Louvers

[pan]

Rick, I have to say that in my opinion louvres look a bit out of place on six cylinder Healeys. With the bonnet scoop already there rows of louvres make the bonnet look a bit crowded. The Works Rally cars had exit vents at the rear of the bonnet which look better to me, and are probably more effective.

 

[RAC68]

Rick,

I totally agree and appreciate your suggestions. The primary issue I plan to address when it gets warmer in NJ is engine compartment air flow and that starts with eliminating hot radiator air recirculation. Once that is completed, air extraction from the engine compartment will need to be addressed or flow will slow dramatically and the benefits of the first task will be diminished or even eliminated.

Until the completion of the first part of the project, I will not know to what extent the louvers will need to contribute in the second or if fender vents or PAM's Works exit vents (which I wasn't aware of) should be considered.

Thanks again,
Ray(64BJ8P1)

 

[HealeyRick]

Rick, I have to say that in my opinion louvres look a bit out of place on six cylinder Healeys. With the bonnet scoop already there rows of louvres make the bonnet look a bit crowded. The Works Rally cars had exit vents at the rear of the bonnet which look better to me, and are probably more effective.

Alwyn,

I understand your point of view. Obviously, I like the look but maybe that's just because I like louvers and needed a place to put them. I didn't recall seeing the exit vents on the Rally cars before and found this photo of URX 727. It's quite a nice design and one Ray might take a look at:

 

[elrey]

Underneath the fender spear on my BT7 there are two small holes that seem to be vent holes since the spear has a small notch on it's underside. Granted, these holes are small and would seem to be ineffective as vents. Are they vents, are they just there for grins, or what?

 

[RAC68]

Rick,

The picture reflects the type of assumed function I will be looking to satisfy.

Thanks for the picture. It is definitely food for thought,

Ray(64BJ8P1)

 

[John Turney]

Thanks for that photo of URX 727. That was the early attempt to exhaust heat from the engine compartment. It didn't work that well because of the high pressure area in front of the windscreen. That's why they went to the side vents.

 

[roscoe]

Well, it's done, at least until I decide to strip and reshoot the paint with just a touch of lampblack tint added to the color. The lighter color became a little more obvious in the light of day. I can live with it. I'm not even sure the color is an exact match in terms of tints because of course after 7 years they no longer call it mineral grey...it is now called titanium. I'll prolbably live with it. It's either that or scold the guy who shot it, although I never get anywhere talking to myself.
Rather than buy the reproduction brackets that are out there, I made these from .125" aluminum sheet by folding 3 edges around a form and finishing them through buffing. Thank you all again for the help.

 

[aero3113]

Great work!!

 

[RAC68]

John,

Its nice to know what they discovered before we again spend time and effort to come to the same conclusion. This is what happened when I promoted the installation of a bilge blower in the cold air duct and rediscovered hot radiator air recirculation. If I had known what Healey had found back in the late 50s, I would not have been surprised by hot air being sucked into the cold air duct after installing a blower.

Well, I will drop back and address the hot air recirculation and cold air duct pickup issues and wait till I know what I need before I investigate approaches for air flow and evacuation from the engine compartment.

Again, thank you John,
Ray(64BJ8P1)

Jon,

Your work looks great. When I remember how bad a number of panels were so misaligned when my New Healey was delivered, your work is definitely on a higher quality plane. Although I was quite enthusiastic when receiving my New Healey, it took me a few months to develop the nerve to refit fenders and doors on this new car to an acceptable alignment. So, from my perspective, you have bettered Healey manufacturing.
Great Job JON

Ray(64BJ8P1)

 

[HealeyRick]

The problem with trying to make louvers so that they are effective in reducing underhood temps is that we don't really have any empirical data. We are, in effect and with all due apologies, "whistling in the wind." I found this great picture on Barney Gaylord's MGA site and while it's probably not directly applicable to the Healey because of different grill openings in the front shroud, it still remains of interest:

Note the high-pressure area in front of the windscreen that actually is blowing air backwards and explains those cowl-induction hoods that were so popular on Chevy muscle cars. You can read the results of the MGA wind tests here: https://mgaguru.com/mgtech/history/hs130.htm

