Extra power from Modified Genuine GM CAI

[ThongyVL]

Hey folks... not too sure if anyone has done this but I did this this afternoon, been running a VS Supercharged CAI and now have modified my CAI intake to almost 3 times the amount of air going into the engine. Here are the pictures of my modification. All you need is an angle grinder, file off the rough edges or use a sandpaper for smooth finishing. I felt that the gear changes are better and take off is MUCH better. If anyone can load a stock unmodified CAI so you can compare the difference in airflow. Also not too sure if doing this is legal of not...!!!

[Emackulation]

Hey folks... not too sure if anyone has done this but I did this this afternoon, been running a VS Supercharged CAI and now have modified my CAI intake to almost 3 times the amount of air going into the engine. Here are the pictures of my modification. All you need is an angle grinder, file off the rough edges or use a sandpaper for smooth finishing. I felt that the gear changes are better and take off is MUCH better. If anyone can load a stock unmodified CAI so you can compare the difference in airflow. Also not too sure if doing this is legal of not...!!!

Yeah, there are a few different modifications you can do to these, not all include hacking them. Of course its not illegal lol.

[kniever]

i also cut mine back as the opening was way too small from factory and i just wasnt satisfied. after cutting mine back the differance to me was ten fold and it felt alot more responsive so im happy with it now.

it wont let me post up the pics again so if ya wanna see them look at my ride thread

[89 vn]

I believe greenfoam did it aaaaages ago and posted pics, he used a heat gun and a block of wood wedge in the mouth, yeah no offence but I dont think opening your cai a bit more would give you much of a difference. on my VN i was running a front bar pipe and i added another pipe which sat a bit higher and i felt absolutely no difference. Just get a KN panel filter to make sure your getting the most out of it and remember tho the coolest air is at the lower/lowest point of your car

[VNV6VENGEANCE]

yeh i had thought of doing this but my idea was a bit different. If you look at the difference between the vs and vt sc cai the vt though being smaller has an angled inlet. (the top plastic is further back towards the engine than the bottom). Now this might just be to compensate for the bonnet closing issues a few people had with the originals but my bet is it increases the airflow. 89 vn has got it right no matter what you do to it you won't feel a major difference if any at all.

[Morton]

I've never been a HUGE fan of the OTR CAIs, but I can see what you've done there probably reduces response time a tiny little bit. I'm personally a fan of the box-to-front-bumper style CAI, where airflow isn't restricted by the bonnet rubbers, and is nice and cold

[kniever]

the gain wasnt major but it was noticeable to and just felt like it revved a little bit easier
and i took the rubber off that was right in front of the cai to let as much air as possible cos the size of the standard opening on the v8 ones is just rediculous, they really are a tiny opening and i cant see how it would do anything lol

[Bz Kn33z]

I have a VS S/C CAI and cut it back, not heaps only took it back 2cm where the lines on the CAI start and it opened up up more 1/3 more proberbly, and i also took the rubbers off the bonnet, i was going to try and make a shelid type of thing from the Letterbox grill up to the CAI so the air is going thro the letterbox grill and into it so more cold air gets in there, insted of being restricted by the VN bonnets, i was also thinking of running another pipe somewhere to the bumper as Morton has done and have both style CAIs.

[Morton]

[greenfoam]

The End, Morton wins ^

[PaRaDoX]

Looks like my home made CAI !

[ThongyVL]

Morton might win... But I see the ripples in the pipe causes restriction. Unless the bottom of the intake has a much greater volume than the ones in the pictures of the CAI cut out. Cold air is one thing, the other thing is how much volume of air flow you get into the engine is another.

[cracker]

its an n/a v6 not going to matter whole lot.

[greenfoam]

The airflow through a rippled pipe 110mm is so much more than a 65mm throttle can breath it wont matter to Morton, air temp is all that's important, you can't make much positive pressure through any pipe, just enough to take away the restriction of the filter is about all you can ask

[Morton]

Yeah, what greenfoam said It's 110mm, the largest I could get my greasy hands on, so it shouldn't cause restriction.

The reason I specifically chose ribbed pipe, (aside from the ease of installation), over creating my own smooth piped creation, was that the ribs in the pipe prevent water ascending, and catch 90% of the stones, flies, moths, rocks, leaves, and other debris that want to enter the airbox and clog up the filter.

When I take out the CAI every few months for a shakedown, you wouldn't believe how much crap falls out

I should really upload new pics of mine on the stato though. The silly looking cable tie is gone, and there's some light aluminium fly-screen mesh infront of it, to 1) hide it, and 2) prevent quite so many rocks, leaves and moths getting in there as did on my VP :P

[vnv8driver]

stock gm cai is crap tacular, hides behind the grille/bonnet and doesnt allow for a good amount of air to be forced into the collector, a setup like paradox's, mine or mortons forces alot more cool air to the filter, costs less and looks just about factory.

[89 vn]

Since ive ran front bar CAI inside my airbox ive found some stuff, small rocks, insects and some small leaves and a tiny ammount of sand. None of it made its way past the filter so it just stays in the box till you clean it out. Like Morton says the ribbed pipe is good but mine was even lower so it sucked more crap but it still was ok. Hate to see it w/o a filter tho..

