CAI Options.......just mulling this idea over

[markiii]

the one where teh intake pipe came out of my loft you mean? That was the prototype? In that case yes  :-) :-) :-)


the GB is a different matter  :-) :-) :-)

[Anonymous]

Oh - and I forgot to mention - the pipe doesn't exit into the wheel well - there is a fabric tube that goes over the top of the wheel arch, and re-enters the engine bay just behind the battery.

Right, that's where the first part of my "clothes-dryer CAI" goes i.e. between the stock inlet in front of and below the fuse box and the driver-side air inlet vent.

[Anonymous]

No one should expect any more than 3, perhaps 4HP, from any NA intake on this engine.  There are small gains to be had for a reasonable amount of money.  I've seen the dynos (independent testing).  There are pros and cons of different designs.

My intake is coming along pretty well.  The prototype had a problem and is in revision.  The guy who does the aluminim work (CeeDapp on SpyderChat) is making a replacement for the only stock part that I'm using. Meanwhile, I have something that works really well, but still uses the stock part (the short section of tubing where the MAF mounts).

The final design is basically an Erector Set type thing where you can quickly reconfigure the parts to optimize performance at different RPM ranges.  Originally there were only two possible configurations but I just realized there will be a third.  These are:

1. "Street" configuration (similar to AEM) -- for low to midrange RPMs.  The tube will be shorter than AEM's, the air filter located higher, and the resonator will be there, too.
2. "Racing" configuration (short, straight tube (Pelican Racing design) with the addition of a resonator which sits in a rubber Y -- for midrange to high RPMs with decent performance at lower RPMs.
3.  Pelican Racing design configuration (no rubber Y or resonator) -- you are all familiar with that.  You will not have to cut up your stock intake, though.

The rubber Y also makes the sound less shrill (absorbs higher frequencies), at least in the "Racing" configuration, which is all I have tested thus far.  I'll keep you posted.  You've been a lovely audience.   s:wink: :wink: s:wink:

[MRMike]

I've been watching your work on Spyderchat Beanie..fantastic initiative! Looking forward to seeing the final thing!  Hows's it sound at the moment?

[Anonymous]

Oh, thank you so much for the words of encouragement.  I've really explored quite a bit of options.  First it was going to be something that automatically switched intake tracts at two different crossover RPMs (one when increasing, the other when decreasing), but I found that to be just too darned complicated and expensive.

It sounds really good.  A sound clip would be possible, but you'd hear the TRD header and TM exhaust, so I'm not sure anyone would pick up the intake noise.  When you start up or shut down the engine you hear it because of the change in pressure, like an AEM except not as much of that (although the long tube, when connected, will probably sound very much like an AEM, given that the tube length is about the same and diameter is identical).  You also hear it under heavy accel.  It is quieter than the homemade Pelican Racing one I had on before.

Check out the Street/Racing Intake topic on SC.  I added a heat shield and am not sure if it helps any.  There is something different (maybe just the sound), but I can't even be sure if it is better this way.  It makes sense to me that the air would be a few degrees cooler, but airflow would have to be impeded somewhat.  I doubt the intake air is cooler by enough to make even 1/2 HP more, so it could very well be a wash (not make any difference at all).

It will be maybe 2-3 weeks before I can do more testing.  Corky is busy making more antiflex plates and battery boxes and I have to go away for a bit.

[MRMike]

Yeah I saw that thread Beanie..looking very promising indeed.  Are you planning on going commercial with these or planning on doing a write up as per Hong did? I'd be very interested either way!

Just a quick question, you say the MAF in the 'street' configuration will be placed on the long intake tract.  How close is it to the actual filter?  The reason I ask is that some people here have stated that with the Apexi they experience 'lag' between when the throttle is pressed and when the car accelerates. I was thinking that maybe this was because air took longer to reach the MAF from the filter than in the original OE configuration. Hence the time delay or lag.  Just wondered if your design suffered from this problem?

[Anonymous]

Are you planning on going commercial with these or planning on doing a write up as per Hong did?

