Hood Scoop issues

Ed Sroka · 09-11-2012, 07:58 PM

I've performed CFD analysis on several scoop designs. Many with marginal results.

If you send me the details of the scoop, its position relative to the body/cage and let me know which scoop tray and carburetor you're using, I may be able to offer some feedback.

There are many concerns that exist here. It's likely a few scoop designs can cost in excess of 40 usable horsepower. The concerns with pressure and velocity begin externally and are exacerbated at the point of carburetor entry.

You can send a PM if you like.

I can provide information on the proper air filter choice as well.

SST159 · 09-12-2012, 11:04 PM

Ed,
Thanks for the help.
I will PM you with some info as soon as I can.
Thanks.

jmarkaudio · 09-17-2012, 03:04 PM

Try tying the vents together like the picture in the link. If the scoop upset the pressure at the bowl vents it can send it lean.

http://i287.photobucket.com/albums/l...udio/Flute.jpg

SST159 · 09-18-2012, 01:57 PM

yes, I did tie the vents together and it still pops. I am currently fabricating a full pan to totally seal off the scoop tight along with sealing off the open back of the scoop at the windsheild. hopefully I can get out to test next week. If that does not correct it then next step would be to try a filter. Problem is there are too many filter options to select from. What I cannot figure out is I see many racers run these hood scoops with no pan and wide open in the back and have no problems. Perhaps the air turbulance does not affect a dominator as it does the 4150. I think my car is pissed off at me for something. Bad enough when the wife gets pissed but when the race car does??? Thanks for the suggestions and still welcome any more if available.

nickh · 09-19-2012, 07:31 PM

Drew FYI I got the UNI Filter shipment in.

bricki · 09-24-2012, 07:05 AM

Hi sst159 you say you went up 4 jet sizes what jets were they i have
done 4 jet sizes up with holley jets with no change then used maxi
and precision jets and got a result jets aint jets.
cheers.

SST159 · 09-24-2012, 04:21 PM

Went from 82 jet to 86 in the 950 HP carb which is square jet, then I also put my other carb on which is an 850 set up 76 and 82 jet with power valve and it did the same thing.
I really think it is the scoop and the way the air is turbulant as the car goes down track. I fabricated a new pan and sealed off the entire pan and carb including sealing of the back of the scoop. Heading out to test in a few weeks and we shall see. if that does not work then the next step is a filter. Never used the maxi jet before. What is the deal on them?

09-11-2012, 07:58 PM	#1
Ed Sroka Junior Member Join Date: Aug 2003 Location: Lake Zurich, IL Posts: 22 Likes: 0 Liked 1 Time in 1 Post	Re: Hood Scoop issues I've performed CFD analysis on several scoop designs. Many with marginal results. If you send me the details of the scoop, its position relative to the body/cage and let me know which scoop tray and carburetor you're using, I may be able to offer some feedback. There are many concerns that exist here. It's likely a few scoop designs can cost in excess of 40 usable horsepower. The concerns with pressure and velocity begin externally and are exacerbated at the point of carburetor entry. You can send a PM if you like. I can provide information on the proper air filter choice as well.

09-12-2012, 11:04 PM	#2
SST159 Member Join Date: Jul 2005 Posts: 315 Likes: 5 Liked 20 Times in 16 Posts	Re: Hood Scoop issues Ed, Thanks for the help. I will PM you with some info as soon as I can. Thanks. __________________ Drew Wonderly SST 159

09-17-2012, 03:04 PM	#3
jmarkaudio Junior Member Join Date: Apr 2008 Posts: 83 Likes: 0 Liked 0 Times in 0 Posts	Re: Hood Scoop issues Try tying the vents together like the picture in the link. If the scoop upset the pressure at the bowl vents it can send it lean. http://i287.photobucket.com/albums/l...udio/Flute.jpg

09-18-2012, 01:57 PM	#4
SST159 Member Join Date: Jul 2005 Posts: 315 Likes: 5 Liked 20 Times in 16 Posts	Re: Hood Scoop issues yes, I did tie the vents together and it still pops. I am currently fabricating a full pan to totally seal off the scoop tight along with sealing off the open back of the scoop at the windsheild. hopefully I can get out to test next week. If that does not correct it then next step would be to try a filter. Problem is there are too many filter options to select from. What I cannot figure out is I see many racers run these hood scoops with no pan and wide open in the back and have no problems. Perhaps the air turbulance does not affect a dominator as it does the 4150. I think my car is pissed off at me for something. Bad enough when the wife gets pissed but when the race car does??? Thanks for the suggestions and still welcome any more if available. __________________ Drew Wonderly SST 159

09-19-2012, 07:31 PM	#5
nickh Senior Member Join Date: Sep 2010 Location: Houston,Texas Posts: 819 Likes: 3,535 Liked 642 Times in 192 Posts	Re: Hood Scoop issues Drew FYI I got the UNI Filter shipment in.

09-24-2012, 07:05 AM	#6
bricki Junior Member Join Date: Aug 2012 Posts: 14 Likes: 0 Liked 0 Times in 0 Posts	Re: Hood Scoop issues Hi sst159 you say you went up 4 jet sizes what jets were they i have done 4 jet sizes up with holley jets with no change then used maxi and precision jets and got a result jets aint jets. cheers.

09-24-2012, 04:21 PM	#7
SST159 Member Join Date: Jul 2005 Posts: 315 Likes: 5 Liked 20 Times in 16 Posts	Re: Hood Scoop issues Went from 82 jet to 86 in the 950 HP carb which is square jet, then I also put my other carb on which is an 850 set up 76 and 82 jet with power valve and it did the same thing. I really think it is the scoop and the way the air is turbulant as the car goes down track. I fabricated a new pan and sealed off the entire pan and carb including sealing of the back of the scoop. Heading out to test in a few weeks and we shall see. if that does not work then the next step is a filter. Never used the maxi jet before. What is the deal on them? __________________ Drew Wonderly SST 159