We often talk about fender vents on Healeys but MGA Twincams had different kinds of fender vents ... inner fender vents. The fenderwells are low-pressure areas and the idea is air from the high-pressure area inside the engine compartment will flow to the low-pressure area. I'm surprised that we haven't seen anyone try this on a Healey as it would be fairly easy to do without the exterior bodywork necessary for the Works style vents. The MGA panels are actually available from Kilmartin:

Here's some more info on them: https://mgaguru.com/mgtech/twincam/tc117.htm

 

[RAC68]

Rick,

Placement, Placement, Placement....that is the question. A vent or louver is not difficult to make (in concept) but finding where to place it to achieve the desired objective is. Without specialty equipment able to help identify where the vent is most effectively placed, you are left with perception, logic, the discoveries of others, and guesses and easily cause the vent to be placed in a non-contributing, if not counter acting position. John's fan shroud work is a great example of being surprised when discovering the real result of initial fan effectiveness in his work.

Thanks Rick, it is definitely food for thought.
Ray(64BJ8P1)

 

[HealeyRick]

Rick,

Placement, Placement, Placement....that is the question. A vent or louver is not difficult to make (in concept) but finding where to place it to achieve the desired objective is. Without specialty equipment able to help identify where the vent is most effectively placed, you are left with perception, logic, the discoveries of others, and guesses and easily cause the vent to be placed in a non-contributing, if not counter acting position. John's fan shroud work is a great example of being surprised when discovering the real result of initial fan effectiveness in his work.

Thanks Rick, it is definitely food for thought.
Ray(64BJ8P1)

Ray.

I think you need to lay in a supply of yarn strips and start doing some testing.

 

[RAC68]

Ray. I think you need to lay in a supply of yarn strips and start doing some testing. ​

​

Rick,

Maybe so. If it doesn't work out I can always sew up a cozy for my shifter.

Looking forward to meeting one day,
Ray(64BJ8P1)

 

[HealeyRick]

Rick,



Looking forward to meeting one day,
Ray(64BJ8P1)

That would be great and I have a perfect opportunity. Come on up to our Healey Seaside Summit in August: https://www.ahca-newengland.org/summit-2018.html Should be a few AHSTC guys coming up you can caravan with.

 

[steveg]

Re the MGA louvers - the thing is whether the fender wells are low-pressure or high-pressure areas. We have great big openings around the suspension and our question is - is that just another way for hot air to go forward and be recirculated through the radiator?

I'm having good results having blocked these openings and also the other paths for hot air to be recirculated forward.

 

[HealeyRick]

Steve,

My BJ7 had been an SCCA racer last used in the '60s when I bought it and had aluminum panels very similar to yours around the shock absorbers.

 

[John Turney]

The problem with trying to make louvers so that they are effective in reducing underhood temps is that we don't really have any empirical data. We are, in effect and with all due apologies, "whistling in the wind." I found this great picture on Barney Gaylord's MGA site and while it's probably not directly applicable to the Healey because of different grill openings in the front shroud, it still remains of interest:

View attachment 52310

Note the high-pressure area in front of the windscreen that actually is blowing air backwards and explains those cowl-induction hoods that were so popular on Chevy muscle cars. You can read the results of the MGA wind tests here: https://mgaguru.com/mgtech/history/hs130.htm

...

Excellent summary article on airflow testing. thanks for that!!

Not only does it confirm the high pressure area in front of the windscreen, but air flows downward into those shroud vents on the MGA. On the other hand, a low-pressure area forms under the car, extracting engine compartment air.

 

[John Turney]

The link to this "10 Classic Ads from the JC Whitney Catalog" was in the Pub. Scroll down to the last ad for the louver punch. https://bestride.com/news/entertainment/10-classic-ads-from-the-jc-whitney-catalog

 

[roscoe]

$6.95..... I wonder what paint cost back then. The paint was far and away the most expensive part of my louver job. If they had a 5" version I would have looked up my old pals Mr. Peabody and his boy Sherman to borrow their "way-back" machine and picked one of those beauties up. Come to think of it, until I moved the last time I probably had that JC Whitney catalog issue.

 

[Duane_Rhynard]

The link to this "10 Classic Ads from the JC Whitney Catalog" was in the Pub. Scroll down to the last ad for the louver punch. https://bestride.com/news/entertainment/10-classic-ads-from-the-jc-whitney-catalog

The advice at the bottom is hilarious!