Injen CAI Airbox and Insulation DIY
#1
Moderator
Thread Starter
Injen CAI Airbox and Insulation DIY
In today’s engine design, the use of cooled turbo chargers are getting to be the norm. It cools down the air (via oil and/or coolant) and compresses it before introducing into the piston chamber thereby creating higher HP.
You truly need to scoop cold ambient air for the full potential of a CAI.
When driving at full speeds, cold air rushes through the engine bay providing cooling. Our CAI will suck almost fresh ambient air. It is when you are doing a lot of the daily stop and go, your CAI will be ingesting hotter air while sitting on idle.
When your car is on idle, basically sucking up the engine ambient air which is normally around 140~160 F. This is sometime evident when you punch your gas from a stop you may feel (or maybe not) this very slight hesitation of the engine, maybe caused by the hot air going into intake. Once you have taken off, fresh ambient air gets into the engine bay and all is well again.
What can we do?
An airbox shielding hot ambient engine air is an option. However you will need to create a direct path of ambient air since you have basically shielded your intake.
In the past, I have measured temperature readings on the engine bay (after running for quite a while) and saw these:
• Engine body: 165 F
• Engine ambient air: 150 F
• Injen body: 120 F
• Intake air filter: 100 F
Just imagine the heat absorbed by the air going into the engine through the short Aluminum CAI. The original intake system is plastic and therefore does not allow heat soaking from the engine bay.
DIY Plan to prevent-minimize heat soak
• Create an Airbox to shield the intake from engine. Apply a thermal barrier.
• Provide source of ambient cold air to the Airbox.
• Insulate the Injen body to prevent heat soak from the engine using a thermal barrier.
Airbox
In our SC for those of you who have the Injen CAI, there is a convenient corner that can be converted into an airbox. In fact there are pre-fabricated airbox-shield units on the market. I decided to create one for myself and see how effective it is. I used a 1 inch rigid foam and tie wrapped it.
Air path to the airbox
I actually opened up the headlamp rubber seal and installed a plastic scoop-diverted from the grille towards the airbox.
CAI insulation.
I have read a DIY on CAI insulation and I have requested for the author’s OK for me to post the link. This DIY details how to use a thermal barrier insulation found at your local HD (Reflectix, $10 for a 24” x 10’). In fact on this DIY, he has done some burning tests to make sure this barrier is safe for use in the engine bay, it passes. He also outlines tricks on how to wrap the elbows of the intake which is the only hard part of this DIY. With patience and practice, anybody can do it. I also used an aluminum tape made by Reflectix, $4.
I highly recommend fellow Injen CAI owners to perform this DIY.
Pictures to follow.
You truly need to scoop cold ambient air for the full potential of a CAI.
When driving at full speeds, cold air rushes through the engine bay providing cooling. Our CAI will suck almost fresh ambient air. It is when you are doing a lot of the daily stop and go, your CAI will be ingesting hotter air while sitting on idle.
When your car is on idle, basically sucking up the engine ambient air which is normally around 140~160 F. This is sometime evident when you punch your gas from a stop you may feel (or maybe not) this very slight hesitation of the engine, maybe caused by the hot air going into intake. Once you have taken off, fresh ambient air gets into the engine bay and all is well again.
What can we do?
An airbox shielding hot ambient engine air is an option. However you will need to create a direct path of ambient air since you have basically shielded your intake.
In the past, I have measured temperature readings on the engine bay (after running for quite a while) and saw these:
• Engine body: 165 F
• Engine ambient air: 150 F
• Injen body: 120 F
• Intake air filter: 100 F
Just imagine the heat absorbed by the air going into the engine through the short Aluminum CAI. The original intake system is plastic and therefore does not allow heat soaking from the engine bay.
DIY Plan to prevent-minimize heat soak
• Create an Airbox to shield the intake from engine. Apply a thermal barrier.
• Provide source of ambient cold air to the Airbox.
