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Re: Sealed Hood to Air Pan
[Re: Leigh]
#917165
01/31/11 12:18 PM
01/31/11 12:18 PM
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Joined: Sep 2003
Posts: 2,008
Sweet Home Alabama
MRMOPAR622
top fuel
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top fuel
Joined: Sep 2003
Posts: 2,008
Sweet Home Alabama
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When you seal the scoop if the car does not pick up,the scoop is the problem. Most of the time being the scoop opening is not large enough,also some scoops just will not work on some cars. You may also need to go up on your jet size a few steps. The extra air can cause it to lean out.This will most likely be your problem than the scoop opening being to small.
Last edited by MRMOPAR570; 01/31/11 12:25 PM.
"To Be The Man'You Have Got To Beat The Man"
"T/D and Pro-Bracket Racer"
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Re: Sealed Hood to Air Pan
[Re: MRMOPAR622]
#917166
01/31/11 01:20 PM
01/31/11 01:20 PM
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Joined: Oct 2004
Posts: 8,166
Left Coast
BobR
master
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master
Joined: Oct 2004
Posts: 8,166
Left Coast
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Quote:
When you seal the scoop if the car does not pick up,the scoop is the problem. Most of the time being the scoop opening is not large enough,also some scoops just will not work on some cars. You may also need to go up on your jet size a few steps. The extra air can cause it to lean out.This will most likely be your problem than the scoop opening being to small.
No factory type scoops work for ram air. The opening has to be in the boundry layer which is a few inches higher than the factory scoop opening. As the car moves forward the front of the vehicle diverts air up and over the scoop and very little into it.
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Re: Sealed Hood to Air Pan
[Re: BobR]
#917168
01/31/11 01:48 PM
01/31/11 01:48 PM
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Joined: Jun 2009
Posts: 644
Minnesota
Barnstorm
mopar
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mopar
Joined: Jun 2009
Posts: 644
Minnesota
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Frito is right...not many if any SS/AH are sealed. Simple test..tape several stips of yarn in front of your scoop and have someone observe or camcorder the way it behaves at speed.
The little old lady from Pasadena is back!
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Re: Sealed Hood to Air Pan
[Re: Barnstorm]
#917169
01/31/11 09:14 PM
01/31/11 09:14 PM
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Joined: Nov 2009
Posts: 3,410
Belpre,Ohio
CHAPPER
master
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master
Joined: Nov 2009
Posts: 3,410
Belpre,Ohio
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I am having a hard time getting my head wrapped around all this info. Some say the stock scoops will not let enough air into the carb,,,? My question to this is,,,why do all the Super Stock cars run them? I realize they are correct for the car. If they don't allow enough air in,,how do they run so good? Record holding cars are the opitome of research and development. If the factory hood scoops don't work,,what are they doing to make them work? They can't be raising them up to get into the 'good air'..."straight line between roof and leading hood edge"... If the factory scoops aren't doing any good,,why don't all the people run the cowl hoods that all the Mopar people hate? I don't really care about what is 'correct' or 'legal', I am just trying to get some cooler, fresh air into my carb. I am not trying to be a wise act,,just trying to figure out some things. I will be doing some more testing when the weather gets better and hope to get this hood/scoop thing figured out so it will work like it should. As for the SS/HA cars having sealed scoops, they would probably lift the hood off or rip the scoop off if they were sealed!! I still can't imagine how they are NOT having air problems with all the air going over/around the carbs,,,UNLESS,,like others have said..there isn't enough air going into the scoop...? Maybe they are losing some ET..??..I doubt this very much! 
If you like drag racing, support your local track.
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Re: Sealed Hood to Air Pan
[Re: CHAPPER]
#917170
01/31/11 11:02 PM
01/31/11 11:02 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
I am having a hard time getting my head wrapped around all this info.
Some say the stock scoops will not let enough air into the carb,,,?
My question to this is,,,why do all the Super Stock cars run them?
I realize they are correct for the car. If they don't allow enough air in,,how do they run so good? Record holding cars are the opitome of research and development. If the factory hood scoops don't work,,what are they doing to make them work? They can't be raising them up to get into the 'good air'..."straight line between roof and leading hood edge"... If the factory scoops aren't doing any good,,why don't all the people run the cowl hoods that all the Mopar people hate? I don't really care about what is 'correct' or 'legal', I am just trying to get some cooler, fresh air into my carb. I am not trying to be a wise act,,just trying to figure out some things. I will be doing some more testing when the weather gets better and hope to get this hood/scoop thing figured out so it will work like it should. As for the SS/HA cars having sealed scoops, they would probably lift the hood off or rip the scoop off if they were sealed!!
