Geeez, now all I need for my electric pump is a 50 psi radiator cap. And
Keith thought his radiator was poofed with a 22 lb. cap.
Actually Brian what you saying does makes sense.
JB
----- Original Message -----
From: "Bryan A. Savage Jr" <basavage@earthlink.net>
To: "dahlgren" <dahlgren@uconect.net>
Cc: <ardunbill@webtv.net>; <land-speed@autox.team.net>
Sent: Saturday, October 07, 2000 5:11 PM
Subject: Re: Cooling
> Hello all...
> Dave's point is very important when you start to push the envelope.
> The only place pressure is needed is at hot spots.
> You can get it by having a low volume pump (20), in an unrestricted
> sealed system pressurized to 40-50 PSI.
> Or you can have an unrestricted system with a 200 GPM pump and restrict
> the engine outlet to produce the same 40-50 PSI at the hot spots.
> Or a combo of the two.
> Like using washers to restrict the flow in a flat head with a 7 PSI
> pressure cap.
> But until you start having a problem with detonation, which is usually
> the first sign of this problem, it's just something to be aware of.
>
> Bryan Savage
>
> dahlgren wrote:
> >
> > The point that is missed here is the need for a pressure system and the
> > more pressure the better. 22 lbs is pretty common. It is not so much to
> > raise the boiling point which it does help but to eliminate small air
> > pockets that cause localized steam and high temp areas.. I have worked
> > on some engines that raised the pressure to 30 psi before even starting
> > the engine..some of these ran at 50 psi under a load.
> > Dave Dahlgren
> >
> > ardunbill@webtv.net wrote:
> > >
> > > Hi Folks. Read the items about cooling with interest. I have a 15
gpm
> > > Jabsco 12V marine coolant circulating pump which they tell me is
> > > in widespread use for cooling converted auto engines in marine use
where
> > > sea water is not used, but there is some form of heat exchanger so tap
> > > water and antifreeze mix is used in the engine as per car practice.
> > >
> > > I certainly question the idea that a huge gpm figure is necessary for
> > > speed trials engine cooling. You're only running a short while, even
at
> > > Bonneville, so the practice for decades has been, has it not, electric
> > > pumps like mine, and vented systems, so you just run down there, and
> > > heat your 10 to 20 or more gallons of water up gradually so that the
> > > run's over before boiling point is reached.
> > >
> > > I do agree that a thermostat makes complete sense, you get your engine
> > > hot enough to "go", but your cooling water is not hot, so you have
more
> > > running time than if you heat the whole system up to some point.
> > >
> > > I think the expert Keith cited is right that the engine makes best
power
> > > a little over 200, evidence for it is that the Japanese water-cooled
> > > motorcycles commonly use thermostats about 205 degrees. With 50/50
> > > antifreeze you have a boiling point way up there, 226 with no
pressure,
> > > and higher with pressure. So no practical reason why you can't run
205
> > > with a speed trials iron.
> > >
> > > My Ardun worked fine with the 15 gpm pump, 180 degree thermostats, and
> > > 10 gallons in the system with a trunk-mounted tank, at Maxton last
> > > weekend. This may be a different matter than a SB Chevy with
tremendous
> > > power output and smallish aluminum heads. The Ardun aluminum heads
> > > weigh maybe 50 pounds apiece and are thought to have a lot of
> > > AIR-cooling value from their sheer size. The bottom line is, a
working
> > > system that gives you the endurance and running temperature you want.
> > > Cheers from ArdunBill in the Great Dismal Swamp, Chesapeake, VA
> > >
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