Completed CAI project. (2nd Gen V6)

[Custom88]

it sounds the same as the stock airbox during normal acceleration. You don't hear it until you get on it atleast 1/2 throttle, or over 3,000 RPM.

[oldsauroraman1]

Are we talking a need for ear plugs?

[Custom88]

oh, definately not. It's not that loud. It is definately noticable compared to stock though. The stock airbox was so quiet because of all the bends the air had to make and because it was divided into different chambers. THe different chambers muffler the sound quite a bit. Now there's nothing around the filter at all. The Classic Aurora on the other hand only had the single chamber then it got air directly from that chamber. The intake on the classic is noticably louder than the 2nd gen's intake because of this reason. Mine will be a little more quiet once I build the heat shield.

[Aurora40]

stevensolds said:

Bob, would you consider doing this mod? I think it might make your track times better by a tenth or two. It was a rocket compared to a classic as i remember, but improvements can always be made. I noticed nothing from a K&N panel drop-in. Dissapointed needless to say, for spending $60.

No, but I don't want to take away from Dan's thread. I think with a box around it, a cone might help a bit, though.

[20inchaurora]

hm might be something i'll have to look in to

[Custom88]

Well, the cold air intake is now complete! I spent right around 4 hours fabricating a plexiglass box to put around the airbox and PCM. The plexiglass was kind of a pain to work with. It kept cracking on me. I finally ended up melting/cutting it with a soldering iron then snapping it to make my 'cuts.' The airbox was then wrapped in reflectix which is a heat insulator. The airbox is totally sealed from the engine bay and it draws in air from directly behind the headlight just like stock, plus the small 2x1 inch hole on the side of the fender which also goes directly behind the fender. Total cost was somewhere around $140 or so..





The airbox goes down so far to totally protect the PCM from engine bay heat/water and to not let you see the wire harness coming from the PCM




It looks really great in person and overall I'm pleased with how it turned out, and the nice difference in performance!

[Aurora40]

That looks really nice Dan! I'm sure it was a pain to get it fitting so well, though. Good work!

[95mushroom]

Congrats! Looks great! Was fun working with that plexiglass stuff huh? What stuff did you end up using (lexan, that weird stuff Lowe's has..)?

I have to get pics and a vid for mine up.

Question, though, what did you do about the engine rock? I was going to fasten mine down, but noticed the assembly rocks a bit during various throttle applications. And I using the stock elbow which was designed to flex. I imagine your alum. elbow doesn't at all.

[Custom88]

I'm glad you asked that. I took flex into the design of this intake. The bottom of the air 'box' sits against the fenderwell. It is not attached to the radiator area at all though. I also made slack between the airbox and the sides, and front. I tested it with the brakes applied and throttle applied to torque the engine. The box will move/shift fine without affecting anything. I also made a small gap between the pipe and throttle body so that the coupler can flex if need be. It should be good to go. I also wrapped reflectix on the intake pipe near the throttle body to block heat from the exhaust manifold. This Reflectix doesn't melt or burn does it? I hope not. Don't need an under hood fire from it being so close to the intake manifold.


PS. I did go with the LEXAN from lowes. It was cheap and it's fairly resiliant. It's just a pain to "snap" it when you're cutting your pieces out. It likes to crack instead of snap along the line you make.

[scottydl]

Awesome! That really took some ingenuity and fabrication skills on your part, man. Other than sound, how would you describe and rate the performance increases vs. the time/cost that you put into the project?

[Aurora40]

custom88 said:

This Reflectix doesn't melt or burn does it? I hope not. Don't need an under hood fire from it being so close to the intake manifold.

Well, it's aluminum foil with bubblewrap sandwiched in it. The bubblewrap could melt/burn if it was hot enough. How hot do you think it will get? I wouldn't think the intake manifold would be a problem, but I wouldn't put it over the exhaust crossover if you think it might be close. Better safe than sorry with something like that.

[Custom88]

I think it was worth it for the performance increases. One thing that drove me absolutely nuts about the 3.5 V6 was how gutless it felt at mid throttle and in the mid RPM's. This addressed that issue nicely. The throttle response has increased by quite a bit. It doesn't seem a lot faster at WOT, nor at light throttle, but midrange power is definately noticable like mentioned above. One beautiful thing about reflectix is that it covers up the flaws in your fabrication. The lid did not line up perfectly with the sides because it's not a rectangle, nor a square. The reflectix and tin tape cover that up nicely. I did make the top removable by removign two screws on the top of teh lid, then sliding it forward and straight off. This way the entire box doesn't have to be removed to service the air filter. The tape does have to come off though. That's not big deal though.