I still can't imagine how they are NOT having air problems with all the air going over/around the carbs,,,UNLESS,,like others have said..there isn't enough air going into the scoop...? Maybe they are losing some ET..??..I doubt this very much!
For testing... take some cardboard and tape it to
the current scoop but make the front longer so its
closer to the front of the hood... tape it to the
hood to simulate a sealed scoop then run it(come
warmer weather)... I dont know what the SS guys are
doing... I've never looked but maybe they dont seal
it... or they pull in air via tubes 
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Re: Sealed Hood to Air Pan
[Re: Eric]
#917172
01/31/11 11:28 PM
01/31/11 11:28 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
I picked up close to 2 tenths with the Arrow...
I picked up also Eric... but our scoops are up in
the air flow
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Re: Sealed Hood to Air Pan
[Re: MR_P_BODY]
#917173
02/01/11 12:28 AM
02/01/11 12:28 AM
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Joined: Jul 2005
Posts: 336
Creston, Iowa
340man4ever
enthusiast
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enthusiast
Joined: Jul 2005
Posts: 336
Creston, Iowa
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As to SS/AH running them- they can't per rules, otherwise they would run them  Pro Stock experiments with these setups almost weekly (i.e. scoop design, shape etc). What's that tell ya?  My reading of the Mopar Bible hints that in general terms a properly functioning sealed scoop set up should result in 1 to 1.5mph gain in the 1/4 mile (your results may vary) 
Last edited by 340man4ever; 02/01/11 12:44 AM.
Curator at Adams County Speed Shop
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Re: Sealed Hood to Air Pan
[Re: CHAPPER]
#917174
02/01/11 12:40 AM
02/01/11 12:40 AM
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Joined: Oct 2004
Posts: 8,166
Left Coast
BobR
master
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master
Joined: Oct 2004
Posts: 8,166
Left Coast
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Quote:
I am having a hard time getting my head wrapped around all this info.
Some say the stock scoops will not let enough air into the carb,,,?
My question to this is,,,why do all the Super Stock cars run them?
I realize they are correct for the car. If they don't allow enough air in,,how do they run so good? Record holding cars are the opitome of research and development. If the factory hood scoops don't work,,what are they doing to make them work? They can't be raising them up to get into the 'good air'..."straight line between roof and leading hood edge"... If the factory scoops aren't doing any good,,why don't all the people run the cowl hoods that all the Mopar people hate? I don't really care about what is 'correct' or 'legal', I am just trying to get some cooler, fresh air into my carb. I am not trying to be a wise act,,just trying to figure out some things. I will be doing some more testing when the weather gets better and hope to get this hood/scoop thing figured out so it will work like it should. As for the SS/HA cars having sealed scoops, they would probably lift the hood off or rip the scoop off if they were sealed!!
I still can't imagine how they are NOT having air problems with all the air going over/around the carbs,,,UNLESS,,like others have said..there isn't enough air going into the scoop...? Maybe they are losing some ET..??..I doubt this very much!
Who said they don't allow enough air into the carb? There is no ram effect but that's much different than what you just said. That's why the SS/H cars don't seal them. Some scoop designs cause turbulence around the carb and screw the fuel signal up. Some of the stuff out of the factory was for show and a little for cool air.
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Re: Sealed Hood to Air Pan
[Re: larry890]
#917176
02/01/11 07:38 AM
02/01/11 07:38 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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It very well may be the added height thats helping you, I would like to do a study on different scoops to see what effect each has.... I'll start another post
Last edited by MR_P_BODY; 02/01/11 08:51 AM.
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Re: Sealed Hood to Air Pan
[Re: 340man4ever]
#917177
02/01/11 08:11 AM
02/01/11 08:11 AM
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Joined: Dec 2008
Posts: 1,607
KYbywayof WV
Frito
top fuel
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top fuel
Joined: Dec 2008
Posts: 1,607
KYbywayof WV
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Quote:
As to SS/AH running them- they can't per rules, otherwise they would run them
Pro Stock experiments with these setups almost weekly (i.e. scoop design, shape etc). What's that tell ya?
My reading of the Mopar Bible hints that in general terms a properly functioning sealed scoop set up should result in 1 to 1.5mph gain in the 1/4 mile (your results may vary)
I am fairly familiar with the SS/AH rules, I must have missed this part!!!
