maf and throttle body diameter

[AndyA6]

Originally Posted by Bfan

I have a G-meter that measures 0-62 mph among other things. It used to give me 5.8 sec average of several runs before mods on my '01 S. I now get 5.2 sec average after modding. From what I have found out on the net this means that my max HP was 250 (figures), and is now 285.

My mods are Fabspeed catless headers, 997 plenum, 74 mm TB, and desnorkel.

So I am really happy and I have this thread and all the fine members of this forum to thank...

Very nice! Thank you for your feedback.

Again, mine is running perfectly ok as well.

[Homeboy981]

Here's a pic or two. Will have to compile parts list.

You start with a HUGE CONICAL filter…(this was Stage1-notice MAF is by the filter)


Then move the MAF so that it is practically sitting on the Throttle Body (Stage2) - using the Honeycomb to straighten the airflow before the MAF & TB.


It is 4" until it drops to 3.5" at TB.

Enjoy! I sure am!

[The Radium King]

homeboy - do you have that filter enclosed yet? otherwise it's drawing hot air from the engine compartment. I did a quick search and here's some math for you:

http://www.mazda3club.com/showthread.php?t=18386

[The Radium King]

cool with the half second increase in zero to 60 times. also like the idea of filing the TB; the 1/8" lip on that thing always seemed wrong to me.

[Ckrikos]

Can I ask what are you guys using to connect the intake to the TB? Is there a better option than the flexible hose? I found one on eBay but the guy wants like $250 for a piece of plastic.

[Homeboy981]

Here is how close my MAF is to the Throttle Body…


Using the Honeycomb filter to straighten the airflow prior to hitting the MAF.
Here is a shot of that:


@TRK - you got me! No cold air…yet! I have a couple prototypes, like this one….


Trying to take advantage of the conical shape of the filter.. May have to use a box…the cone thing isn't working. The open end of the cone presses against the firewall for a "sealed" fit.

Here's another view of the HUGE cone intake (HINT: It barely clears the engine bay getting it in)…


Another view standing up….


From the inside...


It still has to be painted, but the design is not perfected….I may regret this but…any suggestions?

[Homeboy981]

Originally Posted by Ckrikos

Can I ask what are you guys using to connect the intake to the TB? Is there a better option than the flexible hose? I found one on eBay but the guy wants like $250 for a piece of plastic.

Siliconintakes.com has them in a bunch of sizes and flavors. Don't buy that thing on ebay…I have seen it - you CAN DO better.

[The Radium King]

crikos - I bought a 3.25" to 3" reducing 90 degee elbow. 3.25" over the tb and reduces to 3" at the bend. this allows a fit to the 3" maf housing (or whatever combo of 3" couplers and joiners you use to get to the maf housing); it also provides more clearance from the back of the engine bay.

homeboy - pretty tight in there, huh? i'm currently using the larger of the bmc air boxes with a 3.25" filter. even that doesn't fit well. I bet 4" is tight. one thing that will gain you some room is to remove the insulation on the inside of the engine bay on that side - should buy you 1/2" or so.

another option might be to not mount the filter in parallel with the engine, but rather have the piping do a 90 degree turn into the actual side intake and mount the filter element in the fender well. they are doing this on caymans with a kit from fabspeed:

BGB / Fabspeed Cold Air Intake Install (with Pics) -

you would still probably have to go with a smaller filter, however; I think there would be room in the fender well, but the opening into the engine bay is only *i think* around 3.5".

otherwise, i think you could diy something similar very easy: remove the rubber liner in the fender well, trace the inside flange onto a piece of lexan, drill a 4" (or whatever) hole in it, bolt it in place, mount the air filter through the hole and connect the piping.

[Wret]

Where did this filter box come from?

[Homeboy981]

Originally Posted by Wret

Where did this filter box come from?

Nice! But I would move that MAF closer to the TB….you will be impressed by the better readings. I thought is was hooey at first, but cannot deny the results now!

Also, that is a small filter and it does not have a filter element in the FRONT of the the filter…that is what I was looking for. I just got a JUMBO sized filter - maybe a little too big but I live in Texas, so it is expected!

[jacabean]

real nice set up here .

Originally Posted by Wret

Where did this filter box come from?

[Alpine003]

For guys wanting a slight increase without the hassles of changing out plenums, I'm selling a bored OEM TB as I got the wrong one for my Carrera.

http://986forum.com/forums/boxster-parts-sale-wanted/44822-fs-bored-oem-egas-throttle-body.html#post337821

[Homeboy981]

Originally Posted by The Radium King

homeboy - pretty tight in there, huh? I bet 4" is tight. one thing that will gain you some room is to remove the insulation on the inside of the engine bay on that side - should buy you 1/2" or so.

another option might be to not mount the filter in parallel with the engine, but rather have the piping do a 90 degree turn into the actual side intake and mount the filter element in the fender well. they are doing this on caymans with a kit from fabspeed:

otherwise, i think you could diy something similar very easy: remove the rubber liner in the fender well, trace the inside flange onto a piece of lexan, drill a 4" (or whatever) hole in it, bolt it in place, mount the air filter through the hole and connect the piping.

TRK,
4" is VERY TIGHT! In fact, I hate taking it apart because my hands get mangled! I have not resorted to removing the insulation. However, the insulation does deform a little where the intake resides against it.

One of our members has a design that "turns" into the hole in the side of our car....but he said it came at a cost. He had to 'hollow out' part of the passenger area and the noise came in too. Besides, making that 90 degree turn would certainly cause more air turbulence and reduce the overall airflow somewhat...but it would be a 100% Cold Air Intake.

