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Do folks open up an opening behind the grills to let cold air into the engine bay ? While the engine is far from sealed, there clearly is not a great path of cold air to the carbs....Since I am restoring the car and everything is apart, I have been wondering if folks generally make small modifications like this (as is done with so many other cars). If so, do folks have any pictures ?

Also while I have read about the dealer installed factory scoop (ram air), whereby the hood was cut, it appears the bigger challenge is the fake grill. How did the dealer open up the fake grill in the top center of the hood (sorry don't know what to call it)? Thanks
 

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Do folks open up an opening behind the grills to let cold air into the engine bay ? While the engine is far from sealed, there clearly is not a great path of cold air to the carbs....Since I am restoring the car and everything is apart, I have been wondering if folks generally make small modifications like this (as is done with so many other cars). If so, do folks have any pictures ?

Also while I have read about the dealer installed factory scoop (ram air), whereby the hood was cut, it appears the bigger challenge is the fake grill. How did the dealer open up the fake grill in the top center of the hood (sorry don't know what to call it)? Thanks
I have seen some modify their closed scoops using a dremel tool to cut the center area away. As far as an opening behind the grilles, the radiator of my '70 is just behind the grilles, plenty of air running through.
 

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Discussion Starter #3 (Edited)
I have seen some modify their closed scoops using a dremel tool to cut the center area away. As far as an opening behind the grilles, the radiator of my '70 is just behind the grilles, plenty of air running through.
Yes but that air is quite a bit hotter than the ambient air (maybe)....My thought was to open a hole up on both side to direct cold air right into the engine bay.
 

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"How did the dealer open up the fake grill in the top center of the hood (sorry don't know what to call it)?"

I believe the technical term is "hood insert." The cold air or Ram Air inserts were cast as open, just like the non-RA inserts were cast as closed. So two different factory offerings with regards to the hood inserts.

What is your reasoning & goal in directing outside air into the engine bay? Quite a few offerings on Ebay that might give you some ideas. https://www.ebay.ca/sch/i.html?_sacat=0&_nkw=bumper+air+intake
 

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Discussion Starter #5
"How did the dealer open up the fake grill in the top center of the hood (sorry don't know what to call it)?"

I believe the technical term is "hood insert." The cold air or Ram Air inserts were cast as open, just like the non-RA inserts were cast as closed. So two different factory offerings with regards to the hood inserts.

What is your reasoning & goal in directing outside air into the engine bay? Quite a few offerings on Ebay that might give you some ideas. https://www.ebay.ca/sch/i.html?_sacat=0&_nkw=bumper+air+intake
Jim - Different hood inserts makes sense as it looked too hard to cut cleanly! My thought was that I could make an opening to the right and left of the radiator and cold air would be directed into the engine bay, hopefully reduce IAT a bit, and reduce the chance of pre detonation / increase HP. While cold air intakes are great, I would have to literally run hoses or tubing up to the carbs and have the carbs isolated from the engine bay air (which I won't do), so I guess it is pointless or would yield little benefit.

Back to wrenching on the electrical system :) and POR15 work. I am installing the MAD Electrical Start Em' Up kit and probably the light and accessory relays as well and almost done with the POR15 on the floors.
 

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Jim - Different hood inserts makes sense as it looked too hard to cut cleanly! My thought was that I could make an opening to the right and left of the radiator and cold air would be directed into the engine bay, hopefully reduce IAT a bit, and reduce the chance of pre detonation / increase HP. While cold air intakes are great, I would have to literally run hoses or tubing up to the carbs and have the carbs isolated from the engine bay air (which I won't do), so I guess it is pointless or would yield little benefit.

Back to wrenching on the electrical system :) and POR15 work. I am installing the MAD Electrical Start Em' Up kit and probably the light and accessory relays as well and almost done with the POR15 on the floors.
OK, got it. The "Ram Air" systems used by many makers in various forms were in my opinion a little more than the visual looks and bragging rights. It did help to some extent to bring cooler outside air into the engine, not the engine bay, and this was usually at higher speeds.

As long as the hood is in place, it will trap hot engine temps. Mopars seem to run hot under the hood in my opinion and on my 1973 Fury the factory installed seals (flat 1/4" flexible panels) strategically behind the grille to seal off some of the surrounding open areas and channel/force air flow through the radiator area. I think their nose design with its inner fender panels creates more of a box enclosure that traps more heat than lets say a GM product with its inner fender well design and a bunch more open areas for hot temps to escape.