I have been writing it up as I go and soliciting input (just like this).  I do not have any financial interest in anything I design for the car.  It is just a hobby.   The Lightweight Battery Box: I designed it, Corky built a prototype, (Corky then improved upon it... which he might also do with this for all I know), I tested and documented it, and he is selling them.  He also does this kind of thing as a hobby.  Nobody is going to make a whole lot of money selling aftermarket parts for this car, I don't think.  I have someone lined up to do independent testing when I am satisfied with it.  If it works well, I imagine Corky will start selling the kits.  Our arrangement is for me to pay for parts and he donates his labor, which I think is a good deal for everyone.  Another thing to consider is that it will be a kit and there is nothing to prevent anyone from modifying it, in fact I would encourage tinkering.  You can use whatever air filter you want, for example.

Just a quick question, you say the MAF in the 'street' configuration will be placed on the long intake tract.  How close is it to the actual filter?  The reason I ask is that some people here have stated that with the Apexi they experience 'lag' between when the throttle is pressed and when the car accelerates. I was thinking that maybe this was because air took longer to reach the MAF from the filter than in the original OE configuration. Hence the time delay or lag.  Just wondered if your design suffered from this problem?

There are two kinds of "lag".  In any tube, it will take longer for the pressure to change than in a shorter tube of the same diameter.  More on tube length in a minute.  The other kind of "lag" is the time delay between the time the airflow sensor detects (at the MAF) and when the signal makes it to the ECU and is processed... we need not worry about that.

The pressure change lag is a trade-off.  I had an AEM on my car before and I can't say that I noticed a lag before the car started to accelerate.  My long tube will give the whole intake tract (including the rubber piece and so forth after that) about the same length as the AEM... a little shorter.  You want the tube to be longer for normal driving, which is low- to mid-range RPMs, because of the resonant frequency.  Speaking of frequencies, the Heimholtz resonator will be present in both configurations (different location, though).

As far as the distance of the MAF from the filter goes, what is critical is for the MAF to be located a ways down a smooth straight tube so there is minimal turbulence, otherwise the ECU will not be able to accurately measure airflow, the A/F ratio will be wrong, and the car will not run well at all.  You may even get a CEL.  Supposedly the Pelican Racing intake, which has the MAF very close the the throttle body, does not cause a CEL.  That is probably because of two things.  One, it is a straight shot and the airflow is nice and smooth.  Two, it utilizes a stock intake part that has vanes inside (one inch before the MAF) to smooth the air.  I tried my intake with the stock MAF mount in that same location and a long tube hooked up and there was way too much turbulence... duh!... because of the bend in the tube right before that.  That's the reason for having a second MAF mounting point, just for the longer tube.  It will be in about the same location relative to throttle body and filter as on the AEM.

I think I got lucky on the "racing" configuration.  There is some theory behind it, of course, and I did the trial-and-error work, but hit upon something that works very well.  We'll just have to see how the "street" configuration works.

[MRMike]

Very interesting reading Beanie, ultimately it goes to show how good the standard set up actually is, and the amount of time and dedication it takes to make 'real' performance gains. Looking forward to hearing about the 'street' configuration sometime soon!

[Anonymous]

Update:

http://www.spyderchat.com/phpBB/viewtopic.php?t=11224&start=15

Too tired to install just yet.

[Anonymous]

Just a quick question, you say the MAF in the 'street' configuration will be placed on the long intake tract.  How close is it to the actual filter?  The reason I ask is that some people here have stated that with the Apexi they experience 'lag' between when the throttle is pressed and when the car accelerates. I was thinking that maybe this was because air took longer to reach the MAF from the filter than in the original OE configuration. Hence the time delay or lag.  Just wondered if your design suffered from this problem?

There are two kinds of "lag".  In any tube, it will take longer for the pressure to change than in a shorter tube of the same diameter.  More on tube length in a minute.  The other kind of "lag" is the time delay between the time the airflow sensor detects (at the MAF) and when the signal makes it to the ECU and is processed... we need not worry about that.

