View Single Post
  #7 (permalink)  
Old 08-06-2002, 06:57 PM
Naja's Avatar
Naja Naja is offline
CC Member
Visit my Photo Gallery

 
Join Date: Jul 2000
Location: Deer Park, TX, USA,
Posts: 128
Not Ranked     
Default

Thanx for your comments, guys -

I've had a variety of problems (including exhaust gases in the coolant), but I think I am at the point of 'fine tuning' now. To make cooling as efficient as practical, I'm pursuing a couple of things, such as the water pump speed.

A guy just sent me the pulley sizes from a late '70s 460, and the water pump is 25% overdriven. He will be sending me an early '70s 460 measurements in a couple of days for comparison.

I anticipate that most of my driving will be between 40-55 mph (1500-2000 rpm). That means that at 40 mph (with my current 8% underdrive pulley), the pump is turning about the same speed as at idle with a 9% overdrive pulley, and airflow through the radiator may not be significant. I figure that if most of my driving will be at these rpm's, I might as well configure the water pump pulley to give the coolant flow that the engine was designed for - apparently requiring something akin to 20-30% overdrive. Sure, if I do a lot of racing, or want to run around at 3-4000 rpm (making a racket and wasting gas) constantly, an underdrive pulley makes sense.

I've got a heavy Cobra (perfect for the touring that I intend to do), a C6, and a/c (that I have'nt been using, yet), an .080 overbored engine, and the temp around Houston is over 90 for much of the year, meaning that I have the potential for very high heat loading of the coolant system. Therefore, I want to get as much out of my 7 core radiator, 16 lb. cap, and 2800 cfm Flex-A-Lite fan as possible. That means optimizing other system components. (I've also moved my trans cooler to the rear with its own fan - both fans are switchable). I am just now plugging the holes in the shroud I built to direct all of the air that enters the front through the radiator, rather than having a significant portion going around by the tires. I am also going to investigate the effect of opening the hood slightly. If it makes a significant difference, I'll look into ways to allow hot air to escape with it closed - louvers in the hood, ? ? ?, etc.

Like I say, I think I am OK at this point, but I would rather tweek a few things to give myself a cushion, than to be running 'at the edge'.

Any other ideas will be appreciated.

Regards,
Frank
Reply With Quote