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ok,I have been wondering why alot of people have the scoops on the carb turned backwards(facing the back of the boat).You would think with it turned backwards it is defeating the purpose or am I missing something?
 

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ok,I have been wondering why alot of people have the scoops on the carb turned backwards(facing the back of the boat).You would think with it turned backwards it is defeating the purpose or am I missing something?
The chevrolet engineers may have been onto something with the cowl hood.:)sphss I bet it makes little difference either way.
 

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As long as you can keep the water out.:)hand
 

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If you don't have a spark arrester on the carb, you can't run it facing the seating area per coast guard . If the motor backfires the people in the back seat get real short hair quick.Also spray over the bow can go straight into the carb.
 

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Water doesn't "compress" (air fuel mixture does) if your engine inadvertantly takes a "big gulp" of H20 eg a wave over the bow or?? its very likley a catastrophy of mangled rods , pistons and maybe block iron will occur I ran it backward on my cruiser to reduce the noise but personally I run them forward for the most part Tom
 

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The chevrolet engineers may have been onto something with the cowl hood.:)sphss I bet it makes little difference either way.
The chevrolet engineers determined in the area where the hood ends and the windshield began there was a high pressure area so cowel induction was born. In truth you are correct as other than getting relatively cool dense air compared to hot under hood air there was little benefit in the location itself outside of marketing.
 

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The chevrolet engineers determined in the area where the hood ends and the windshield began there was a high pressure area so cowel induction was born. In truth you are correct as other than getting relatively cool dense air compared to hot under hood air there was little benefit in the location itself outside of marketing.
It was the NASCAR people that 1st used cowl induction. Since the rules dictated that they had to keep everything under the stock hood the air was ducted to the air filter from the cowl grill below the windshield. This idea goes back to 1962 or 63.
 

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...eliminates water ingestion and long hair incidents, there is a LOW pressure area created, which feeds a high-volume, of "clean" air to the carb, reduces noise, and I think it looks/integrates better on the engine hatch...not sure on the spark arrestor comment tho...
 

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There are 2 theories on this and they both have been covered! It started with the circle boats that get water splashed at them all the time and grew to just keeping the solid (water) out of the motor. An ingestion of water can turn a rod into a shoehorn in a heart-beat. A lady,girl or long hair guy sitting in the back seat can get a major headache just as fast. The air moving around the scoop plays funny games and can actually hamper air flow into the carb. Look at velocity stacks. if you have ever ran one or do, make a good pass and shut down asap then run you're finger around the bell of the stack. That moisture you feel is the air being sucked back out of the carb. If you don't believe me---Taste it. M
 

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i used to have a 4 inch cowl induction hood one a camaro, of mine. If there were any pollen or rain water beads on the hood, it would oll up the hood and SHOOT into the cowl induction . i can see where there would be just as much power as a scoop facing forward, plus you can reep the benefits of everything else everyone has already mentioned.
 

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i used to have a 4 inch cowl induction hood one a camaro, of mine. If there were any pollen or rain water beads on the hood, it would oll up the hood and SHOOT into the cowl induction . i can see where there would be just as much power as a scoop facing forward, plus you can reep the benefits of everything else everyone has already mentioned.
Only thing is that with the cowl induction hood, I had a 3" on a 02 Z28, you have to have something behind the scoop for the air pressure to build up on. In a boat, there's nothing behind the backwards scoop, just open air.
 

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Out of curiosity we ran my buddies boat, who had a backwords scoop, with GPS and ran three passes at 62 mph. Then turned it around facing forward and ran three passes at 57 and 58 mph. As far as we could tell, all things were equal. Not sure what it means but I now run mine facing back (for the water thing as well).
 

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Bigtorq....How BIG a scoop did you have?

On the cars of the sixties and early seventies, most of the scoops didn't do much.....the one on the Rambler scrambler maybe showed some benefit....I've always wondered hoe efficient the Formula Firebird "Boundry layer scoops were....but the best system was where the just attached the snorkle to the radiator support, so the high pressure created in front of the radiator was fed into the carb.
 

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Bigtorq....How BIG a scoop did you have?

On the cars of the sixties and early seventies, most of the scoops didn't do much.....the one on the Rambler scrambler maybe showed some benefit....I've always wondered hoe efficient the Formula Firebird "Boundry layer scoops were....but the best system was where the just attached the snorkle to the radiator support, so the high pressure created in front of the radiator was fed into the carb.

Scoop also has a flame arrestor inside. In order to turn it to the back I'll have to install a spacer to keep it above the dist.
scoop.jpg
 

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Bigtorq....How BIG a scoop did you have?

On the cars of the sixties and early seventies, most of the scoops didn't do much.....the one on the Rambler scrambler maybe showed some benefit....I've always wondered hoe efficient the Formula Firebird "Boundry layer scoops were....but the best system was where the just attached the snorkle to the radiator support, so the high pressure created in front of the radiator was fed into the carb.
I think that on most of the cars from that era with whatever ram air setup they had, the scoops probably did more to screw up the af and flow thru the carb then they did to add power. A steady supply of hot air under the hood, then the thing opens at speed introducing cool turbulent air.......if I was drag racing my Mustang with the shaker it would probably be more consistent with a big open air cleaner under the hood than it would be with the shaker and that small air cleaner element that it uses. I think CVX is right, the setups with the ducts to the front of the car would have been the best.
 
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