CAI & Snake Oil whats the diffrence

[XRchic]

We did our own with a GT snorkel behind the headlight. We have a pod and an additional intake above the radiator. Seems to work quite well, but that is when the Unichip is tuned for it, and in conjunction with other mods (ie headers, exhaust).

Re engine bay heat - it got hot enough under our bonnet to fry the Unichip which was located there....

Anyway, I think you can do CAI cheap yourself, quite easily, with the right bits. I think it cost us all up $50 and took half an hour or so.

Pics are in this thread... last post of page 3.

http://www.fordforums.com.au/showthr...8&page=3&pp=25

[4.9 EF Futura]

Well i voted for the second option because that seems like a reasonable response when looking at the phrase literally.

I'm sure that drawing in fresh air from outside the vehicle is worth something - otherwise im sure ford would have simply had an air filter hanging off a MAF hanging off the throttle body.

Am i convinced that modifying the standard intake is good for the kind of gains that are being thrown around? Probably not. That's not to accuse anyone of being deceitful - that's genuine, healthy scepticism. Particularly when considering the price for some of these modifications. I mean, for that kind of money I could replace the intake manifold on the 5.0L and hopefully see a bit more than 5kw-10kw.

Surely restriction plays just a big a role as temperature?

Anyone have manifold vac readings before/after intake mods?

[brenx]

jonbays : CAI definately works. Even on old carbed cars. It shows up in the mph section of a slip. Which should also hopefully improve the ET. It's easy to see a 5rwkw difference. These variables will change as you dyno intake temp, humidity and airtemp. Through-out a day here in Vic it changes quite considerably.

[gozza]

i can say with certainty its helped my car

the pod helped with the throttle response
i modded the box to fit the pod as a heat sheild and a short pipe down into the wheel arch

its works better off the line cos off the trapped heat...even if its getting a little extra cold air...its better than none

[BENT_8]

When we say Cold Air Induction we are simply referring to bringning cold air from outside the engine bay, and to a lot of people who want CAI they are sold larger snorkels.
If i took the headlight out of an EF- EL we'll say for example and cut the front out of my air box and made a plastic tube to go from the headlight surround to the air box will this make my engine gain revs faster?
maybe slightly. Other than being illeagal it does nothing more than allow max air to sit in the air box. It still has to be drawn through that small opening at the end of the induction tube which is plainly smaller in diameter than the throttle body.
Common sense says that if you remove the ristrictor and allow more air to get from the air box to the throttle body, the throttle body will allow more air to enter the engine at full throttle therefore creating quicker engine response.
Only then should air temp become a performance gain.
Perhaps CAI should be sold as Improved Induction and include snorkel, pod or panel filter and the induction pipe as a complete performance kit and not just a filter and a snorkel for minor gains

[Des]

Here's a couple of facts.
Cooler air is denser air.
Denser air means more oxygen per litre (of air).
Denser air can carry a better 'fuel-air-charge'.
Better 'fuel-air-charge' will give better efficiency.

Denser air will generally fatten the torque curve, (giving a back-handed increase in kw), for a specific rpm. As someone said earlier, an engine is basically an "air-pump". Now relating this to the laws of pnuematics/hydraulics. A system is restricted (in flow rates) by the smallest (internal) diameter in said system (very basically). To put this into other words, if you have 100mm pipe in between two 75mm holes, you're still restricted in how much and how fast you can flow by the two 75mm holes. Now you can get around this by increasing the force and speed of the flow or by increasing the size of the holes to match the connecting pipe. Smoothing out a system will also give gains as unwanted 'swirls and eddys' in the system will rob your flow rate (as will too many turns as this will heat the 'flow' through increased friction).

Now, either of the two mods in isolation, will give you gains. But the combination of both will give you the maximum gain. Especially if you increase the engines ability 'breath out' as well as to 'breath in'.

This is a pretty basic outline, but the rules are still the same:
1. Clean and cool inlet material
2. Smooth and cool inlet path, matched to flow of motor
3. Smooth outlet with efficient heat dissapation, matched to flow of motor

So you want as much cool, clean air as you you can stuff into the bugger!

