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over the hood\roof scoops by lowtrickry
Started on: 06-03-2014 03:02 AM
Replies: 7 (489 views)
Last post by: James Bond 007 on 06-04-2014 05:09 PM
lowtrickry
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Report this Post06-03-2014 03:02 AM Click Here to See the Profile for lowtrickryClick Here to Email lowtrickrySend a Private Message to lowtrickryEdit/Delete MessageReply w/QuoteDirect Link to This Post
Anyone still making the dual over the hood/roof decklid scoops or anyone have a set for sale?
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Dennis LaGrua
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Report this Post06-03-2014 08:16 AM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
If the scoops that you speak of are the pair that fit over the air exhaust grills, I would not recommend using them. The cooling of the engine compartment relies on air underneath the engine to come up and over the powertrain to cool it. The hot air then exits from the air grills. When the car is moving, these over the roof scoops force air down the grills with pressure and prevent venting. Those scoops may impede the natural air flow used to cool the engine. I believe that they are no longer made..
Now if you are referring to the over the roof scoop centered on the deck lid and used on the Indy, IMO that is a better idea.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
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DKcustoms
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Report this Post06-03-2014 04:42 PM Click Here to See the Profile for DKcustomsSend a Private Message to DKcustomsEdit/Delete MessageReply w/QuoteDirect Link to This Post
I disagree with Dennis, almost completely.

Sure, the natural airflow is as he described.

But, forcing air down those vents over the engine would just force that air out the bottom of the car at speed, both in front of and behind the motor.
If you are really concerned about it, with the over-the-roof scoops you can put a decklid vent in to let the extra air out, like many people have done.
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Sage
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Report this Post06-03-2014 05:31 PM Click Here to See the Profile for SageClick Here to Email SageSend a Private Message to SageEdit/Delete MessageReply w/QuoteDirect Link to This Post
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Dennis LaGrua
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Report this Post06-03-2014 10:26 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by DKcustoms:

I disagree with Dennis, almost completely.

Sure, the natural airflow is as he described.

But, forcing air down those vents over the engine would just force that air out the bottom of the car at speed, both in front of and behind the motor.
If you are really concerned about it, with the over-the-roof scoops you can put a decklid vent in to let the extra air out, like many people have done.


Vent on decklid would solve problem. As for your claim that air into the scoops would push the hot air downward and underneath the powertrain ; lets not forget that the Fiero was designed to have an upward airflow in the engine compartment as the car moves. Tie a ribbon on each grill and watch. Therefore the air pressure going into the over the roof scoops would have to be greater than that normally flowing upwards to achieve cooling. I do believe that there is logic in my explanation but you certainly have a right to disagree.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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rogergarrison
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Report this Post06-04-2014 08:50 AM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
I agree 100% with Dennis. The over the roof scoops going into the air exhaust vents is a bad idea unless you never drive on freeway. The air would be constantly fighting. Design is trying to suck the air in at the bottom and pushing it out the top vents to cool the engine bay. The scoops are trying to force the heated air right back down. Its a toss up who wins. Its like turning on a garden hose and trying to use another hose at the open end to push the water back into the faucet. Adding another vent of equal area to allow the hot air to escape would probably fix the problem. You WANT an easy free flow of air with no restriction or opposition.

Heat naturally rises, so it was designed to take in fresh air at the bottom and exit at the top...dont work the other way. (well maybe it would if you find room to put in a couple of home box fans..blowing downward.)

[This message has been edited by rogergarrison (edited 06-04-2014).]

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Lou6t4gto
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Report this Post06-04-2014 03:38 PM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
I Agree with Dennis, if the vents were "Designed to let air OUT", WHY would you try to force Air IN ? To make it LOOK "Cool" ? imo airodynamicly unsound, and un needed.
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James Bond 007
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Report this Post06-04-2014 05:09 PM Click Here to See the Profile for James Bond 007Send a Private Message to James Bond 007Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by lowtrickry:

Anyone still making the dual over the hood/roof decklid scoops or anyone have a set for sale?


Are you talking about cooling the engine compartment or ram injection. My investigation into ram injection, shows that, it only works over 70+ MPH, with some benifit.

[This message has been edited by James Bond 007 (edited 06-04-2014).]

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