Hood scoops 71 Mach 1

[DAverkamp]

In that case, it might actually improve flow through the radiator! It certainly helps to understand the boundary conditions. Considering the cross sectional areas involved, the effect is probably minimal whatever it may be.

I wonder if there are any youtube videos of 71-73's in a wind tunnel. That would be pretty cool to check out.

IMO, not sure about that as the rpm’s increase, the stock fan blades “spool up” and expand in towards radiator face and their OD is well past the ID of the shroud creating x?cfm of flow through it which I doubt would be affected by any air going into the open ducts on the hood and swirling around unmanaged. I could envision plug wires, accessorie wires, vacuum lines/hoses, etc. being whipped around in the engine bay like crazy with the intake air not being funneled into to a “functional” cold air box pumping directly into the intake manifold. A set of go pros mounted by the battery and WS washer reservoir for an experimental video would be cool to see if any of you that are running open ducts would take that on.

 

[jscott]

That is one of the reasons all Ram Air cars have the twist locks. They are a secondary functional latch for the additional force on the hood.
. ;-)Kcmash

Really? My ram air hood does not have twist locks and I am assuming it is the original hood???

 

[Fabrice]

@jscott
"install a electric vacuum switch so you can open and close flappers at will."
Do you have a link to an electric actuator/motor or a circuit print? So far all circuits i've found are keeping the motor under current when open.
I want make flaps that open on key on and close on key off for ages.

" My ram air hood does not have twist locks and I am assuming it is the original hood???"
They help a bit but if your hood is well adjusted, laying firmly on the 2 mushrooms on each side on top of radiator support. The hood latch will keep the hood in place with no efforts. Even if they of course help, they are mainly sporty aesthetic thingies. so don't worry.

I think in general with any hood type on our cars, that what matters most is the front suspension, in lots of original setup the hood/nose of car is too high
and when your drive, the hood tries to lift vs push down. Another thing to think about is close the front valance on 71-72 models.

 

[jscott]

this is what I use for my flappers, with power off they open so I control them with a switch.

https://smile.amazon.com/VACUUM-SOL...id+valve,+2+port+w/bracket+12v,aps,116&sr=8-3

 

[kcmash]

Really? My ram air hood does not have twist locks and I am assuming it is the original hood???

I don’t have any Ford Documentation on that, just personal experience.

When we had these cars as daily drivers in the 80’s, several of us opened the scoops up. I had one friend lose his hood on the highway as the primary latch failed, the hood flew open and buried the back of the hood into the base of the windshield.

I was running mine with the scoops open and no twirl locks as I ran up and down the highway. I noticed my hood starting to vibrate and lift. I found that it tore the metal on the base of the hood latch bracket, so the whole latch and support were rocking backward. I feel lucky I caught that.

I figure since all the original Ram-Air equipped cars I have seen on all Mustangs tend to have factory hood pins of some type, there was probably a design justification for the hood pins.


Kcmash

 

[timachone]

Really? My ram air hood does not have twist locks and I am assuming it is the original hood???

In 71/72 you had to order ram air to get the twist locks and the tutone on your NACA hood, 351c and 429. On the Boss both was standard.

In 73 you could order the twist locks and tutone treatment separately, ram air was only available for the 2V cars.

The NACA hood was standard for all 71-73 Mach 1 on 351 or larger engines, a no cost option on 302 powered Mach 1. If you did not get ram air your NACA hood was body color.

The NACA hood was also standard on the more powered cars like 351c 4V's or 429's, of course the Boss. And some special Models like the Spring Special in 1972.

 

[basstrix]

IMO, not sure about that as the rpm’s increase, the stock fan blades “spool up” and expand in towards radiator face and their OD is well past the ID of the shroud creating x?cfm of flow through it which I doubt would be affected by any air going into the open ducts on the hood and swirling about unmanaged. I could envision plug wires, accessorie wires, vacuum lines/hoses, etc. being whipped around in the engine bay like crazy with the intake air not being funneled into a “functional” cold air box pumping directly into the intake manifold. A set of go pros mounted by the battery and WS washer reservoir for an experimental video would be cool to see if any of you that are running open ducts would take that on.

It all depends on what the pressures are at the boundaries.

I like the idea of a gopro...I'm actually considering something like that to observes what's going on with carburetors.