[BENT_8]

I sort of looked at it this way, if you took a phase 3, which has the greatest form of CAI i ever seen on a factory performance vehicle, and took the large flowing 4 barrel and manifold off it and ran a small 2 barrel instead with the scoop what would happen to the power?
surely the restricted size of induction would take away from all that air being drawn in through the scoop.
If you slotted a 302 with 2 barrel under the bonnet of the phase three and hooked it up to the scoop will it go as fast as a 351 with the extra cold air or will it just suck in its full displacement of air and go marginally better than with a standard air cleaner.
Perhaps if you then put a 4 barrel onto the 302,( overkill i know) opening up the area of induction surely it would create more horsepower.
Yes a 4 barrel will also flow more fuel but a I6 ECU directs fuel by air flow not air temp so it too would flow more fuel with increased air flow

[SSBUB]

over the radiator cold air induction on a gen 3 works quite well (not SS inductions, they are very restrictive). But alas its a holden so im not sure if that answers anything

[Des]

Originally Posted by BENT_8

I sort of looked at it this way, if you took a phase 3, which has the greatest form of CAI i ever seen on a factory performance vehicle, and took the large flowing 4 barrel and manifold off it and ran a small 2 barrel instead with the scoop what would happen to the power?
surely the restricted size of induction would take away from all that air being drawn in through the scoop.
If you slotted a 302 with 2 barrel under the bonnet of the phase three and hooked it up to the scoop will it go as fast as a 351 with the extra cold air or will it just suck in its full displacement of air and go marginally better than with a standard air cleaner.
Perhaps if you then put a 4 barrel onto the 302,( overkill i know) opening up the area of induction surely it would create more horsepower.
Yes a 4 barrel will also flow more fuel but a I6 ECU directs fuel by air flow not air temp so it too would flow more fuel with increased air flow

Here's an easier example. How do Nascar restrict power and speeds? Restrictor plates. These plates basically sit over the carb and effectively (literally) reduce the cfm. Also, simply giving an engine more fuel and air mixture will not give you extra power, you have to give it the right amount/ratio.
Lets put it this way, getting more fuel/air mixture into your engine (obviously no overkill here) will produce more power than simply sucking in cooler air (prior to changes). But, feeding your engine cooler air will allow it to (especially ecu engines) run more efficiently as it sits now.
All performance relies on quality as much as quantity (air included).

[bwhinnen]

Des, well done, the first to pick up on the cooler air is more dense.

This is the key, also last time I looked the MAF actually will pick up a) the temp of the air charge flowing past it and b) the amount of air (amongst other things) these in most ECU's will be parameters used to deliver the desired fuel charge and ignition timing.

Not being an expert (in any shape or form) on the Ford ECU I cannot say how it works exactly, but given a normal ECU there will be a distinct advantage to cooler air charges as it can deliver more fuel and because the intake charge is cooler and thus more stable apply more advanced ignition timing (through the use of the knock sensors closed loop function aka a rudimentary self learning ECU).

On subject though, if the CAI is well designed and does indeed bring in ambient temperature air to the air filter and thus engine it will give a gain in a modern car with any form of knock compensation and MAF. On an older car with carb and standard old style vac advance dizzy more needs to be done to make the most of it otherwise it may just run a little leaner.

Sorry to jump in as a newb.

Cheers
Brett

[gozza]

Originally Posted by bwhinnen

Des, well done, the first to pick up on the cooler air is more dense.


Cheers
Brett

i knew as im sure 90% of people do

[BENT_8]

Of coarse air temp will vary combustion performance and effect engine performance, but the original question asked was do CAI's make a difference to the people who walk in off the street and buy a snorkel and filter and believe they have a power upgrade because its a general term given to a couple of overpriced add ons.
Why do people change the MAF on windsor 5.0's?
Proberbly has something to do with being the narrowest point on the intake thus restricting flow. All im trying to say is that there is a lack of fabricate yourself parts left on a modern car so if having a mendral bent and welded pipe designed by yourself and installed yourself can have an excellent effect when used in conjunction with other mods, why would you pay big dollars for an off the shelf kit.

[bwhinnen]

Originally Posted by BENT_8

Of coarse air temp will vary combustion performance and effect engine performance, but the original question asked was do CAI's make a difference to the people who walk in off the street and buy a snorkel and filter and believe they have a power upgrade because its a general term given to a couple of overpriced add ons.
Why do people change the MAF on windsor 5.0's?
Proberbly has something to do with being the narrowest point on the intake thus restricting flow. All im trying to say is that there is a lack of fabricate yourself parts left on a modern car so if having a mendral bent and welded pipe designed by yourself and installed yourself can have an excellent effect when used in conjunction with other mods, why would you pay big dollars for an off the shelf kit.

Agree 100%, if you can do it yourself for a fraction of the cost and get the same (or better in some cases) results why wouldn't you.

As to the MAF, people change that as the current one is a restriction. It all comes back to how much it can flow, remembering that usually the MAF is only 0 - 5V and once you reach a certain air flow the MAF is outputting near enough to 5V so even if the size (diameter) of housing is big enough to flow more air the element can't output a voltage big enough for it... (regardless of temp :P ) And I know I'm stating the obvious ...

As to the cooler air being dense comment, sorry call me Mr. Obvious, even though I would assume most people realise it I thought I'd state it anyway :

[1TUFFUTE]

Great read an nice poll Jonbays.