The pressure change lag is a trade-off.  I had an AEM on my car before and I can't say that I noticed a lag before the car started to accelerate.  My long tube will give the whole intake tract (including the rubber piece and so forth after that) about the same length as the AEM... a little shorter.  You want the tube to be longer for normal driving, which is low- to mid-range RPMs, because of the resonant frequency.  Speaking of frequencies, the Heimholtz resonator will be present in both configurations (different location, though).

As far as the distance of the MAF from the filter goes, what is critical is for the MAF to be located a ways down a smooth straight tube so there is minimal turbulence, otherwise the ECU will not be able to accurately measure airflow, the A/F ratio will be wrong, and the car will not run well at all.  You may even get a CEL.  Supposedly the Pelican Racing intake, which has the MAF very close the the throttle body, does not cause a CEL.  That is probably because of two things.  One, it is a straight shot and the airflow is nice and smooth.  Two, it utilizes a stock intake part that has vanes inside (one inch before the MAF) to smooth the air.  I tried my intake with the stock MAF mount in that same location and a long tube hooked up and there was way too much turbulence... duh!... because of the bend in the tube right before that.  That's the reason for having a second MAF mounting point, just for the longer tube.  It will be in about the same location relative to throttle body and filter as on the AEM.

I think I got lucky on the "racing" configuration.  There is some theory behind it, of course, and I did the trial-and-error work, but hit upon something that works very well.  We'll just have to see how the "street" configuration works.

A little contribution to discussion. I recently installed a PPE intake that use s a smaller piping than stock one and no vane. Running with stock ECU and pocketlogger together a wideband O2 sensor there isn't a cell light, but i have a little bogging and hesitation at low RPM . My pocketlogger says A/F ratio is too rich in closed loop and short table values are always negative.  In open-loop values are 12,5-12,7 at WOT ( slightly rich).
Also with Apexi Power FC, i have to take off a 5% of fuel when airflow levels are medium or low and rich A/F ratio at part throttle.

[Anonymous]

I would think that you would have just that... bogging and hesitation at low RPM due to no vanes and also worse performance than stock at low to midrange RPM due to short length.

I'm testing a short tube (replacement for stock part), same inside diameter as stock, but for now, w/out vanes.  Corky wants to know if vanes are really necessary (it is harder to make the part with vanes).  Yeah, they are going to be an improvement, absolutely.  They are there for a reason.  I may have some results by the end of the day... taking a break from the Florida heat.

By the way, I took your advice earlier and set all my airflow values to 94%... seems to make a very slight difference for the better (hard to tell).  I looked at O2 levels after disabling closed loop and values were closer to what I want.

---

EDIT: I think I said this earlier, but I cut up my AEM and used a short length of it (about 10") as a "short ram" intake and the car ran, but had the problems you mentioned.  The AEM is smaller inside than stock and has no vanes.

Everyone are going to have to wait, as will I, for test results.  SOMEBODY did something wrong.  I'll not reveal what it was or who that SOMEBODY is because SOMEBODY may be embarassed.  Also, SOMEBODY may think it is the other SOMEBODY's fault.    s:wink: :wink: s:wink:   It can be fixed and it is going to work like a champ.

[MRMike]

Hello again Beanie..I noticed on the Spyderchat thread you mentioned

"They say that you have to lower the intake temperature by about 10 degrees F in order to get 1 HP out of it"

Have you got this data, or was it just something you remembered?

Also really interesting to see effectively how much air the filter draws from the straight throught tube you've installed in the wing.  How long was it on there to get that dirty? Given that so much air seems to be drawn from there, have you not thought about a pipe with an enlarged end that would effectively cover the filter?

Really interesting read yet again Beanie

[Anonymous]

The filter was there for a few months.  I'm concentrating on getting more cool air to the filter because pipe length and diameter and filter are pretty much perfect.  Trying to eliminate or mitigate the increase in intake air temp that happens when sitting still or moving slow.  Installed large fan under decklid, but need a shroud.  Thinking about other options, like a powerful fan that would actually suck air from side vent and direct it at filter.  Hard to make something like that.

