But not if it's sealed to the air cleaner! In this case the duct and
scoop are completely independent of the radiator airflow and ambient air,
and have no effect on them whatsoever. In other words, the addition of a
scoop and sealed duct makes no difference to anything else in the engine
compartment. Cooling airflow remains exactly as before. Ambient pressure
remains exactly as before. Carburetor intake air pressure presumably
increases, but that's neither here nor there.
Barrie Robinson had this to say:
>The flow of air through the rad is the most benificial. The flow is best
>when the "end" of the air run is at a low pressure. The higher the
>difference between rad entry and engine bay exit the better. The scoop
>will ram air into the "end" of the air "tube" thus increasing pressure and
>adversley affecting the flow of air through the rad - I think!
>
>At 04:59 PM 7/12/00 -0700, Max Heim wrote:
>>Interesting points, but...
>>
>>I assumed James was indeed going to duct the air from the scoop to the
>>air cleaner. But I do not understand why you think this will raise
>>underhood temperatures, since in a stock hood there is no scoop at all,
>>so all the ambient air flowing into the engine compartment is coming from
>>somewhere else anyway. His modification will have no effect on this air
>>source whatsoever. So as far as I can see all this concern about the
>>electronics overheating (or anything overheating) is completely
>>unwarranted. Perhaps you are thinking of a situation with a full
>>bellypan, or where all the holes in the radiator diaphragm are sealed.
>>
>>Michael Singleton had this to say:
>>
>>>Keep in mind that with your new ram air hood, most of the benefit will be
>>>largely cosmetic, unless you take a lot of time with ducting to the carb(s)
>>>and sealing the air flow within the ducts. Further, all of this ducting will
>>>raise the underhood temps, if it is done correctly, as the ducting will seal
>>>off much of the cool ambient air flowing into the engine compartment,
>>>leaving only air from through the radiator. Another consideration is to make
>>>sure that the distributer, if it is like a Chevy unit - on top or the
>>>engine, remains cool enough so that any electronics in the distributer body
>>>don't get cooked. This became a major problem on one racer I was involved
>>>with - The combination of radical sealing of the intake air flow, engine
>>>heat, and an electronic ignition didn't work. So if you are using a
>>>non-mechanical distributer, consider getting some cooling air to it. Your
>>>street car will probably have higher underhood temps, because it is standing
>>>still, or at low speeds more than a race car at track speeds at Riverside.
>>
>>
>>--
>>
>>Max Heim
>>'66 MGB GHN3L76149
>>If you're near Mountain View, CA,
>>it's the red one with the silver bootlid.
>>
>>
>
>
>Regards
>Barrie Robinson
>barrier@bconnex.net
>
>
>
--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the red one with the silver bootlid.
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