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ttoyoda · 05-29-2008, 06:23 PM

Hi trikkonceptz

The only ignorant questions are the ones that are not asked.

If you can get away with only using one speaker port it would be ideal.
If you need a bigger area than that, I would suggest a single bigger hole.. I suspect that the hole counts as a reduction of your frontal area as well

For the bigger hole, If you can cut the speaker port into 4 segments along its axis then you could use those segments for the corners of a rectangular port, Or cut it into 2 segments and make an obround port and have an easy job radiusing the straight sides of the rectangle or obround.

About the duct, I want to be clear that the duct should expand evenly and continuously from the small port area to the larger radiator area. I do not suggest you use spiral wrap ductwork hose or dryer hose and just point it at the radiator (well, unless you try it and it is good enough

). You will get the best efficiency out of your radiator if you can get uniform air velocity across the entire frontal face of the radiator. Fast airflow on a small area of the radiator and slower flow on the rest will give you less efficiency. If you were to make a duct out of sheet cardboard and duct tape to start you can find out what port area you need. The long nose will let you make a long duct, which will help get the air spread out.

Also, I assume the exhaust manifold and/or cat are on the front of the engine just behind the radiator? These items reach a significant temperature, and thus "radiate" heat at the back side of the radiator (the radiator paradoxically gets rid of most of its heat thru forced convection ). If you can install one or two or 3 layers of sheetmetal, spaced apart from each other (so air can get in between) and from the exhaust manifold/cat 1/2 inch or so, you can block the radiative heat transfer from getting to the radiator. Ideally, no part of the radiator face can "see" any part of the exhaust manifold or cat converter. Pretend the surfaces of the exhaust manifold and cat are giving off light, you want the radiator to stay in the dark, but of course you need to let air get out the back of the radiator.

05-29-2008, 06:23 PM	#59 (permalink)
ttoyoda Master EcoModder Join Date: May 2008 Location: boston ma Posts: 381 Thanks: 0 Thanked 5 Times in 5 Posts	Hi trikkonceptz The only ignorant questions are the ones that are not asked. If you can get away with only using one speaker port it would be ideal. If you need a bigger area than that, I would suggest a single bigger hole.. I suspect that the hole counts as a reduction of your frontal area as well For the bigger hole, If you can cut the speaker port into 4 segments along its axis then you could use those segments for the corners of a rectangular port, Or cut it into 2 segments and make an obround port and have an easy job radiusing the straight sides of the rectangle or obround. About the duct, I want to be clear that the duct should expand evenly and continuously from the small port area to the larger radiator area. I do not suggest you use spiral wrap ductwork hose or dryer hose and just point it at the radiator (well, unless you try it and it is good enough ). You will get the best efficiency out of your radiator if you can get uniform air velocity across the entire frontal face of the radiator. Fast airflow on a small area of the radiator and slower flow on the rest will give you less efficiency. If you were to make a duct out of sheet cardboard and duct tape to start you can find out what port area you need. The long nose will let you make a long duct, which will help get the air spread out. Also, I assume the exhaust manifold and/or cat are on the front of the engine just behind the radiator? These items reach a significant temperature, and thus "radiate" heat at the back side of the radiator (the radiator paradoxically gets rid of most of its heat thru forced convection ). If you can install one or two or 3 layers of sheetmetal, spaced apart from each other (so air can get in between) and from the exhaust manifold/cat 1/2 inch or so, you can block the radiative heat transfer from getting to the radiator. Ideally, no part of the radiator face can "see" any part of the exhaust manifold or cat converter. Pretend the surfaces of the exhaust manifold and cat are giving off light, you want the radiator to stay in the dark, but of course you need to let air get out the back of the radiator.