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Re: Sealed Hood to Air Pan
[Re: BobR]
#917179
02/01/11 10:17 AM
02/01/11 10:17 AM
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Joined: Nov 2009
Posts: 3,410
Belpre,Ohio
CHAPPER
master
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master
Joined: Nov 2009
Posts: 3,410
Belpre,Ohio
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Quote:
Quote:
I am having a hard time getting my head wrapped around all this info.
Some say the stock scoops will not let enough air into the carb,,,?
My question to this is,,,why do all the Super Stock cars run them?
I realize they are correct for the car. If they don't allow enough air in,,how do they run so good? Record holding cars are the opitome of research and development. If the factory hood scoops don't work,,what are they doing to make them work? They can't be raising them up to get into the 'good air'..."straight line between roof and leading hood edge"... If the factory scoops aren't doing any good,,why don't all the people run the cowl hoods that all the Mopar people hate? I don't really care about what is 'correct' or 'legal', I am just trying to get some cooler, fresh air into my carb. I am not trying to be a wise act,,just trying to figure out some things. I will be doing some more testing when the weather gets better and hope to get this hood/scoop thing figured out so it will work like it should. As for the SS/HA cars having sealed scoops, they would probably lift the hood off or rip the scoop off if they were sealed!!
I still can't imagine how they are NOT having air problems with all the air going over/around the carbs,,,UNLESS,,like others have said..there isn't enough air going into the scoop...? Maybe they are losing some ET..??..I doubt this very much!
Who said they don't allow enough air into the carb? There is no ram effect but that's much different than what you just said. That's why the SS/H cars don't seal them. Some scoop designs cause turbulence around the carb and screw the fuel signal up. Some of the stuff out of the factory was for show and a little for cool air.
I believe you said in your previous post ...air is diverted up/over the scoop with very little air going in...I took 'very little' to mean inadequate. Maybe you were meaning not enough for a ram effect. I am not necessarily looking for 'ram' effect, just cooler air than is under the hood and not have the entering air cause problems with the carb. I am positive that the air is disturbing the fuel signal, just trying to figure out what it is actually doing to it.
If you like drag racing, support your local track.
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Re: Sealed Hood to Air Pan
[Re: CHAPPER]
#917180
02/01/11 10:59 AM
02/01/11 10:59 AM
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Joined: Sep 2003
Posts: 2,008
Sweet Home Alabama
MRMOPAR622
top fuel
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top fuel
Joined: Sep 2003
Posts: 2,008
Sweet Home Alabama
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Looking a the picture in Frito's post it looks as if the base of the carbs. might be above the hood level. That may be the reason,or there is just not enough space when they are sealed to the hood. If I were you I would not go with the factory style hood scoops. They look the best on the cars,but they may not be the best. I put a cowl hood on my 67 R/T and pick up another .05-.06 over the factory Hemi style scoop that picked up about .06 in the 1/8. In all I picked up a little over a .10 with the proper hood scoop in the 1/8 mile.
"To Be The Man'You Have Got To Beat The Man"
"T/D and Pro-Bracket Racer"
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Re: Sealed Hood to Air Pan
[Re: larry890]
#917181
02/01/11 11:23 AM
02/01/11 11:23 AM
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Joined: Oct 2004
Posts: 8,166
Left Coast
BobR
master
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master
Joined: Oct 2004
Posts: 8,166
Left Coast
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Quote:
I have a six pack scoop on my gtx, it is a little taller than stock. it has a pan, if i take it off it runs .10 slower no matter the temp.
If it isn't in the boundry layer there is no positive pressure at the carb.
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Re: Sealed Hood to Air Pan
[Re: CHAPPER]
#917182
02/01/11 11:23 AM
02/01/11 11:23 AM
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Joined: Oct 2003
Posts: 7,506
Az
Crizila
master
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master
Joined: Oct 2003
Posts: 7,506
Az
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Quote:
Quote:
Quote:
I am having a hard time getting my head wrapped around all this info.
Some say the stock scoops will not let enough air into the carb,,,?
My question to this is,,,why do all the Super Stock cars run them?
I realize they are correct for the car. If they don't allow enough air in,,how do they run so good? Record holding cars are the opitome of research and development. If the factory hood scoops don't work,,what are they doing to make them work? They can't be raising them up to get into the 'good air'..."straight line between roof and leading hood edge"... If the factory scoops aren't doing any good,,why don't all the people run the cowl hoods that all the Mopar people hate? I don't really care about what is 'correct' or 'legal', I am just trying to get some cooler, fresh air into my carb. I am not trying to be a wise act,,just trying to figure out some things. I will be doing some more testing when the weather gets better and hope to get this hood/scoop thing figured out so it will work like it should. As for the SS/HA cars having sealed scoops, they would probably lift the hood off or rip the scoop off if they were sealed!!