You could do a simple test by attaching streamers at various locations just to see which direction air is moving. My hood is currently removed or I'd consider doing it.

 

[jscott]

Well I was thinking of installing them and now with more reason. I saw this video, does not seem too difficult except the scary part of drilling the big holes in the hood. Who has done this? Easy, hard?

 

[vintageman]

Well I was thinking of installing them and now with more reason. I saw this video, does not seem too difficult except the scary part of drilling the big holes in the hood. Who has done this? Easy, hard?

Very easy, to do. I used a hole saw on a piece of wood. Cut it out, wrapped tape around it so that it was snug in the hole on the bottom side of the hood. I then used a drill bit in the center hole on the wood to make my initial hole in the hood. Closed the hood, taped over the area that would be drilled out with the hole saw and then drilled out with the hole saw. Not too bad of a job at all, pretty easy. But as you say, the first second or two with the hole saw actually cutting the hood was kinda scary. Good luck.

Tom

 

[timachone]

Well I was thinking of installing them and now with more reason. I saw this video, does not seem too difficult except the scary part of drilling the big holes in the hood. Who has done this? Easy, hard?

Done without the wood, measured exactly, drilling from the inside, scared, but went easy. Filed around the cut and test fitted the locks so they have a little bit room in the hole and are not too tight in there. Then paint on the edge and install - or paint the whole hood as I did...

 

[jscott]

seems most suppliers are currently out of the twist locks/kits but will start searching.

 

[jscott]

in the mean time I wonder if a chain or cable could be used as a safe guard.....Before this Mach 1 my last restoration was a 1960 Nash Metropolitan, see picture. They used a safety chain (also pictured) because the Met had death deifying speeds (almost 50 mph...downhill lol). I wonder if a similar item could be used for a Mustang.

 

[Austin Vert]

I love the idea of making them open honeycombs. I have been planning to do the same thing so I can put an led just inside the honeycomb and make the scoops glow at night. Do you have any pictures of them?

Hi Lazarus,

My apologies for not getting back to you sooner, but i have been super busy chasing other matters in my life.

Glad you dig the drilled out scoop bungs. You asked for pics, so i took a few today, and uploaded them below in my reply. I took shots with different lighting to demonstrate the overall look of them in different day time light and artificial lighting situations. To be honest, you don't really see or notice the bungs much at all as a rule, as they lurk in the shadows of the overhanging scoop eyebrows - sort of out of sight if you will. When you look up closely, you can then see what's going on.

Also, for a bit of fun, you mentioned setting up a kind of backdrop led lighting thing for the scoops. That could be fun. Strictly only visible at night time only, i would think. I would go red leds, as they give the appearance of a fire breathing dragon thing going on.

Speaking of effect lighting, i don't know whether you caught my post on lighting up my running horse grille emblem project. If you didn't, i have included some pics with the horse backlit up. Run it day time or night. It comes on when i turn on my park lights. Easy DIY project. Cool look i think! You could do the horse light up in red , or any colour for that matter. Maybe a colour sequencer for multi coloured effects. Scoop and horse light up could be a funky look!

So all the best regards whatever way you decide to go,

Greg.

 

[SteveO_71]

If you dont want to drill the openings here are billet aluminum ones. Even can get them in different finishes.

https://www.eddiemotorsports.com/product-p/ms275-57.htm

 

[Kilgon]

I would have to question about running with nothing in the opening as I have for the past 2 year and no hood locks. I would think that the air is just passing through and out the cowl area thus not creating that much lift per say. I would also think that any high pressure under the hood would restrict the inflow to some extent also. I can see the locks being more need with an actual plenum since you are building a downward pressure at the air cleaner thus getting a counter reaction of upward push. As mentioned in one of the other posts above it would be great to see a wind test done on ours to see the different effects of with and without. I've been going back and forth about adding ram air to mine. After reading all the discussions about it I went to option 2 for the time being and got the inserts. I drilled and installed them today.