Bob, the reflectix is about 1.5-2" away from the manifold. I guess it should be alright. The stock intake was just as close and was made of rubber so if that's ok without melting this stuff shoudl be too I suppose. It's important in this spot because it's where the IAT sensor is located. I might move it to somewhere closer to the air filter later on though.

[stevensolds]

Very well done....i could never have spent 4 hard hours like that. lol. Looks great tho

[JimW]

Success on your part Dan, congrats on a great effort. I'm sure we'll refer to this thread many times as members want to get a bit more from the 3.5 V6.

I wish I had the time to do something to mine (err I do not mean you don't have important things to do with your time btw )

Kudos to you!

[covert420]

Very Nice! I am going to do the same to a V8 I am getting soon. Letting that V8 DOHC breath better (and colder) should open it up in a big way. It's going to be a custom job just like yours and the one ZZP makes for the 3800 engines.



If this can bring a 3.8L V6 SOHC a solid 5-10HP, then it should bring the 4.0L V8 DOHC engine an easy 10-15HP.

(p.s. I am also considering a FWI)

[oldsauroraman1]

Very nice Dan. Any improvement in MPG?

[Custom88]

no idea on gas mileage for two reasons. First is that it's getting colder out so I let it warm up for 1-2 minutes before hitting the road. Secondly, the performance increase has made me enjoy the new found power a little more if you know what I mean. I accelerate a little quicker than I used to, but usually not more than 1/4 throttle. Those two factors combined have netted me a loss of 2 MPG average over the course of this being installed. (I think a little over a week now?) I think the cold weather is the biggest factor though. I won't know actual improvements in economy until spring/summer time unfortunately. I can't see it being worse than stock though in anyway. This intake was a huge breather for the engine. (pun intended) the stock setup was not good for flow/velocity.

[BuccaneersFan]

Very nice job on the intake.

custom88 said:

no idea on gas mileage for two reasons. First is that it's getting colder out so I let it warm up for 1-2 minutes before hitting the road.

Do you mean because your letting the car warm up for a couple minutes and it's just sitting there idling, the mpg reading isn't accurate? Because since the weather has been getting cooler down here my mileage has gone from 19.3 to 21.1mpg.

[stevensolds]

I usually idle it for 3 or 4 minutes when chilly out before i even put it in gear..should be less start-up wear over time than someone just starting it up and gunning the engine (what the hick behind us does..and he even revvs the motor in -10 degree weather

[Custom88]

buccaneersfan said:

Very nice job on the intake.

custom88 said:

no idea on gas mileage for two reasons. First is that it's getting colder out so I let it warm up for 1-2 minutes before hitting the road.

Do you mean because your letting the car warm up for a couple minutes and it's just sitting there idling, the mpg reading isn't accurate? Because since the weather has been getting cooler down here my mileage has gone from 19.3 to 21.1mpg.

I let the car idle in park for several minutes before I back it out of the garage and get underway. I'd like to keep the engine in good shape for many years to come. My gas mileage is now down to 25.7 MPG average. (two months ago I was sitting at 26.8 MPG average.

[jonaurora02]

Is there any effects with the ECU. It looks like it's in the air box to help keep it cool and if you take it out of there it may over-heat correct???

Jon

[Custom88]

what's the ECU?

[austinator]

custom88 said:

what's the ECU?

Engine Control Unit

[Marc]

It's also known as the PCM.....Powertrain Control Module.

[Custom88]

ahh. I wasn't thinking.. It's not too often on the boards that it's referred to as ECU. hah.

[jonaurora02]

So back to my question.... is there any effects???

Jon

[Custom88]

there are not any effects on the computer. it is 100% water tight. The Bonneville crowd has done this type of modification for years, and none have experienced a PCM failure to date.

[deepthinker22]

Post dyno Results if you can or 1/4 mile ASAP. Interested to see it.

[austinator]

Considering this was a year ago and he no longer has the car...I doubt that will be happening.

[ajxtcman]

custom88 said:

Inside the 2nd Gen airbox


airbox removed:


PCM In place:


I agree supa, there's a LOT of improvement to be made on both generations.

Not all of the air filter boxes are the same.
I will post some more info on them. They have noise control air boxes