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So I needed to get a smog check this year, every year I've had no issues but this year everyone says I need a legal intake and won't smog it. So I decided to make my own. If you have none of the supplies you could literally get everything for about $30, most likely you have most of it laying around, so it should only cost about $10. Tools/parts required are a measuring tape, pocket knife, trashcan/bucket, and hose. If you want the carb number you will need a metal plate or sheet metal scrap, even a dog tag would work, adhesive or rivet gun, and lettered metal stamps(you could just get a dog tag made at petsmart, engraved with the carb number for about $5.
So the first thing I did was measure where the box would go, remember to make it taller than needed, you could always shorten in but you can't make it bigger. You want it to seal up to the hood. I used a pocket knife for almost all the cutting in the project, you could use a dremel or razor if you don't have a good knife, my sv30 blade cuts everything like butter. began life as an $8 trashcan
Once you have it fitted where it needs to go, I began on the carb number plate I used a carb number from mishimoto it is on their site. Don't worry to much about gaps near the intake tube I cut a slit in rubber hose and put it around the hole to seal it. With carb number, you can attach it pretty much anywhere visible. This is finished with rubber hose for insulation. Passed smog and visual inspection no problem
My intake temps are now ranging from 70F-95F they only reach 95F when idling in LA traffic/ weather. Before this was installed my temps were 120F-150F. Originally i made this as a one day pass smog kinda thing. Now I'm going to keep it. I'm adding insulation tape on the outside of the box, nearest the engine, at the bottom. I don't want the silver tape visible. I also filled the hose with black rtv silicone caulk to keep it in place and make it more sturdy.
Not all smog techs are that stupid, I hope the next one fails you. Anytime we certify a car we put ourselves under penalty of perjury that we tested the vehicle correctly.
Not all smog techs are that stupid, I hope the next one fails you. Anytime we certify a car we put ourselves under penalty of perjury that we tested the vehicle correctly.
I think what this guy did was kinda useful. I get that perhaps you are a tech and you are against this. but for people in other states who don't need that carb metal thingy can gain from this. the stock intake is prob the best intake you can get for the Z and all these other intakes are just either for sound or aesthetics but if combined with proper insulation (like the stillen) this can be useful. my opinion is props to OP.
Edit* OP how did u record temps before and after? what instrument did u use
There's an intake air temperature reading you can read through a scanner. He's screwing with someones job, I don't like that. If he wants to get a smog license and pass it himself that's another story. Some of the dirtiest things I've seen have been on smog techs cars.
I don't think the tech was "that stupid" he checked the carb number and he looked the part up online and it matched. So no, I was not messing with anyone's job. He wouldn't get in trouble or lose his job, this does not look sloppy, it is mounted correctly, it has the carb number, when you check the number with the state it is valid, and when you look online the part looks nearly identical. The difference is mine is custom, cheap, and performs a lot better than it would without it. I have since insulated it more and compared tempts with a friend's jwt. Mine runs a lot cooler.
I use OBDLink it is a Bluetooth obd2 reader that connects to my tablet. I have access to around 250 gauges that I otherwise wouldn't, all wireless.
My car passed everything, I don't think it's right that the carb number is required in the first place, it has nothing to do with smog and everything to do with money. The company buys the carb number and in turn you have no choice but to purchase an overpriced product in order to register your vehicle. The whole carb number thing is a joke, it's extortion. To be street legal, smog checks should only measure the emissions and have a visual check for leaks. This helped me and I posted it hoping it could help someone else. Even if you're not in a smog state this is a helpful mod with self gratification.
My car did not come with the original airbox, the past 7 or 8 years there was never any issue with smog, this year it was. All my extra money has been going to cancer treatments, and this car being registered is crucial to me driving to those appointments. I don't feel like I or anyone else for that matter should pay $300 for something they can create for 1/10th of the price. As far as you hoping I fail next time is just cruel. Life is too short and people's hopes and wishes coming true is rare. I'm sure you can find something a lot better to hope for, I'll be happy to just be alive in 2 years when I need a smog again. If anyone would be so kind to share this link on their Facebook or anywhere else my family and myself would be very thankful.
I think what this guy did was kinda useful. I get that perhaps you are a tech and you are against this. but for people in other states who don't need that carb metal thingy can gain from this. the stock intake is prob the best intake you can get for the Z and all these other intakes are just either for sound or aesthetics but if combined with proper insulation (like the stillen) this can be useful. my opinion is props to OP.
Edit* OP how did u record temps before and after? what instrument did u use
Thank you, I tested the temps against a pop charger and this did a lot better. My friend went out and bought a Rubbermaid. I know it sounds funny using a trashcan, but it works. There is little to no heat soak, it's angled to accept the coolest air, and I honestly don't think it looks that bad. You wouldn't know it started life in the cleaning aisle of target.
Way to think outside the box with the trash can. Hopefully it will withstand the heat and hold up...
It's pretty dumb that a car would need a heat shield just to pass an inspection, and the fact that you have one on the car and the inspector actually took the time to look up the number is impressive..
My intake is carb legal and has a number on it without any heat shield would that mean it wouldn't pass in California?
I was going to fabricate my jwt heat shield or make something using a flower pot and fiberglass but damn looks like I might need to visit target for a Rubbermaid one... My temps are probably really high with my exhaust heat shields gone.