I still can't imagine how they are NOT having air problems with all the air going over/around the carbs,,,UNLESS,,like others have said..there isn't enough air going into the scoop...? Maybe they are losing some ET..??..I doubt this very much!
Who said they don't allow enough air into the carb? There is no ram effect but that's much different than what you just said. That's why the SS/H cars don't seal them. Some scoop designs cause turbulence around the carb and screw the fuel signal up. Some of the stuff out of the factory was for show and a little for cool air.
I believe you said in your previous post ...air is diverted up/over the scoop with very little air going in...I took 'very little' to mean inadequate. Maybe you were meaning not enough for a ram effect. I am not necessarily looking for 'ram' effect, just cooler air than is under the hood and not have the entering air cause problems with the carb. I am positive that the air is disturbing the fuel signal, just trying to figure out what it is actually doing to it.
Getting cooler outside air in verses under hood air is always a winner. That part is a no brainer. If in doing so you are creating so much turbulance that it has a negative effect on performance and or you have to run a filter to fix it, that is another issue that you need to address. You shouldn't be sacrificing cool air ( or restricting flow )to fix a turbulance problem. Your scoop opening needs to be OUT of the boundery layer, not in it. Rear facing scoops usually solve that problem. They also afford a longer run ( usually ) between the scoop opening and the carb. This also will help smooth out the air as it enters the carb. Other issues that can creat problems are big cammed engines with lots of reversion going on and the carbs being too close to the top of the scoop. The more space you have between the top of the scoop and the carb opening the less turbulance you will have. Above all, get outside air in. I am not necessarily an advocate of year facing scoops ( although I run one ), but they can solve a lot of turbulance problems, without having to put the scoop opening way high to get away from turbulant air. I would also say that if my car ran fast enough ( and it don't ) to gain anything from pressure ( above 14.7 ) I would run a front facing scoop.
Fastest 300
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Re: Sealed Hood to Air Pan
[Re: CHAPPER]
#917183
02/01/11 11:27 AM
02/01/11 11:27 AM
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Joined: Oct 2004
Posts: 8,166
Left Coast
BobR
master
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master
Joined: Oct 2004
Posts: 8,166
Left Coast
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Quote:
Quote:
Quote:
I am having a hard time getting my head wrapped around all this info.
Some say the stock scoops will not let enough air into the carb,,,?
My question to this is,,,why do all the Super Stock cars run them?
I realize they are correct for the car. If they don't allow enough air in,,how do they run so good? Record holding cars are the opitome of research and development. If the factory hood scoops don't work,,what are they doing to make them work? They can't be raising them up to get into the 'good air'..."straight line between roof and leading hood edge"... If the factory scoops aren't doing any good,,why don't all the people run the cowl hoods that all the Mopar people hate? I don't really care about what is 'correct' or 'legal', I am just trying to get some cooler, fresh air into my carb. I am not trying to be a wise act,,just trying to figure out some things. I will be doing some more testing when the weather gets better and hope to get this hood/scoop thing figured out so it will work like it should. As for the SS/HA cars having sealed scoops, they would probably lift the hood off or rip the scoop off if they were sealed!!
I still can't imagine how they are NOT having air problems with all the air going over/around the carbs,,,UNLESS,,like others have said..there isn't enough air going into the scoop...? Maybe they are losing some ET..??..I doubt this very much!
Who said they don't allow enough air into the carb? There is no ram effect but that's much different than what you just said. That's why the SS/H cars don't seal them. Some scoop designs cause turbulence around the carb and screw the fuel signal up. Some of the stuff out of the factory was for show and a little for cool air.
I believe you said in your previous post ...air is diverted up/over the scoop with very little air going in...I took 'very little' to mean inadequate. Maybe you were meaning not enough for a ram effect. I am not necessarily looking for 'ram' effect, just cooler air than is under the hood and not have the entering air cause problems with the carb. I am positive that the air is disturbing the fuel signal, just trying to figure out what it is actually doing to it.
Gravity will feed the carb assuming adequate open frontal area which I assume you have. There will be no greater than gravity pressurization, however, unless the scoop opening is in the boundry layer and even then an improperly designed boundry layer scoop will cause more drag that will not be compensated for by any additional power.
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