*How to* engine hatch scoop
#11
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#12
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Scoop looks great, you do need the holes. I have two scoops on my ride like the Raisen Bran commercial and they pack huge air at speed. The holes on the back release lots of air pressure. Kinda like a fart, pressure has to come out somewhere, right!
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#15
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I kinda figured the holes in the back would help out. That scoop is huge and will allow a ton of air into the engine compartment and there really isn't much ventege..(is that a word?) to release the air out. I just can't wait for the first time I stuff the boat and all that water makes it way into the scoop..Motor is going to love that
I'll post some more pics of me cutting out for the foam and vinyl to fit around the scoop tonight.
I'll post some more pics of me cutting out for the foam and vinyl to fit around the scoop tonight.
#17
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Just for informations sake, I measured the air pressure inside my engine bay at 100mph. Now consider theres a 900hp blower motor in there sucking up air as fast as it can and four double vents on the transom and it still registered 11psi above atmospheric pressure.
Thats with three 2" hole in the back of the same design scoop as the one pictured above.
It was enough prssure to force air between the hatch and rear seat back cushions on my Daytona and actually blow them loose from the velcro that holds them in place.
As for the scoop, did you use any filler in the gap between the scoop and the hatch? If not, I highly recommend you fill the gaps with an epoxy filler from inside the scoop to keep the water out and aid in bonding the scoop to the hatch. If you store the boat in freezing temps and any water gets collected in the gap, you know you'll be redoing the job next summer.
Thats with three 2" hole in the back of the same design scoop as the one pictured above.
It was enough prssure to force air between the hatch and rear seat back cushions on my Daytona and actually blow them loose from the velcro that holds them in place.
As for the scoop, did you use any filler in the gap between the scoop and the hatch? If not, I highly recommend you fill the gaps with an epoxy filler from inside the scoop to keep the water out and aid in bonding the scoop to the hatch. If you store the boat in freezing temps and any water gets collected in the gap, you know you'll be redoing the job next summer.
#18
Good advice. I made my own custom scoops, and when I glassed them on, I bedded the flanges down with 403 filler, then glassed both inside and out. I cut the hatch to fit the id of the scoop exactly, because I am going to have the big Eickert bonnets sticking into them.
I'm confused as to how you could get 11 psi in your engine compartment. The stagnation pressure of air (density=0.0025 lb-sec/ft^4) at 100 mph is only 0.2 psi. This, acting on a typical 8' x 8' hatch would be about 1840 lb of uplift on the hatch, which is obviously enough to cause a big problem. 11 psi would be 101,400 lb on your hatch. That would launch it somewhere into low earth orbit.
I'm confused as to how you could get 11 psi in your engine compartment. The stagnation pressure of air (density=0.0025 lb-sec/ft^4) at 100 mph is only 0.2 psi. This, acting on a typical 8' x 8' hatch would be about 1840 lb of uplift on the hatch, which is obviously enough to cause a big problem. 11 psi would be 101,400 lb on your hatch. That would launch it somewhere into low earth orbit.
#19
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I'm confused as to how you could get 11 psi in your engine compartment. The stagnation pressure of air (density=0.0025 lb-sec/ft^4) at 100 mph is only 0.2 psi. This, acting on a typical 8' x 8' hatch would be about 1840 lb of uplift on the hatch, which is obviously enough to cause a big problem. 11 psi would be 101,400 lb on your hatch. That would launch it somewhere into low earth orbit.