Way to think outside the box with the trash can. Hopefully it will withstand the heat and hold up...
It's pretty dumb that a car would need a heat shield just to pass an inspection, and the fact that you have one on the car and the inspector actually took the time to look up the number is impressive..
My intake is carb legal and has a number on it without any heat shield would that mean it wouldn't pass in California?
I was going to fabricate my jwt heat shield or make something using a flower pot and fiberglass but damn looks like I might need to visit target for a Rubbermaid one... My temps are probably really high with my exhaust heat shields gone.
what area are you in? I could check your before and after temps and help you make it, I wouldn't charge anything. You won't need the carb number since your intake has one already. I used the stock ztube and was just missing the box so I needed the Heatshield for smog. The Rubbermaid can withstand a bit over 400F so melting won't be an issue at all. I was even thinking about making it out of sheet metal and then use fiberglass body filter on the outside and paint for insulation, but the plastic works amazing so I'm going to stick with it.
edit* How do you like the kinetix upper manifold? I'm debating between that and a spacer. The kinetix does a great job of lowering temps as well, pairing it with a Rubbermaid would work wonders.
Thank you, I tested the temps against a pop charger and this did a lot better. My friend went out and bought a Rubbermaid. I know it sounds funny using a trashcan, but it works. There is little to no heat soak, it's angled to accept the coolest air, and I honestly don't think it looks that bad. You wouldn't know it started life in the cleaning aisle of target.
I did a lot of logging with my car and a popcharger. I was always 6 to 10 degree hotter then what was displayed as ambient while the vehicle was in motion.
I would think your design is great, but if you look at the JWT heatshield design, you would understand that most of the air comes in from the forward wheel well around , directly below the filter.
I did a lot of logging with my car and a popcharger. I was always 6 to 10 degree hotter then what was displayed as ambient while the vehicle was in motion.
I would think your design is great, but if you look at the JWT heatshield design, you would understand that most of the air comes in from the forward wheel well around , directly below the filter.
Yeah I know what you mean. Its hard to see it in the pictures but I cut the Rubbermaid can neat the fender wheel area and made a scoop. So the air coming from that area is forced into the air box. I kept the top so that it would direct all the air from the front bumper radiator support area directly to the filter as well.
Yeah California smog laws are ridiculous though, my intake tube and everything is stock I just don't have the box so it doesn't count. You either need a carb number on the box or the tube.
What size trash can was that? I can see it is a Sterilite brand, but wanted to get the exact one. This is a brilliant looking mod. I can now buy a cheap intake, and make my own heat shield for a grand total of $40 for all of it. Great.
And where do you get that kind of rubber hose for the edges? What specific name does that kind have?
Anyone on this for the size? Im thinking the 13.5 I think the size was, but want it exact before I start cutting. Sadly $4 makes a difference in my budget. Once my fiancé get out of Vet school maybe not, but before we are dating on left over change.
Thank you guys so much for going out on a huge limb and trying this stuff. I think the heat shield looks as professional as the one with the JWT, if not better. I had a JWT before I sold the car for the first time. Now I bought it back after my health issue was cured and now I am on a VERY limited budget and want to get that amazing sound back. My Test Pipes are hissing like crazy missing that extra air. LOLOL
Those trash cans are made from low temperature vacuum formed plastics usually polypropylene. The stock intake box is very well designed, I would get an '06 oem airbox (assuming you have a 03-05) with the velocity stack and a drop in filter, long before testing out trashcan intakes. You can also enlarge the intake tube very cheaply by buying silicone couplings and proper tubes on ebay to make your own custom intake.
That is a good point, but it doesn't get hot enough to deform I do not believe, but I have been SO wrong many, many times before. I do paint and body work and you really have to get a bumper hot for the paint to defect in it. I use a heat gun all the time to fix bumpers no one else would touch due to wanting to make money off painting, but I help people out on a limited income with liability insurance only and save the original paint and get the bends out mostly. Very rarely have a ruined the paint in the process, and I always have them sign a waiver that I am not liable if the paint is ruined. I don't think that would save me though if someone pushed it in court, but it is a worthy thing to me to save people who can't afford to repair their cars to a point of usability.
Overheating is a rarity, although I understand that the Duraflex stuff is a different chemical makeup than a cheap trash can. Id like to see the formula on that. I was a Chem major at UAB (but I love doing paint work, no use for my degree and I make more money than being in most labs all day long), so I'd like to see what kind of bonds the cheap trash cans have in them and what the temp is that will start to degrade at. You said regular 'ole Polypropylene is the usual plastic used?
While I do not do bumper repair or body work for a living, I am far from a rookie in working with plastics such as FRP and ABS. I have also made custom intakes from fiberglass which I know is way more heat resistant than vacuum formed trashcans. That said, if it is within your budget, or need it way below budget, I'd say the dollar store would be best since the ones at Target tend to be more expensive. Just take your stock intake box or take measurements to the store and compare it and figure out what you need.
05-06-2017, 12:55 PM
DIY CARB Legal Heatshield Intake
I have also made custom intakes from fiberglass which I know is way more heat resistant than vacuum formed trashcans. That said, if it is within your budget, or need it way below budget, I'd say the dollar store would be best since the ones at Target tend to be more expensive. Just take your stock intake box or take measurements to the store and compare it and figure out what you need. 
