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hey hey, read the topic from fastfreddygassit regarding his diy cai, it got me thinking...

has anyone thought of making a really short cia for an NB and putting a right angle bend the opposite way to stock, then afm and a simota type pod..? (pod would sit behind front right headlight...)

This setup would minimise any resistance thru the piping, being so short, and also keep the air intake away from the exhaust...

I am a draftsperson and i did some basic measurements on drew it up on Cad and it wiiiiiiill fit... im just unsure of how much air gets into that area and also whether there is a certain length you need from filter to intake manifold?

considering that the old carby engines had the filter directly connected to the carby, i dont think the distance matters... unless it is too noisey ...
so how much air gets into that area? how could i find out..?

this is just an idea so dont fire me down for mentioning it, but if any educated person out there could supplement my idea that would be great!!! criticism welcome too

You drew it up on CAD??? I just went to the local hardware and bought a piece of 90deg dunny pipe. Whacked the MAF and pod on the end and I had a super short CAI!

Didn't notice any real power improvement, maybe a touch in the top end. Revs nice, sounds awesome, but I used up alot more juice. Maybe due a little less lower end torque? I've got my CAI going across the front of the engine again now.

...dont you laugh at me!!! Haha im technical okay... (crock o crap)

how come it chews more fuel?how come you lose low end torque with less resistence? id think that the harder the engine needed to suck the more low end power lag youd get, and the more fuel you pump... surely the path of least resistence is greater...

hmmm... im starting to think that all this cai stuff is a waste of time...

Been discussed here recently and someone has an article about it.
You do lose bottom end torque if your intake piping is too short.

Bevan used more fuel because he liked the noise it made in the higher rev range, therefore his right foot gained some more lead, that is all

You will lose bothom end power. The length of the intake matters.

okay so scrap the short cai idea, does the fact that the air intake is so close to the exhaust really make much difference? or should i just get a no-drill mania cai?

what else can you do to get that extra bit of power without forking out $4000++ for a turbo or supercharger?

sorry if im repeating previous questions but the search never ever works for me, it comes up saying \"No topics or posts met your search criteria\"...

low and mid suffer a little and you gain a little at top end... feels likes theres a tad more throttle response too..

im happy with my cold side short cai which is pretty much exactly what bevan said in the first reply except im currently making a stainless elbow to replace the dunny pipe and i have some more dunny pipe acting as ducting or an air ram going from the front mouth upto the filter.

hey bevan that dyno day ages ago did you have a CAI on then? what power did you make? and what mods did you have?

also on anoter note.

if you want a cold side CAI you can retain a decent intake length and still stay on the cold side of the motor if you duct it smartly down into the front quarter kinda behind the head light and into the front bumper where you can make an air box with plenty of room and if you have fog light holes you can have the fillter pretty much out in open air.. i think the SP motorsport kit is like this or similar??

alternatively you can also follow the intercooler piping route and put a 90deg bend straight off the throttle body going down then pipe it to the same location as mentioned before.. might need a hole in the under body plastic tray but its only a plastic slpash guard and ive had no problems with this method (i used this route for my cold air ram that feeds my air box)

for me the best intake is short as possible and cold as possible as i believe this would be the best option for a car thats main use is on the track.. however ive been wrong before and am more than happy to be proved wrong so if someone has another idea let us know so i can give it a crack

I was looking into this fairly recently (like a month ago).

There are a few companies that manufacture them specifically in this location (Autoexe do one, as does RacingBeat), but it's not cheap. It definitely would look nicer than a DIY job, although if you just bought the plastic cover it'd look much neater.

The article about intake pipe length can be found here. It actually had a hand in helping me decide on not going with a super short CAI.

I would say the technical reasons for less power/torque low down, but increases high up, would be due to air turbulence. At low speeds, the air entering the intake would be fairly turbulent as it enters the throttle body relatively quickly and doesn't have a chance to \"smooth out\" as such. Because the air isn't \"smooth\", the air flow isn't efficient. Also, I would think that having a longer intake length would mean there is some air within the piping itself, which the throttle body would suck in from stop. If there's less piping at standstill, that means less air, which would translate into a less efficient burn at first. Meanwhile, at high speeds, the air is coming in so quick it's pushing all the air that's already in there harder, creating more pressure and thus has a much smoother air flow.

I'm not against the mania CAI, but I just thought there could be a more efficient way of getting air to the throttle body that didn't require that extra length of piping that runs along the side of the engine and the drilling. It seems like the air has that extra distance to travel and would require more force to move it through all the piping thus losing velocity as it finally made it to the throttle body.

Luckily enough, one of the guys I work with is mates with the guy that runs/owns SuziTech, and he was keen to get in to MX5's, so it was the perfect opportunity to get a CAI made up for me and for him to have a test vehicle to work off.

The end result was something very similar to the Racing Beat example, but with completely new piping, a cover piece (although not as nice as the ones autoexe/racingbeat have, but made of metal rather than plastic) and missing the bend of the racing beat one (ie it's just the filter sitting in line on the end of the piping, if that makes sense). Cost was $550. I don't know whether SuziTech will adjust their prices after having done mine. The guy who runs the place said it was that price because they did more testing/tuning/engineering/whatever than he first thought they would do to get it right, so that added a bit of extra cost to it. It might be cheaper now that they've done it once before and have a working model/design to build off.

As for power/torque, I haven't had a noticeable gain/loss low down, but there's definitely increased throttle response. It seems that when I get on the gas, it picks up a lot sooner. I've found that when I do step on it, the power in the engine is more readily available compared to before.

As for high end power, my NB8A with only the CAI modification pulled an extra 2kw more than a purely stock NB8A at the MX5 Mania dyno day this Saturday just past. The stock NB8A had about 25,000 less kilometres on it than my car as well. The extra 2kw isn't guaranteed to be down to the CAI, but I like to think it has something to do with it

The induction note is great when you're on throttle too. For my CAI, if you take it easy on the gas, the induction note sounds almost stock, but with a bit more body in the note (if that makes sense). But once you get on it and open it up, you really hear it go.

Sorry about the long post, but I hope the info helps

what you want is this in reverse for the cold side of the car



this gives you an idea of how it sits

That solution I think is quite costly. I remember looking at that one too when I was searching for info on it all. It also doesn't help if you have anything older than, and including, a NB8A.

It's a good idea though.

marcusus wrote:That solution I think is quite costly. I remember looking at that one too when I was searching for info on it all. It also doesn't help if you have anything older than, and including, a NB8A.

It's a good idea though.

hows the NB8A have problems?

irwin83r wrote:hows the NB8A have problems?

We don't have fog lights as stock. If you look at the pic, you'll see that it draws the air in from the fog light hole. You can of course cut a hole or buy an aftermarket bar with fog lights to convert it into an intake hole. Just that it's not as smooth or easy as having a 8B/C

BTW, SP Motorsport uses a scoop from the mouth of the car, NOT the fog light holes. The indentation on the box is for the back of the foglight to fit in nicely.

Here's your option

SP Motosport intake kit






AutoEXE




Custom CAI to standard airbox




CDA box