[Morton]

hahaha, it's brilliant isn't it The amount of crap that manages to find its way up there. I'm actually amazed that small stones can find their way around the corners and up the pipe. I've had a few small ones, and I just can't picture them bouncing all the way up "by chance", because god knows there isn't enough suction in an induction system to drag them up

[Not_An_Abba_Fan]

A CAI doesn't actually gain power. All it does is increase responsiveness.

Oh, and the engine doesn't suck anything in. The low pressure caused by the piston moving down in it's stroke causes the higher surrounding atmospheric pressure to push air in.

[Chirpstr]

I cut mine to two small rings after seeing Abba fan with his one some time ago. The only thing, I tried to cut it on there and did a butcher job lol. Used soldering iron, hacksaw, allsorts lol. It's actually pretty thick stuff. I wasn't satisfied with how it was either I must say and still not although I did noticed a increase in air noise and suction after doing it. My gauge never goes over the quarter mark on temp gauge when crusieing...I think it would just hit the quarter mark when I first put the CAI on...so it does seem to breath better. Not sure about power increase though......
I might cut it like ThongyVL to neaten it up a bit so I won't have to hit myself every time I open the bonnet lol.

[Morton]

A CAI doesn't actually gain power. All it does is increase responsiveness.

I was under the impression that colder air is denser, contains more oxygen per cubic foot, and (in lay mans terms) makes the petrol boom better, which generates more power A CAI by definition has nothing to do with responsiveness, unless it's a ram-style CAI like on the LS2, which attempts to create positive pressure in the system. Even a bumper-ram system like mine has too many curves in it to generate significant positive pressure.

Oh, and the engine doesn't suck anything in. The low pressure caused by the piston moving down in it's stroke causes the higher surrounding atmospheric pressure to push air in.

And I believe that's what we call suction. Therefore, the engine sucks air in.

"Suction is the flow of a fluid into a partial vacuum, or region of low pressure." -wiki

[Not_An_Abba_Fan]

Unfortunately wiki isn't a scientific definition, but we are splitting hairs. Suction is the result of a vacuum, fluid dynamics and the way they move in atmosphere is the result if pressure differential. High pressure pushes fluid to low pressure, low pressure doesn't suck.

Yes, by definition a CAI should produce a colder more condensed charge, and by doing so it makes a more complete combustion resulting in better response, not more power. You are only putting as much air in as the engine can cope with. Forcing it in is an entirely different kettle of fish.

[Morton]

Unfortunately wiki isn't a scientific definition, but we are splitting hairs. Suction is the result of a vacuum, fluid dynamics and the way they move in atmosphere is the result if pressure differential. High pressure pushes fluid to low pressure, low pressure doesn't suck.

But splitting hairs is such fun ^___^

If creating low pressure in order to draw something in, is not suction, then what is? Say I were to use a straw to pick a crumb of chocolate off the table. I place the straw near the crumb, breathe in, and the crumb follows the flow of air through the straw, and into my mouth. Where I eat it. Could it not be said that I sucked it up? Or would we have to be technical and say that I created an area of low pressure in my lungs by moving my diaphragm and ribs outward, causing the high pressure around the crumb to move up the straw, dragging the crumb with it?

I think it would be acceptable to say I sucked it up ^__^

Yes, by definition a CAI should produce a colder more condensed charge, and by doing so it makes a more complete combustion resulting in better response, not more power. You are only putting as much air in as the engine can cope with. Forcing it in is an entirely different kettle of fish.

"more complete combustion" = more fuel being properly ignited = bigger boom = more power?

I thought it was a commonly accepted fact that cars will give a better dyno readout on cold days?

[immortality]

Unfortunately wiki isn't a scientific definition, but we are splitting hairs. Suction is the result of a vacuum, fluid dynamics and the way they move in atmosphere is the result if pressure differential. High pressure pushes fluid to low pressure, low pressure doesn't suck.

Yes, by definition a CAI should produce a colder more condensed charge, and by doing so it makes a more complete combustion resulting in better response, not more power. You are only putting as much air in as the engine can cope with. Forcing it in is an entirely different kettle of fish.

go get a large medical syringe, put your finger over the hole and pull the plunger down (just like a piston going down in the bore) it seems like suction to me.

CIA does improve power. cooler denser air contains more O2 so the PCM injects more fuel to maintain correct fuel to air ratios, that means more power. yes a engine will only suck as much air as it requires, however if oyu can increase the density and therefor the O2 content it's got to make more power

[Morton]

go get a large medical syringe, put your finger over the hole and pull the plunger down (just like a piston going down in the bore) it seems like suction to me.

CIA does improve power. cooler denser air contains more O2 so the PCM injects more fuel to maintain correct fuel to air ratios, that means more power. yes a engine will only suck as much air as it requires, however if oyu can increase the density and therefor the O2 content it's got to make more power

Thanks immortality ^__^ I was starting to think I as losing my marbles