• Insulate the Injen body to prevent heat soak from the engine using a thermal barrier.
Airbox
In our SC for those of you who have the Injen CAI, there is a convenient corner that can be converted into an airbox. In fact there are pre-fabricated airbox-shield units on the market. I decided to create one for myself and see how effective it is. I used a 1 inch rigid foam and tie wrapped it.
Air path to the airbox
I actually opened up the headlamp rubber seal and installed a plastic scoop-diverted from the grille towards the airbox.
CAI insulation.
I have read a DIY on CAI insulation and I have requested for the author’s OK for me to post the link. This DIY details how to use a thermal barrier insulation found at your local HD (Reflectix, $10 for a 24” x 10’). In fact on this DIY, he has done some burning tests to make sure this barrier is safe for use in the engine bay, it passes. He also outlines tricks on how to wrap the elbows of the intake which is the only hard part of this DIY. With patience and practice, anybody can do it. I also used an aluminum tape made by Reflectix, $4.
I highly recommend fellow Injen CAI owners to perform this DIY.
Pictures to follow.
#2
Lexus Test Driver
iTrader: (1)
somebody is waking up. the injen is sucking in hot air. guys are putting in there cars injen that suck in hot air because they like the sound the hell with the sound. the one thing you don't do is suck in hot air. I never said nothing because this was cool thing. I hope all you guys are all hearing this. if you never been into racing you will never know. its called cold air not hot.
Last edited by bacardi11; 07-11-13 at 11:17 AM.
#3
Moderator
Thread Starter
There is hope. Good sound and COLD air. Like cold beer.
Ever since I had the Injen put in, I reach out and touch the intake filter and I say...hhmmm hot to touch.
After I installed the box and insulation, there is a huge delta temperature drop from before. I tested it last night.
Today I will run errands and will bring my temp gun and get some data. We need data to support the claim.
Ever since I had the Injen put in, I reach out and touch the intake filter and I say...hhmmm hot to touch.
After I installed the box and insulation, there is a huge delta temperature drop from before. I tested it last night.
Today I will run errands and will bring my temp gun and get some data. We need data to support the claim.
#4
Moderator
Thread Starter
Here's a shot of the installed Injen...
#5
Moderator
Thread Starter
#7
Moderator
Thread Starter
I will measure temps today and publish, makes a huge difference. Not pretty looking but functionally works well.
Trending Topics
#8
Moderator
Thread Starter
#9
Lexus Test Driver
iTrader: (1)
mandy
the best mod. would be is have a hole cut in side in the stock air-box run a hose below the car with a scoop setup to get the cold air to the stock air-box that would be the set-up. insulate all hose to the stock air-box, insulate inside of the stock air-box and insulate to the engine inlet. use with K&N filter i'm not into the sound so this is my way
the best mod. would be is have a hole cut in side in the stock air-box run a hose below the car with a scoop setup to get the cold air to the stock air-box that would be the set-up. insulate all hose to the stock air-box, insulate inside of the stock air-box and insulate to the engine inlet. use with K&N filter i'm not into the sound so this is my way
Last edited by bacardi11; 07-12-13 at 01:41 PM.
#10
Lexus Test Driver
iTrader: (8)
mandy
the best mod. would be is have a hole cut in side in the stock air-box run a hose below the car with a scoop setup to get the cold air to the stock air-box that would be the set-up. insulate all hose to the stock air-box, insulate inside of the stock air-box and insulate to the engine inlet. use with K&N filter i'm not into the sound so this is my way
the best mod. would be is have a hole cut in side in the stock air-box run a hose below the car with a scoop setup to get the cold air to the stock air-box that would be the set-up. insulate all hose to the stock air-box, insulate inside of the stock air-box and insulate to the engine inlet. use with K&N filter i'm not into the sound so this is my way
#12
Moderator
Thread Starter
#13
Moderator
Thread Starter
#15
Moderator
Thread Starter
You mean the fender?