Rad intake air deflector plates

[Hoghead]

Looking at reasons why I run hot at idle and notice that the air deflector plates in front of the radiator do not touch the rad housing vertical sides but end about 20mm short
Is this correct as it seems that they should reach back as far as the rad?

Any other deflector or blocking plates that can be added to improve airflow?

I see an under car air dam - does this improve airflow at idle or just on the move?

 

[Keoke]

Nope:
The radiator in a Healey has virtually been encased in baffels by others, with little thermal improvement.

Our road cars seem to respond best to recored copper radiators utilizing more cores and serpentine cooling fins along with a Texas ciiler Fan.

 

[Randy Forbes]

Nope:
The radiator in a Healey has virtually been encased in baffels by others, with little thermal improvement.

Our road cars seem to respond best to recored copper radiators utilizing more cores and serpentine cooling fins along with a Texas ciiler Fan.

What he said!

I had a new core fitted, at the time it was referred to as a "competition TX core" back in 1979 or 80, and it held close to 1-1/2 MORE gallons than stock. I once compared it to a known original core on a MKIII, and it was TWICE as thick.

Obviously, if all you had was more water, it would only delay the same overheating condition, but giving the same water more surface to air area increases the amount of heat transfer. On a 90*+ day here in SW Florida, my car runs about 180* (on the gauge...) so I'm happy. I did however fit a thermostatically controlled Kenlowe fan some years back, while still living in Ohio, so I'm sure that contributes too (as well as some homemade stainless steel baffles to direct air into the radiator...).

 

[RAC68]

The air directors in front of the radiator do not touch or even come that close to the radiator. They were meant to direct the air stream from outside at speed.

However, the main issue of why you run hot at idle is primarily a multi faceted condition. First, if you are using an aggressive fan, there is no directed passage out of the engine compartment that allows full and easy flow. This hot air finds its easiest path (with the car stopped) through the porous radiator bulkhead (especially around the steering box). To make matters worse, this escaping hot engine compartment air is then reintroduced through the radiator by the drag of the fan. This recursive passage of heated air continuously increases in temperature, thereby giving less and less relief to the engine. Add to this condition, the lack of effective fan air control that, as original, has no shroud to stop air from leaking of the tips of the fan blades and you have a very inefficient engine cooling system. Attempts by many of us to compensate this misunderstood condition by introducing very aggressive fans, larger radiators, and even fender vents and louvers and the resulting effect is much less than expected or desired.

Although the best thing to do could be to create a non-porous radiator bulkhead that forces air to pass through the radiator when entering the engine compartment and venting far from its point of entry. However, this would not be practical or simple to achieve on a completed car as it would require disassembly and fabrication. In addition, discussions in other threads show the difficulty of coming to a decision of how far to go with the introduction of changes that may better the situation but loose the character of the car we chose to have in the first place.

Although I have come to the belief that the main factor causing the issue you are questioning is the presence of a porous radiator bulkhead, the way to provide some compensation is with the installation of a more efficient radiator and more aggressive fan with simple fan shroud. Going further would require major effort based only upon theoretical validation.

By the way, if you are not using a "Sleeved" thermostat that blocks the internal radiator bypass for quick warm-ups, you are also loosing 20% of your cooling by providing an in-engine radiator bypass.

Do the easy things. Make sure you have a sleeved thermostat, good fan with simple shroud, more efficient radiator (if needed) and enjoy your Healey drives during the cool part of the day while listening to the “Beach Boys”.

Sorry for going off like I did.
All the best,
Ray (64BJ8P1)

 

[steveg]

...
The radiator in a Healey has virtually been encased in baffels by others, with little thermal improvement.

Not true, Keoke:
The others who have done this have noticed actual improvement and do not appreciate having their work disparaged by those who have no experience with it.

 

[Hoghead]

I have a shroud that completely encircles the fan and a multi blade plast ic fan. Not sure if it is a Texas cooler or not as the blades are symetrical
Thermostat is the sleeved tyle

 

[Keoke]

The others who have done this have noticed actual improvement and do not appreciate having their work disparaged by those who have no experience with it.
OH!! Sorry:

I was born yesterday.