So what were saying is that cai does seem to work ok but only if done well and by well we mean do it yourself instead of paying 500-700$ for pretty bits.
Is that a fair sum up...

[5speedeb]

Originally Posted by dev5 ute

Great read an nice poll Jonbays.

So what were saying is that cai does seem to work ok but only if done well and by well we mean do it yourself instead of paying 500-700$ for pretty bits.
Is that a fair sum up...

good question

[XTC 190]

I reckon thats a fair assumption, you could make any thing home look just as pretty with a little time and patience, theres a lot of areas piping or ducts could be run in the frontof a falcon so look and decide which way is better,as in my case I have ot quite good gains from home made and I have still got to access all available cold air or forced air which ever way you want to look at it.

[Des]

Originally Posted by Falcon73

I reckon thats a fair assumption, you could make any thing home look just as pretty with a little time and patience, theres a lot of areas piping or ducts could be run in the frontof a falcon so look and decide which way is better,as in my case I have ot quite good gains from home made and I have still got to access all available cold air or forced air which ever way you want to look at it.

The problem for me was the confines of the BA engine bay. Trying to find someone with access to 3.5 inch aluminium (stainless won't give a short enough bend), was the main issue. I could of had something made up otherwise for around $180 for the XR. Instead I had to buy a Power Pipe for $225. My main concern in getting as much good quality air into the Boss as possible, so intake restriction and intake temp are of concern.

[Chris]

People who post up gains on a particular intake bear watching, unless they can tell the entire story in detail. It has 4 chapters i'll list below.

It is all about removing the restrictions in the order in which they are most apparent.

I haven't posted any dyno sheets redarding the air intake we designed and use on our BOSS motors, because the results do differ depending on mods.

Posting dyno sheets is OK, but not everyone has the same mods, same air, same temp, etc, so the results dont always qualify for real world. This is why we have a 1/4 mile.

Story is like this - Engines are air pumps. Air goes in, gets squashed, gets blown up, gets pushed out.

CAI's help get the good air in, valvetrain events help squash it, ignition system bangs it, a good exhaust gets it out.

If a car has potential for 50rwkw increase, you will get generally the most from your exhaust and intake, but to properly recognise the potential of an air intake, you need a good exhaust.

I always recommend either first, but my head will always side with exhaust, then CAI.

if you are dollar concious and may, but maybe also may not later fit an exhaust, you will not recieve all the benefits that a good cold air intake has to offer.

A CAI is not the be-all and end all, so threads regarding such need to do proper testing on a variety of vehicles, including with a factory system. More often than not, if you have a factory system, an ultra high flowing intake may not give you the gain that Joe Blow recieved, as he has more restriction out of his car by having a zorst.

Peace out

[Stav]

What have I missed!!! Jon Bays the best i6 cold air intake is J&U cold air intake.(Jonbays and Useless)

You saw what happened at the fpv intune dyno day.My 5 dollar stormwater pipe only showed a 1 kw restriction after I ripped it off on my second dyno run..

The J&U cold air intake retails for 770 dollars . Real results...real people.

Ultimately I think its a crock of crap unless you have a big cam.

[Quadcams]

Originally Posted by useless

What have I missed!!! Jon Bays the best i6 cold air intake is J&U cold air intake.(Jonbays and Useless)

You saw what happened at the fpv intune dyno day.My 5 dollar stormwater pipe only showed a 1 kw restriction after I ripped it off on my second dyno run..

The J&U cold air intake retails for 770 dollars . Real results...real people.

Ultimately I think its a crock of crap unless you have a big cam.

What you say it lost 1kw when you pulled it off mmmm..... pay for what you get.

Believe it or not Stav big cam, small cam, 4cly to v8 they work I have had them on all.

But as Chris said you have to have the right set up top get gains.

[4.9 EF Futura]

Originally Posted by bwhinnen

This is the key, also last time I looked the MAF actually will pick up a) the temp of the air charge flowing past it and b) the amount of air (amongst other things) these in most ECU's will be parameters used to deliver the desired fuel charge and ignition timing.

Whilst not relevant to the discussion at hand, its probably worth noting that the MAF sensor doesnt measure the ambient temp of the air entering the engine. It heats a small sample of the air, and measures how much current is required to heat the air to the desired temperature - by measuring the input current to the heating element, it can determine the mass of the air entering the engine. There is a seperate sensor for air intake temp....

How do Nascar restrict power and speeds? Restrictor plates. These plates basically sit over the carb and effectively (literally) reduce the cfm.

Goes between the carb and the manifold dunnit? Lol, not that it matters....