I thought of Lexan too, but the engines temps preclude me from using it. It is just too hot in the engine compartment. I have a bunch of Lexan, plex, etc. laying around from designing Hydrogen units but the temps would be too high for that application. Nothing would be worse than running a day at the track and finding a melted mess of plastic in the engine bay!

Also, I am trying to select a material that can be molded or can be used without square edges - so as not to disrupt the airflow coming in. I have a metal "square box" but am just not happy with how it is finished out....but I guess it IS BETTER than nothing! Especially, based on your calculations, that I am Losing HP running warmer air.

Where did that Cold Air Filter box come from? Was it customer-made? Out of what?

[jacabean]

look into making a mold of your air box out sheet foam and clay . then you can make a mold out of that . epoxy resin and glass mat would be a good choice of materials.

Originally Posted by Homeboy981

TRK,
4" is VERY TIGHT! In fact, I hate taking it apart because my hands get mangled! I have not resorted to removing the insulation. However, the insulation does deform a little where the intake resides against it.

One of our members has a design that "turns" into the hole in the side of our car....but he said it came at a cost. He had to 'hollow out' part of the passenger area and the noise came in too. Besides, making that 90 degree turn would certainly cause more air turbulence and reduce the overall airflow somewhat...but it would be a 100% Cold Air Intake.

I thought of Lexan too, but the engines temps preclude me from using it. It is just too hot in the engine compartment. I have a bunch of Lexan, plex, etc. laying around from designing Hydrogen units but the temps would be too high for that application. Nothing would be worse than running a day at the track and finding a melted mess of plastic in the engine bay!

Also, I am trying to select a material that can be molded or can be used without square edges - so as not to disrupt the airflow coming in. I have a metal "square box" but am just not happy with how it is finished out....but I guess it IS BETTER than nothing! Especially, based on your calculations, that I am Losing HP running warmer air.

Where did that Cold Air Filter box come from? Was it customer-made? Out of what?

[Homeboy981]

O.K. I have this mold, now what?

Beside car...


Closeup of Side Intake...


Side of the Side?


As it would sit in the Engine Bay...


Even made it flanged, so it could be inserted easily...


Another view of the flange...


Bought the glass, and then ran out of time. Later, I realized it was because Fiberglass is not a skill I posses...anyone can help let me know.

But where DID that OTHER FILTER BOX come from?

[BYprodriver]

[QUOTE=Homeboy981;338164]O.K. I have this mold, now what?



Given the title of the thread you are posting in, start a new thread with the appropriate title.

[Overdrive]

BYProvider, since no one seems to want to answer you, I think I may try. That airbox seems to be the one that comes with something like the few CAIs made for the Boxster. It may very well not be, but that's the first thing that comes to mind for me. Hopefully whoever posted the picture will divulge their source if it isn't a custom part.

[jacabean]

there are some good you tube tutorials for making parts . you should get some info. before you try any glass and resin. Looks like what you have now is called a plug . you need to make a mold out of it with a parting line to create two parts . then with that mold you can make your actual part or parts. research before you even think about doing this .

Originally Posted by Homeboy981

O.K. I have this mold, now what?

Beside car...


Closeup of Side Intake...


Side of the Side?


As it would sit in the Engine Bay...


Even made it flanged, so it could be inserted easily...


Another view of the flange...


Bought the glass, and then ran out of time. Later, I realized it was because Fiberglass is not a skill I posses...anyone can help let me know.

But where DID that OTHER FILTER BOX come from?

[Wret]

Originally Posted by Overdrive

BYProvider, since no one seems to want to answer you, I think I may try. That airbox seems to be the one that comes with something like the few CAIs made for the Boxster. It may very well not be, but that's the first thing that comes to mind for me. Hopefully whoever posted the picture will divulge their source if it isn't a custom part.

I believe the air filter box is sold by these guys:
Gemballa USA

I used to make similar air boxes back in my mitsu eclipse tuning days. I invented the original kabob skewer contour guide.

[Homeboy981]

I got it my Cold Airbox to work! I am using ONLY Cold Air and the FULL WIDTH of the side air duct!

The problem the 'other designs' seem to suffer from, IMHO is that they are taking hot air from the top of the engine bay…where it's the hotter than anywhere (due to heat rising). My Stage 2 design suffered horribly from this dilemma. HOT air = BAD, COLD air = GOOD.

This new design (Stage3) employs a simple 'inverted' cone that is inverse of the Cone Air FIlter. Thereby creating an 'air space' the engine can gulp air from. The Stage3 is held in place by the 'friction seal' against the firewall (I will revise this and make tabs to mount). The ONLY SOURCE for air is the 3"X 5" duct - and it uses the WHOLE thing!

Here is a shot of the engine cavity mold, with the Cold Air Intake mold in place.


Here the airbox is sealing out all the hot air (except this post). Yes, that is duct tape, Needed for this prototype but not used in production.


Here airbox is connected to the 4" silicone tubing.


How the airbox seals up against the firewall.


Here is it in place with NO GAP at the firewall.


TDK, you were right! It makes a HUGE difference between taking "engine warmed air" and the cold air our cars were destined to run on.

This is the third revision of the original design. There will be another that will have "rabbit ears" on it to mount in the engine bay. This is by far the largest air filter that will fit under the hood. It can take a HUGE GULP of air, with fewer restrictions than the factory. Inspired by watching Eric523!

If anyone is interested…I have a mold to make more!