Aftercooler Gains

[Walter Sherwin]

----- Original Message -----
From: "BamaInstrument" <BamaInstrument at email.msn.com>
To: <diy_efi at diy-efi.org>; <gmecm at diy-efi.org>
Sent: Tuesday, April 17, 2001 2:57 PM
Subject: Re: Aftercooler Gains


> I'm not so much interested in high performance in a drag race as having
> consistent high power for years.  I look at the intercooler as a device
> which allows me to run universally available gasoline with a turbo engine.
> So I'm interested.
>
> Q.  Where do you get the 20HP loss?  1 BTU is one pound of water 1 degree
F
> in one Hour and the small auto Air Conditioners produce 5,000 BTU.  That
is
> 83 Lbs of water or about 10 CuFt of water per minute 1 degree F.  I'm
having
> trouble converting that into CFM/degree F/min. But I believe that we have
> about 18,000 CuFt of air at 1 degree C/min or 500 CFM at 36 Degrees F.  So
> if the air is intercooled to, say, 120 degrees F then the AC cooler would
> take it down to 94 degrees F.
>
> There is a good chance that my math is wrong, please help!
>
> dh
>



I agree completely.  Intercooling can well be intended for something much
more than a few seconds of drag racing.  In fact, if your penchant is toward
speed, then such systems must reliably feed/withstand extended periods of
WFO performance.  Every system will vary according to the desired end
result.

I do however like your measure of "years" when in reference to intercooling
sustainability :)

As for the 20Hp loss from the A/C compressor......that was just a SWAG as to
the draw of an OE A/C compressor, on my part, at elevated RPM's.  It is most
likely wrong, and no I did not crunch any numbers to derive it.  I took the
worst benchmark figures that I have heard for such compressors, and
extrapolated so as to imagine the worst higher RPM case.  No science
contained here.  However,  I would suspect significant HP loss at high RPM,
if the compressor was not defeated.

By the way, does anyone have any real AC compressor figures to examine, at a
variety of full load shaft speeds?

Your math is probably correct, don't rely upon mine at this point.

Since you appear well adept with thermo crunching, what do you specifically
think of the air/dynalene/freon hybrid intercooling system found at
www.coolflow.com?  Would be very interested in hearing your thoughts.


Thanks;
Walt.

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org