[CAMS290]

Originally Posted by useless

What have I missed!!! Jon Bays the best i6 cold air intake is J&U cold air intake.(Jonbays and Useless)

You saw what happened at the fpv intune dyno day.My 5 dollar stormwater pipe only showed a 1 kw restriction after I ripped it off on my second dyno run..

The J&U cold air intake retails for 770 dollars . Real results...real people.

Ultimately I think its a crock of crap unless you have a big cam.

As long as your happy !!



:

[Stav]

Originally Posted by Lowride260

What you say it lost 1kw when you pulled it off mmmm..... pay for what you get.

Believe it or not Stav big cam, small cam, 4cly to v8 they work I have had them on all.

But as Chris said you have to have the right set up top get gains.

I believe you mate. Chris is right .It must be set up right to get gains.But there are limits. An engine can only pump a certain amount of air.Overporting,over throttle bodying,over intaking will reduce air speed and power. The fuel spray must be kept in the air stream not puddle. On the other side a too small ports,throttle bodies and intakes will have a higher air speed ,good low to midrange power but choke power up top.
Without a doubt in my mind using this information can we truly predict power increases from a bigger air intake.
Another point is that power will increase from afreer flowing intake because of less engine lossess on the induction stroke of the engine but only when the intake complements the airflow speed required to get max power.A restrictive intake will sap power from the induction stroke.

At the end of the day this is the irrefutable scientific basis for improvements.

[buickman]

The thing I found was that with a T/series snorkel & 3" mandrel intake on a VCT AU mtr & stock AC delco A/filter on the same dyno gave a 2.2rwkw gain over a stock AU intake & K&N filter.
I didn't notice that much in driving the car performance wise but when I fitted a large in air box podfilter the car would rev much better & seemed to redline faster as well so I would expect with the pod filter, T/F snorkel & 3 " mandrel intake my gains would have been over 5rwkw by the feeling of how the car performed. Pity I sold the car before I could have dyno'd it with the set up.
But extractors & exhaust gives the best performance gain for the dollars spent I found on my AU.

[bwhinnen]

Originally Posted by 4.9 EF Futura

Whilst not relevant to the discussion at hand, its probably worth noting that the MAF sensor doesnt measure the ambient temp of the air entering the engine. It heats a small sample of the air, and measures how much current is required to heat the air to the desired temperature - by measuring the input current to the heating element, it can determine the mass of the air entering the engine. There is a seperate sensor for air intake temp....



Goes between the carb and the manifold dunnit? Lol, not that it matters....

I suppose it depends on the style of MAF, but those I've dealt with will heat the wire to a set level above ambient, thus needing to know the ambient temp in order to keep the wire heated to the set amount above it can then calculate the mass of air past it, rather than a set temp as discussed by you. Some ECU's can use this temp as well, but you are right most / some will utilise a seperate AIT sensor to determine the temp of the intake charge at a determined point in the inlet tract for the ECU itself.

I will step back in my box now though, as what I was thinking really doesn't make sense when I think about it properly (sorry I tune speed density over MAF in preference). Given that the MAF (hot wire / film) will heat to a constant above ambient, it really doesn't matter what the temp of the air is, because the measurement is always a constant above that ambient temp anyway, unless the way the hot wire / film reacts to the ambient air is different for different temperatures giving a different amount of current required to keep it at that constant temperature...

Not being argumentative, I enjoy discussions about technical things...

Sorry to move off topic.

Brett

[XR_Strider_GuY]

I too have played the backyard modifying of intakes. However I am aware that there is no magic big gain horsepower to be had.

My aim was to merely open the intake up abit to get abit more cold air in the process as the standard intake of the AU looked rather small compared to the EF setup. The result I believe is abit better throttle response and maybe a kw or so in power if that.My other aim was to make an intake system that looks factory.

Heres my setup and incidently it costed me under $100 for everything.

[FPV329]

Originally Posted by SSBUB

over the radiator cold air induction on a gen 3 works quite well (not SS inductions, they are very restrictive). But alas its a holden so im not sure if that answers anything

And of course you flow tested an SSI unit to come up with that statement?

I know people that have.

SSI stuff seems to work mighty fine on mine and my sons SS and looks pretty good too.

[WILDTRAKPX2]

Originally Posted by FPV329

And of course you flow tested an SSI unit to come up with that statement?

I know people that have.

SSI stuff seems to work mighty fine on mine and my sons SS and looks pretty good too.

I'll second that. It's very trendy to knock SSI...

[EB Pete]

well this is what i came up with.





now if that does not give me any gains in hp/Nm i will be very surprised.

[Aaron_EF8]

Why didn't you cut a hole in the inner guard and run a pipe from the bumper? Seems like a neater option.

I personally don't see how that will produce a noticeable amount of power, but in saying that, it won't lose power either.