afm and pod filter....

**mrxplode** · 15-02-2006, 07:23 PM

hey guys

just a question i got a pod filter for my 7afe and i just removed the top of the box and screwed the pod on instead, but the afm just hangs at the bottom of the box... the car seems to be running fine but im wondering will the ecu know the change in air flow thus increase performance????

thanks

**mullett** · 15-02-2006, 11:18 PM

Short answer: Yes. The AFM simply measures the amount of air going in. More air, more power. Think about some sort of CAI, because you've most likely just lost power from taking the top off the box and letting hot air in.

RM.

**wiso** · 15-02-2006, 11:51 PM

Originally Posted by mrxplode

im wondering will the ecu know the change in air flow thus increase performance????

probably not......

putting a pod filter on doesn't mean you get more air into the engine, the fact is an engine can only use soo much air, it is the vacum in the engine that sucks the air in when you open the throttle body, so it will only suck in as much as it needs, it is also this vacum that opens the flap door on the afm as it sucks the air in. plus all the intake piping can only let a certain amount of air in because of it restriced diameter.

so basically putting a pod on really won't do alot apart from sound cool and give a larger filtering surface for air from more than one angle rather than all coming through a small hole in one direction

**feral4mr2** · 15-02-2006, 11:52 PM

some ECU's require resetting (pull power for 5 mins or so) after changes such as a pod filter. not saying this applies to yours, though it may...

**mullett** · 16-02-2006, 12:26 AM

I''m not sure how accurate this is, because these are 'learning' ECUs, and they effectivley learn your driving styles and suchforth and adjust (within limitations) to suit. So if you change something, you're better off letting the ECU just sort itself out. If you reset it it has to start from step one all over again. I might well be wrong about this, I only messed around with it on an SR20DE for a while.

RM.

**mrxplode** · 16-02-2006, 03:18 AM

ok so my best option would be to get a piping made for the engine with a hole for the afm and a heat shieldand let the ecu do the rest...

ill get one off ebay

thanks guys

**Starfire** · 16-02-2006, 09:35 AM

The only thing you really need to look out for is in some cases if the pod is too close to the flow meter it can play up a little sometimes due to turbulence. If you have placed it where the standard filter goes then it should be fine.

AFIK toyota don't use learning ecus so there isnt really much to worry about there. If you do have one they adjust eventually anyway - they usually store 2 weeks worth of settings or so.

The trick with a pod is to get cool air in to it (box it up and duct it). They are illegal in most states if they arent boxed anyway as a backfire through one could theoretically cause a fire.

**4agte** · 16-02-2006, 10:53 AM

Originally Posted by wiso

so basically putting a pod on really won't do alot apart from sound cool and give a larger filtering surface for air from more than one angle rather than all coming through a small hole in one direction

well if the inlet of the airbox before the filter is restrictive the often are then it can make a big difference

**Nim** · 16-02-2006, 11:37 AM

As long as you're not sucking in too much hot air from the engine bay. Hot air = bad for performance.

The AFM detects how much air you're getting. If the pod does it's job, and does provide more air, then the AFM will know about it, and so will the ECU. Although, with an exposed pod in the engine bay I imagine you've just lost a few KW, not gained any. Especialy on a 7A-FE (which isn't designed to suck much air anyway).

mic* · 16-02-2006, 04:54 PM

MAF (mass air flow) sensors can accurately sense air flow in excess of what the given engine could swallow at max prm's and zero vacuum - which is the most air an NA motor can flow. They are over-engineered because they are pretty damn critical.

At WOT (wide open throttle) the major inlet restriction is the filter. If you reduce this restriction the engine should flow a bit more and the MAFs. will report this to the ECU -> more fuel -> more power.

A pod aims to reduce restriction by increased surface area, and to a degree better flowing shape.

I guess there could be merrit to what was said about putting one too close to MAF as turbulence could cause it to "flutter" which would result in poor tune.

As has been said make sure it doesnt suck hotter air than the box did. Very roughly every 2deg increase in intake temp cancels out every 1% flow increase. And pod filters heatsoak easily when the car is stationary...

**mrxplode** · 16-02-2006, 04:57 PM

hey someone told me to do this...

get piping to come to the front of the car with no pod or box and just put mesh at the joints in the pipes to block of stuff... he said thats the best way to get good a/f and cold air???

any thoughts on this...

**Squid** · 16-02-2006, 05:06 PM

Originally Posted by mrxplode

hey someone told me to do this...

get piping to come to the front of the car with no pod or box and just put mesh at the joints in the pipes to block of stuff... he said thats the best way to get good a/f and cold air???

any thoughts on this...

No filter = bad!! You can do it if you want to fuck your engine, but I think yo have got some really bad advice!

**Nim** · 16-02-2006, 05:16 PM

Yes, no filter = stuff gets into your engine. It doesn't have to be big stuff. Too much dust or small bits of grit aren't good for your engine.
Best thing to do is to run your pod to somewhere in your engine bay that gets lots of flow. Then get an extender pipe from your AFM to pod (I think 10cm should be more than enough, but if anyone out there wants to correct me, go ahead), put insulation around the back of the pod to block it off from the hot air off the engine bay. Make sure enough of the pod is free to flow air. Or you could run your pod to up in front of the radiator, but that depends on room, skill, and it might also get wet (which isn't good).

mic* · 16-02-2006, 05:21 PM

^^^ Agreed.

Wash out a filter after only a thousand k's and decide whether you would like the dust & shit to be grinding away your rings...

Cold air feed pipes (to a pod filter) are good, but are hard to do without looking ugly. And they really need to feed a box around the pod so that the pod must suck air from this cold location when there is not enough road speed to "ram" it up there. Otherwise the pod will heatsoak a lot worse.

If you can plumb a pipe to a sealed box, use the largest diameter you can fit so that the cold air pipe does not increase inlet restriction.