy to do... find me a set of QUALITY H-beam rods for a 7A.


It took me 4 days, and calls to 5 different manufacturers before I found a rod CLOSE to what I needed. The big end needed to be milled down on both sides to fit the crank journals, the crank rod journals needed to be turned down slightly to accept the rod and the wrist pin needed to be moved up in the piston to get the right compression height.

Oh... and the Rod we ended up using was designed for a Honda.... a B series I believe.

Who were you talking to? Carillo usually does a real good job of making stuff by spec. My head guy does a lot of really oddball stuff (think like old alfa, triump, v12 jag) and never has not found what he needed. Given, not as easy as ordering stuff from a catalog like all the honda stuff BUT building and fabricating race suspension parts has really opened my eyes as to how much cheaper it can be sometimes to get your own stuff made.

IE: Piston, there are really only one or two places that make the piston forgings (at least here in the US). The piston manufacturers buy those forgings and machine them to whatever they want them to go in.

KoreanJoey
09-07-2011, 07:05 AM
I've made CAIs from carbon fiber sleeve. It's very easy to do so. and as quiet as PVC tube (doesn't resonate like AL)

Run a alluminum bar down the center of a pool noodle.

Bend the noodle/bar into the shape you want the piping. with 6"s of the bar sticking out each side.

Slide 2-3 carbon fiber sleeves over the noodle.

wet the sleeves out with Resin (Epoxy Resin, not polyester!!!)

Wrap assembly with plastic wrap

Let cure for 24 hours.

Remove plastic wrap

Remove noodle (rip out what you can, disolve the remainder with acetone)

Trim edges, and you have a shaped carbon fiber tube.

The assembly can be as elaborate or as simple as you want it to be. Once you get good, you can glue 1/2" foam tubes cut in half around the noodles at the ends of the shapes... This will cause the final CF tube to have a bead in it so your couplers won't slip off. If you will be using these for Turbo pipes, I recomend making them stronger with more layers and a vacuum baged assembly, but for simple intakes, a few layers in a standard layup would be fine.

This is ingenious!

Doowstados
09-07-2011, 07:24 AM
I've made CAIs from carbon fiber sleeve. It's very easy to do so. and as quiet as PVC tube (doesn't resonate like AL)

Run a alluminum bar down the center of a pool noodle.

Bend the noodle/bar into the shape you want the piping. with 6"s of the bar sticking out each side.

Slide 2-3 carbon fiber sleeves over the noodle.

wet the sleeves out with Resin (Epoxy Resin, not polyester!!!)

Wrap assembly with plastic wrap

Let cure for 24 hours.

Remove plastic wrap

Remove noodle (rip out what you can, disolve the remainder with acetone)

Trim edges, and you have a shaped carbon fiber tube.

The assembly can be as elaborate or as simple as you want it to be. Once you get good, you can glue 1/2" foam tubes cut in half around the noodles at the ends of the shapes... This will cause the final CF tube to have a bead in it so your couplers won't slip off. If you will be using these for Turbo pipes, I recomend making them stronger with more layers and a vacuum baged assembly, but for simple intakes, a few layers in a standard layup would be fine.

I think I may try this. Happen to have any pictures of what the final product looks like? How stiff is it when it drys?

temperacerguy
09-07-2011, 02:01 PM
Who were you talking to? Carillo usually does a real good job of making stuff by spec. My head guy does a lot of really oddball stuff (think like old alfa, triump, v12 jag) and never has not found what he needed. Given, not as easy as ordering stuff from a catalog like all the honda stuff BUT building and fabricating race suspension parts has really opened my eyes as to how much cheaper it can be sometimes to get your own stuff made.

IE: Piston, there are really only one or two places that make the piston forgings (at least here in the US). The piston manufacturers buy those forgings and machine them to whatever they want them to go in.

Carillo, Eagle, weisco, cosworth, I don't remember who else... Typically you can get close with theire rod forgings, then machine to what you need (like what we did), but you go from a $300 set of rods sitting on a shelf, to a $700 set of rods that takes 3 weeks. Then from the custom rods you have, the pistons need to be custom machined so a $300 set of shelf pistons becomes a $480 set of pistons (JE does all of my pistons, and the 3S 2.2 shelf pistons they carry are from the pistons we designed and speced out back in 97), and JE's turnaround is not lightning fast at 2-6 weeks depending on the season, then the crank needs to get turned, so a simple polish/balance job becomes a custom grinding/polish/balance job... (when I can buy a completely finish machined Eagle B18 or B20 crank off the shelf for less money)

So, I can either buy shelf items for a honda and spend $1200 on short block work for a 400hp capable block, or spend close to $2000 for a comperable A series.

temperacerguy
09-07-2011, 02:07 PM
I think I may try this. Happen to have any pictures of what the final product looks like? How stiff is it when it drys?

No, I am a neophite when it comes to cameras.... I still use a 1960s steel bodied cannon F body, and use it only on the Fiance' and kid. The stiffness of the final product is dependant upon the layers of carbon fiber, and how thick the tow is, as well as the type of resin. if you use 4 layers, a quality resin, and vacuum bag it, it's as strong as steel.

KoreanJoey
09-08-2011, 07:30 AM
Carillo, Eagle, weisco, cosworth, I don't remember who else... Typically you can get close with theire rod forgings, then machine to what you need (like what we did), but you go from a $300 set of rods sitting on a shelf, to a $700 set of rods that takes 3 weeks. Then from the custom rods you have, the pistons need to be custom machined so a $300 set of shelf pistons becomes a $480 set of pistons (JE does all of my pistons, and the 3S 2.2 shelf pistons they carry are from the pistons we designed and speced out back in 97), and JE's turnaround is not lightning fast at 2-6 weeks depending on the season, then the crank needs to get turned, so a simple polish/balance job becomes a custom grinding/polish/balance job... (when I can buy a completely finish machined Eagle B18 or B20 crank off the shelf for less money)

So, I can either buy shelf items for a honda and spend $1200 on short block work for a 400hp capable block, or spend close to $2000 for a comperable A series.

I like JE but yeah, they take a while, and charge extra... Try Ross pistons. No problem getting custom pistons machined and at least the last time they didn't charge any "CUSTOM" fee.

http://www.rosspistons.com/products/index.php#cid=3&acc_id=0&type_id=33&vehicle_id=0