10degF cooler gives about 1HP is just a rule of thumb.  I think it is accurate.  Have you noticed the difference?  I certainly have in every small car I've owned.  10degC (about 18degF) is what I'd like to see... and what I think is very possible with the right kind of fan and duct.

[MRMike]

10degF cooler gives about 1HP is just a rule of thumb.  I think it is accurate.  Have you noticed the difference?  I certainly have in every small car I've owned.  10degC (about 18degF) is what I'd like to see... and what I think is very possible with the right kind of fan and duct.

Yes I certainly notice a difference. I posted before about performance loss in the heat, seemingly the GTECH showed a 10HP loss in a 13 degree difference in ambient temp.  I have no idea about the internal temps. Grant noticed similar losses.

My reason for asking for specifics was that I was thinking of ways of lowering the intake temp, and I wanted to see how much of a temp reduction I would have to get for it to have any effect on performance.  Seems the most efficient way by far, is by using NO2, something I'm loathed to do.

I was also then thinking, now this sounds crazy, and all common sense dictates it won't work, about lining the inlet pipe with Fridge freezer elements. But given the speed at which air must pass down this tube, there is no way I feel you could get significant temperature drop.  

Noticed you mentioned that with your intake in the 'race' setup the only problem you have found is standing heat dissipation.  You could perhaps fashion a small box with freezer elements that surrounds the filter in the race config, to prevent heat build up at slow speeds.  Then again given the results you found with the Heat shield, this may prove ineffective.

So ultimately that is the reason I enquired about the exact temp difference you would have to effect in order to gain performance, I'm very tempted to give the freezer elements a go in the inlet pipe I talked about before, if only to quell my own curiosity.

[Anonymous]

seemingly the GTECH showed a 10HP loss in a 13 degree difference in ambient temp.

That is hard to believe.  I'm not saying impossible, but wouldn't that be nice if it were true because it is fixable.

lining the inlet pipe with Fridge freezer elements. But given the speed at which air must pass down this tube, there is no way I feel you could get significant temperature drop.

No way is right.  Too much airflow to cool effectively.

You could perhaps fashion a small box...

I think the best thing to do as far as shielding goes is to do two things: (1.) wrap the intake pipe in lots of insulation and (2.) try to wall off the left 1/3rd of the engine bay.  There are a lot of hoses and things to the left of the engine, though.  I'll probably get around to making something that would work around the hoses, a vertical piece of aluminum.

I've posted some more info about fans on SpyderChat (topic starts with "Cooling fans").  To save duplication, I'll just post over there for a while.

[Anonymous]

I posted before about performance loss in the heat, seemingly the GTECH showed a 10HP loss in a 13 degree difference in ambient temp.  I have no idea about the internal temps. Grant noticed similar losses.

This thread will help:
 m http://www.spyderchat.com/phpBB/viewtop ... t=misnomer m

Note:  Engine bay temps might reach 120 - 150 degrees F.  Even if outside temp is 90 degrees, getting air from outside the engine bay (the drag racers' definition of CAI) can make a 60 degree difference.

So, it's critical to pick up intake air outside the engine bay.  This is why all those cone filters, which take air from within the engine bay are a bunch of junk!

[Anonymous]

With my racing intake, I see about 50C (122F) on my FC Commander when in stop-and-go traffic when the outside air temp is in the mid 90s.  Cruising on the highway, it drops down to around 38C (100F)... not much warmer than it is outside!  This is because I:

- removed plastic belly pan in the rear
- removed the "drip pan" thing under the slots in the rear
- have a hose routing cool air from the side vent to the filter (which evidently helps some)

This is WITHOUT any fans working.  There is a whole lot of airflow through the engine compartment at speed.  Ever look under your car?  Lots of spaces.