To keep engine temps down, just run a good cooling system using an aluminum radiator, fan shroud, good fan, and a 160 degree thermostat. Correct carb settings (not too lean) and proper ignition timing are also part of a cool running engine.

Of course there is the "old school" remove the hood completely to show off your engine and chromed accessories or what some racers do, lift the rear of the hood with spacers high enough to create airflow out the back at the windshield. :thumbsup:
 

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Discussion Starter #7
Jim - Interesting I still can't seem to find anyone that sells the open inserts...I would have thought this was a cold air kit (ram air pan + inserts)....Oh well...
 

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No one sells an open insert as it is easy enough to modify any of the aftermarket closed hood inserts. Fairly simple job with the right tools. If you can't do it yourself, take it to a machine shop and let them do it.

You will also have to cut your under hood bracing as well as the bracing behind the insert.
 

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Ah so buy an aftermarket insert and cut that....smart....thanks Jim (again)....

I'd like to buy you a beer, but have a feeling you are no where close....How about mail you some local micro brews ?
 

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Their description says that the insert does not fit an original hood so well and may need some work. Wish they had a picture of it on an original hood. I looked at the OPGI catalog and they do not offer an open insert, but have the closed one. There was no note as to how it fit. Maybe the closed insert is a better fit? They claim their 1965-67 hood is stamped as original, so an email might confirm their fit on the closed insert and then go from there and open it up.

The other option, which may be the best route to go, is an original insert. There is one up on Ebay right now starting bid $40 (plus shipping). Note the sellers comment about its fit on the aftermarket GTO hood. https://www.ebay.ca/itm/Original-1965-1967-Pontiac-GTO-Hood-Scoop-Insert/222826485089?hash=item33e17e5561:g:nTUAAOSwEW9ab3~M&vxp=mtr
 

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Discussion Starter #12
I think I'm just going to cut my original insert - cut the back off using a cutting wheel. Seems silly to spend $100 for a part that doesn't fit well. Thoughts ?
 

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I think I'm just going to cut my original insert - cut the back off using a cutting wheel. Seems silly to spend $100 for a part that doesn't fit well. Thoughts ?
Why not? It is what I would do. The next buyer, if he doesn't like it, can purchase a used closed insert, right?
 

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What started me thinking about this was a short video clip about the Royal Bobcat. It mentions adding a ram air set up with the scoop opened up. I believe you can find aftermarket ram air set ups for a 65. I just wanted to open up the scoop. More for looks than anything.
 

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Discussion Starter #15
So I have cut the inserts and plate right behind the inserts so that air flows into the carbs. That said, I have not cut the support bracing on the underside of the hood. I am wondering if others have done the same or if we really need to cut the bracing ? It appears the rear foam pinches, but i was planning on just trimming the foam a bit (removing ~1/4" at a time). Thoughts ?

I am also thinking about cutting two small holes to the left and right of the radiator and running air intake hose up to the carbs. (I won't do this if I can't make it look great.) Thanks
 

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I bought my car a few weeks ago. It has FiTech fuel injection so I can read the intake air temp. Last time I checked, on a 100+ degree day, IAT was 155. Ouch! I'm going to open up my scoop and see what happens.
 

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I bought my car a few weeks ago. It has FiTech fuel injection so I can read the intake air temp. Last time I checked, on a 100+ degree day, IAT was 155. Ouch! I'm going to open up my scoop and see what happens.

Keep us posted, it will be interesting to see what the drop is.
 

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Keep us posted, it will be interesting to see what the drop is.
Since my car is a clone I suspect my hood is a reproduction because when I slide my hand on the underside of the scoop forward I can feel the back of the insert without any apparent obstruction. I take it you can't do this with an original hood(?).
 

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Since my car is a clone I suspect my hood is a reproduction because when I slide my hand on the underside of the scoop forward I can feel the back of the insert without any apparent obstruction. I take it you can't do this with an original hood(?).
Not sure what you are referencing. The factory hood scoop is closed off - it'll look like a grille at the back area inside where it is closed off.

When adding the Ram Air option, the scoop is open and you can see right into it. The hood bracing right behind it needs to be trimmed slightly. This allows outside air to enter. The carb pan for the Ram Air option seals against the underside of the hood - sealing off th heat from the engine while allowing cooler outside air to flow in. Problems can occur when it rains. No way to close off the open scoop. One of the reasons the later RA hoods had a control cable and an opening/closing flapper in the scoop.
 
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