 

[Austin Vert]

I would have to question about running with nothing in the opening as I have for the past 2 year and no hood locks. I would think that the air is just passing through and out the cowl area thus not creating that much lift per say. I would also think that any high pressure under the hood would restrict the inflow to some extent also. I can see the locks being more need with an actual plenum since you are building a downward pressure at the air cleaner thus getting a counter reaction of upward push. As mentioned in one of the other posts above it would be great to see a wind test done on ours to see the different effects of with and without. I've been going back and forth about adding ram air to mine. After reading all the discussions about it I went to option 2 for the time being and got the inserts. I drilled and installed them today.

View attachment 64050View attachment 64051View attachment 64052

Lookin' good there Kilgon! Way to go! Driving around, see if you notice any changes with your temp gauge as i did with mine after drilling out the bungs.

Regards the hood lock thing - i've always seen them as mainly a cosmetic deal, but is a good idea to install them anyway, as a kind of good insurance against anyone's hood blowing open for whatever reason. Always better to be safe than sorry.

Greg.

 

[Lazarus]

Hi Lazarus,

My apologies for not getting back to you sooner, but i have been super busy chasing other matters in my life.

Glad you dig the drilled out scoop bungs. You asked for pics, so i took a few today, and uploaded them below in my reply. I took shots with different lighting to demonstrate the overall look of them in different day time light and artificial lighting situations. To be honest, you don't really see or notice the bungs much at all as a rule, as they lurk in the shadows of the overhanging scoop eyebrows - sort of out of sight if you will. When you look up closely, you can then see what's going on.

Also, for a bit of fun, you mentioned setting up a kind of backdrop led lighting thing for the scoops. That could be fun. Strictly only visible at night time only, i would think. I would go red leds, as they give the appearance of a fire breathing dragon thing going on.

Speaking of effect lighting, i don't know whether you caught my post on lighting up my running horse grille emblem project. If you didn't, i have included some pics with the horse backlit up. Run it day time or night. It comes on when i turn on my park lights. Easy DIY project. Cool look i think! You could do the horse light up in red , or any colour for that matter. Maybe a colour sequencer for multi coloured effects. Scoop and horse light up could be a funky look!

So all the best regards whatever way you decide to go,

Greg.

Thanks very much for the pictures; I really appreciate your taking the time to take and post them. I did see the thread on the glowing coral; well done!

I really like a glowing grille and or emblems and am considering trying something similar. I have been looking at kits made for modern Challengers because they are similar in terms of grille, valence, and hood ducts. I think given the dark colors of my car, I’d like a soft red accent glow. Here are some pics of the Challenger kits I am considering:

 

[Austin Vert]

Thanks very much for the pictures; I really appreciate your taking the time to take and post them. I did see the thread on the glowing coral; well done!

I really like a glowing grille and or emblems and am considering trying something similar. I have been looking at kits made for modern Challengers because they are similar in terms of grille, valence, and hood ducts. I think given the dark colors of my car, I’d like a soft red accent glow. Here are some pics of the Challenger kits I am considering:

Thanks Laz,
Hope you end up with a good result whatever you decide to go with.

Greg.

 

[Blayne9067]

Does it hurt or help if I removed the plastic covers on my 1971 Mach1 hood scopes and replaced with screen mesh?
I tried searching but could not find this question asked before.

I think the car actually looks better with them installed, and for a daily driver without Ram Air it makes sense to have them installed.
I run mine completely open, never had an issue even at speed. I‘m sure the fuel line to carb and carb run cooler with them open, did the temp gun check while troubleshooting fuel gauge pressure indication issue that turned out to be liquid filled gauge.

 

[Kilgon]

Lookin' good there Kilgon! Way to go! Driving around, see if you notice any changes with your temp gauge as i did with mine after drilling out the bungs.

Regards the hood lock thing - i've always seen them as mainly a cosmetic deal, but is a good idea to install them anyway, as a kind of good insurance against anyone's hood blowing open for whatever reason. Always better to be safe than sorry.

Greg.

After doing the install and driving the car several times now I found out that it is running a little warmer with them in and drilled vs not having them in at all. Since I have a holley Sniper installed I'm able to look at the logs I have saved and compare the before and after coolant temperatures. I have also made sure that the outside air temperatures were fairly the same to make sure I was comparing apples to apples. Without inserts engine running average temp of about 180 to 183. With inserts in and drilled I'm running more at the 185 range. I have a 180 thermostat. Never drove it with them blocked all together but I would think it would be a little higher temp yet.