The problem with putting the filter in a cooler place is that the intake tract becomes longer, so the resonant frequency is lower and it is more restrictive than you want unless you are going for low-end torque.  These factors make a big difference.  It isn't all about temperature!

All I'm trying to do with the fans is make a good thing better by mitigating heat build up, to reduce the amount of time it takes to get the air temp back down where it should be.

I'm trying to have it all.  Two configurations, each one as good as I can possibly make it.  One for puttering around town, one for racing, with both of them better overall than stock.  What's not to like?  Prefer the longer intake with cooler air?  Fine with me.

[Anonymous]

The problem with putting the filter in a cooler place

Oh, I didn't mean to imply that the filter needs to be in a cooler place ... only that the filter's air souce needs to be from a cool place (i.e. outside the engine bay).

For example, if using one of those cone filters, it's important to have the filter covered in some container, which grabs air from ducting, leading to outside the engine bay.

Thus, the stock filter, which IS contained in a plastic box is pretty good - as long as one continues the ducting to outside the engine bay air.  Again, that "Misnomer: CAI vs HAI thread goes much further into this.

[Anonymous]

Completely enclosing the air filter and adding more tubing, so the tube is nearer to outside air, is pretty much the same thing as adding more tubing and putting the filter on the end.  That is what you are overlooking, apparently.

You should really TRY a different intake.  You seem to like experimenting.  I've tried a lot of different things, which is how I got to this point.

[Anonymous]

Completely enclosing the air filter and adding more tubing, so the tube is nearer to outside air, is pretty much the same thing as adding more tubing and putting the filter on the end.  

No ... the latter would leave the filter exposed to the outside elements, which is not what I'm saying at all.

[Anonymous]

I was talking about performance, not dirt.

You really should try a different intake.  I was a little skeptical about the AEM, but saw the dynos that were done at a shop in Atlanta.  The guy who showed me the results was Charlie Shatzen (spelling?), who makes the Team Moon exhausts.  He doesn't sell intakes.  He was telling me that the AEM and Injen are not much better than stock, how the stock intake already was a CAI.  There was a 2HP gain.  That small a difference is hard to measure, as there is some deviation from one run to the next.  They did multiple runs and the dyno compensates for ambient temps.  There was even a huge fan in front of the car (they did this with my Team Moon dynos, too).  I decided 2HP in the midrange was worth it and bought an AEM.  It really is a little better than stock, especially when you wall off the area the filter sits in.  I estimate +3HP for most temperatures.

[Anonymous]

Later on I decided I had nothing to lose and made a Pelican Racing intake.  There is a significant improvement at higher RPMs... I was very surprised.

All I'm trying to do (and so far, succeeding) is making each of these (shorter and longer) approaches to intake design better, fixing their weaknesses as best I can, plus making something that can be either one in about two minutes using just a screwdriver.  Bonus: having basic parts to let others play around with, possibly improving on what I did.

[Anonymous]

Check this out: http://www.gomiata.com/racbeatin.html

"Despite its higher intake temperatures, it remains the power king of the temperature-corrected dyno tests."

[Anonymous]

I won't be posting very often over here for a while.  Too many car boards, not enough time.  There is a topic on that new site (socalspyders.com) called "Modular Intake News" under the 1ZZ NA forum.  That's where I'll post the latest developments on that from here on.

Cheers to all my mr2roc.org/com friends here, especially those who have visited the new Southern California board.

Oh, one more topic over there may be of interest: "Karma Plus" in the Newbie Zone gives you a chance to get a free steering wheel badge (only one problem, though, it says "MIDSHIP RUNABOUT" instead of "MR2 ROADSTER") and possibly a Spider theme nose badge (no wording) that goes with the steering wheel badge.

[Anonymous]

I tested the prototype of the "racing" configuration today... success!  I received the two modified tubes from Corky/CeeDapp, but have only installed and tested the short one.  (I'm very busy.)

http://www.socalspyders.com/modules.php?name=Forums&file=viewtopic&t=242