gaza1970
New Member
- Joined
- Sep 21, 2005
- Messages
- 15
- Reaction score
- 4
- Points
- 0
- Age
- 53
- Location
- Adelaide, SA
- Members Ride
- 99' VT V6 Series 2 Berlina
Hi, With rising fuel costs and the discussion about air boxes and snorkles, I have thought about what you guys have been saying and I have experimented with getting more cool air the box too.
A week ago, I first started with removing the bottom section of the box and rubberbanding the air filter to the top of the box, just to see if it made a difference. As I didn't want to cut holes in my box unless it demonstrated results.
Well, I noticed the difference with smoother running, more power and better fuel economy - when the engine is sucking cool air... after the engine bay warmed up, performance dropped, but still improved from the factory setup. (Try it yourself! Remove the bottom of the air box (3 hex head screws) and hold the air filter securely using 3 large rubber bands, let the 'head' rest in the engine bay and take it for a drive.
Anyway, today after studying under the bonnet where to put a duct and with what, I found two right angle 90mm stormwater angle bends and some length of stormwater pipe. Maybe if I ducted some positive pressure air up from the bottom of the car, it might work?
(If you really look at the snorkle that is factory fitted by Holden, when the bonnet closes, it's suprising that it sucks any air at all!)
I took the bottom box off and traced around the pipe. Using a soldering iron I cut the circle in the bottom of the air box and reinstalled - (I thought using an iron might be easier than a drill, hacksaw blade and file.) Here's a pic.
After a bit of measuring and rooting around, I made up what looks like a periscope which picks up cool air from the bottom of the engine bay and takes it to the side of the box. I have put length measurements of the pipe in pencil on the pipe.(300mm & 70mm) Here's a pic. Note: I have cut off half the flange on the bottom 90 angle which makes it fit better under the car.
FYI, I have a V6 Ecotec Berlina, 150K kms and there seemed to be enough room in between the radiator and engine components to mount the 90mm pipe.
I initially used some cable ties to mount the pipe but have since used some small right angle brackets that I made up out of a piece of flat steel bent in a vice. The brackets hold the pipe in the airbox. I did keep the two cable ties used at the bottom of the duct
I have also cut a small section of the bottom cowling so it doesnt obstruct the air flowing into the angle bend. Here's another pic.
Here is a view looking down, the pipe is clear of all fans and hoses, I have used some silicone to seal the pipe where it enters the box.
I reassembled the unit by putting the filter back in and the top back. Disconnected the battery for an hour (to reset the computer)
Took it for a test spin and it works like a dream, providing positive pressure in the tube. The tube is steep enough not to attract water or rain up into the air box. The only thing that maybe a concern is - it was warm under the bonnet after my test drive and the storm water pipe was warm, so I dont know if it will distort the pipe (I shouldn't think so).
To finish off I just need to use a bit of black paint. It's quite discrete looking from the front of the car. All up cost me about $10. I will let you know if I have any problems.
After thought - If I had a 'rectangular down pipe -> 90mm adaptor,' on hand. It looks like this, but not attached to a house!
I could have added this to the bottom angle bend. This would provide a nice rectangular pick up and I would imagine fit nicely in the cowling slot. Probibly adds an extra 5 bucks to the cost of the project. I might go to the hardware tomorrow and see what I can do.
A week ago, I first started with removing the bottom section of the box and rubberbanding the air filter to the top of the box, just to see if it made a difference. As I didn't want to cut holes in my box unless it demonstrated results.
Well, I noticed the difference with smoother running, more power and better fuel economy - when the engine is sucking cool air... after the engine bay warmed up, performance dropped, but still improved from the factory setup. (Try it yourself! Remove the bottom of the air box (3 hex head screws) and hold the air filter securely using 3 large rubber bands, let the 'head' rest in the engine bay and take it for a drive.
Anyway, today after studying under the bonnet where to put a duct and with what, I found two right angle 90mm stormwater angle bends and some length of stormwater pipe. Maybe if I ducted some positive pressure air up from the bottom of the car, it might work?
(If you really look at the snorkle that is factory fitted by Holden, when the bonnet closes, it's suprising that it sucks any air at all!)
I took the bottom box off and traced around the pipe. Using a soldering iron I cut the circle in the bottom of the air box and reinstalled - (I thought using an iron might be easier than a drill, hacksaw blade and file.) Here's a pic.
After a bit of measuring and rooting around, I made up what looks like a periscope which picks up cool air from the bottom of the engine bay and takes it to the side of the box. I have put length measurements of the pipe in pencil on the pipe.(300mm & 70mm) Here's a pic. Note: I have cut off half the flange on the bottom 90 angle which makes it fit better under the car.
FYI, I have a V6 Ecotec Berlina, 150K kms and there seemed to be enough room in between the radiator and engine components to mount the 90mm pipe.
I initially used some cable ties to mount the pipe but have since used some small right angle brackets that I made up out of a piece of flat steel bent in a vice. The brackets hold the pipe in the airbox. I did keep the two cable ties used at the bottom of the duct
I have also cut a small section of the bottom cowling so it doesnt obstruct the air flowing into the angle bend. Here's another pic.
Here is a view looking down, the pipe is clear of all fans and hoses, I have used some silicone to seal the pipe where it enters the box.
I reassembled the unit by putting the filter back in and the top back. Disconnected the battery for an hour (to reset the computer)
Took it for a test spin and it works like a dream, providing positive pressure in the tube. The tube is steep enough not to attract water or rain up into the air box. The only thing that maybe a concern is - it was warm under the bonnet after my test drive and the storm water pipe was warm, so I dont know if it will distort the pipe (I shouldn't think so).
To finish off I just need to use a bit of black paint. It's quite discrete looking from the front of the car. All up cost me about $10. I will let you know if I have any problems.
After thought - If I had a 'rectangular down pipe -> 90mm adaptor,' on hand. It looks like this, but not attached to a house!
I could have added this to the bottom angle bend. This would provide a nice rectangular pick up and I would imagine fit nicely in the cowling slot. Probibly adds an extra 5 bucks to the cost of the project. I might go to the hardware tomorrow and see what I can do.
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