Engine Starving for air?
07-24-2016, 07:34 PM
#11
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Mike you have the cowl like vents on each side where windshield ends correct. And then a single side vent on each side. Any way possible to get any other slim billet ones across the rear at same height as side ones or otherwise a little lower if need be. CP has a number of shapes and sizes as I'm sure you know.
Along with that is it possible to enlarge the forward cowl type ones even if you need to fabricate some custom vents. If I recall you don't have an over abundance of area there to enlarge but even a little could go a long way. I honestly believe your taking in no where near enough air and also not getting rid of what's coming in while obviously building lots of unwanted heat making tuning a nightmare as well.
Next time out pull all of your vents/cowls right out altogether. Ck out defender.com just to get an idea of some possibilities or ideas.
Along with that is it possible to enlarge the forward cowl type ones even if you need to fabricate some custom vents. If I recall you don't have an over abundance of area there to enlarge but even a little could go a long way. I honestly believe your taking in no where near enough air and also not getting rid of what's coming in while obviously building lots of unwanted heat making tuning a nightmare as well.
Next time out pull all of your vents/cowls right out altogether. Ck out defender.com just to get an idea of some possibilities or ideas.
Last edited by getrdunn; 07-24-2016 at 07:38 PM.
07-24-2016, 08:52 PM
#12
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http://www.defender.com/category.jsp...139&id=2290141
Not sure if you'd have any use for any of these however gives you some ideas. Get some dryer vent hose and duck tape also. Lol. All chit aside you need to get more air in and out of there.
Not sure if you'd have any use for any of these however gives you some ideas. Get some dryer vent hose and duck tape also. Lol. All chit aside you need to get more air in and out of there.
07-24-2016, 08:59 PM
#13
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The blowers don't have enough air flow to do anything at WOT, Idle and low cruise yes, WOT NO.
I had the same problem with the Scarab. I tried to find a solution but couldn't come up with anything that looked good.
The Daytona has the opposite problem. TOO much airflow - IF the hatch wasn't strapped down it would blow open. The previous owner did that a few times by the looks of the old hatch. I am going to seal the scoop to the flame arrestor.
I had the same problem with the Scarab. I tried to find a solution but couldn't come up with anything that looked good.
The Daytona has the opposite problem. TOO much airflow - IF the hatch wasn't strapped down it would blow open. The previous owner did that a few times by the looks of the old hatch. I am going to seal the scoop to the flame arrestor.
07-24-2016, 08:59 PM
#14
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Mike you have the cowl like vents on each side where windshield ends correct. And then a single side vent on each side. Any way possible to get any other slim billet ones across the rear at same height as side ones or otherwise a little lower if need be. CP has a number of shapes and sizes as I'm sure you know.
Along with that is it possible to enlarge the forward cowl type ones even if you need to fabricate some custom vents. If I recall you don't have an over abundance of area there to enlarge but even a little could go a long way. I honestly believe your taking in no where near enough air and also not getting rid of what's coming in while obviously building lots of unwanted heat making tuning a nightmare as well.
Next time out pull all of your vents/cowls right out altogether. Ck out defender.com just to get an idea of some possibilities or ideas.
Along with that is it possible to enlarge the forward cowl type ones even if you need to fabricate some custom vents. If I recall you don't have an over abundance of area there to enlarge but even a little could go a long way. I honestly believe your taking in no where near enough air and also not getting rid of what's coming in while obviously building lots of unwanted heat making tuning a nightmare as well.
Next time out pull all of your vents/cowls right out altogether. Ck out defender.com just to get an idea of some possibilities or ideas.
Here are the pictures of the vents I bought and I'm going to build these over the winter for the hatch. I think the rear vents will help both the heat escape and allow more air in.
Last edited by endeavour32; 07-24-2016 at 11:54 PM.
07-24-2016, 09:10 PM
#15
EZSTRIPER - Those fans exhaust the engine compartment they don't suck air in except by causing a negative pressure inside the engine compartment. Even if you installed them to pull air into the engine compartment all they would do is restrict the flow because the engines draw a LOT more air than what those fans will pull in. The open hole with the fan removed would allow more air flow. What they need is more or bigger holes to let air in.
You may not realize that I am an air flow specialist.
You may not realize that I am an air flow specialist.
07-24-2016, 09:38 PM
#17
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Steve-
What do you think about what I am considering to increase the flow of air. I'm not sure if the 4 vents in the back will do a lot, but I think the large cowl vent on the hatch will work well, plus the sun pad will still be usable.
What do you think about what I am considering to increase the flow of air. I'm not sure if the 4 vents in the back will do a lot, but I think the large cowl vent on the hatch will work well, plus the sun pad will still be usable.
07-24-2016, 10:57 PM
#18
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I don't remember what's behind your rear seat bottom and side but like other post mentioned that may be a possibility also. Take a look and see unless you already know however that's an area you could use something similar to link. Anything to get more air in there. I like your idea mentioned above and can only help. Might have to put a 12" sub grill in the middle of your back seat. Lol. Will be interesting to see what possibilities you may have along the sides of rear seat as well as enlarging the opening behind cowls.
Last edited by getrdunn; 07-24-2016 at 11:00 PM.
07-25-2016, 06:00 AM
#19
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Area of a 12" hole = 113.09734
Area of 2 x 6" holes = 56.54
07-25-2016, 06:36 AM
#20
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EZSTRIPER - Those fans exhaust the engine compartment they don't suck air in except by causing a negative pressure inside the engine compartment. Even if you installed them to pull air into the engine compartment all they would do is restrict the flow because the engines draw a LOT more air than what those fans will pull in. The open hole with the fan removed would allow more air flow. What they need is more or bigger holes to let air in.
You may not realize that I am an air flow specialist.
You may not realize that I am an air flow specialist.
Most 3" bilge blowers are 'rated' at 140cfm. Most 4" are rated at 240 cfm.
Each of your motors are demanding around 900cfm at WFO and top rpm. This is a very close accurate guess from many dyno's sheets measuring airflow on comparable motors. Therefore, your engines combined require 1800cfm ! That is a ton of air !
BTW: This subject is great and extremely impressed the OP tested this and reported it. Imagine how many people are running around with a performance boat and losing performance just like the OP ! And some, will perform more engine mods, drive mods, and etc, and still be choked down.
Many years ago, boat manufacturers started to become more aware of NVH (noise, vibration, harsheness) and started instituting methods to reduce thismore and more as time went on to make the boating experience even better. What's the easiest way ? Not just sounds insulation materials, but reducing the # and size of engine compartment openings. Ooops !
Remember, there is a reason the big old Apaches had big raised decks with holes or screens all over the place. Air !
