Driving Without A Thermostat

On Mon, 14 Feb 2005, Mike Romain wrote:

> We do silly things like add or change fans and shrouds, but we sure as
> hell 'don't' take the thermostats out or even sillier run something like
> a 160 t-stat thinking it is going to 'cool' them down. LOL!

Good. Both of those are dumb ideas.

"Mike Romain" > wrote in message
...
> "Daniel J. Stern" wrote:
> >
> > On Mon, 14 Feb 2005, Mike Romain wrote:
> >
> > > Have either of you ever seen a race set up V8 or are you just another
> > > internet BS'er?
> >
> > Riiiiiight, Mike. All wisdom and knowledge will die with you. Nice try,
> > though. We're talking about street-driven vehicles, not racecars.
>
> There are a lot of us that use our daily drivers for serious high rpm
> and high load applications or run weekend warriors that do the same.
>
> The OP was talking about a big ford V8 in a truck wasn't he?
>
> I can tell you I along with a 'whole' bunch of folks I know run our
> Jeeps hard enough that we have to stop and let them cool off on a
> regular basis.
>
> We do silly things like add or change fans and shrouds, but we sure as
> hell 'don't' take the thermostats out or even sillier run something like
> a 160 t-stat thinking it is going to 'cool' them down. LOL!
>
> There is a reason the flow has to be balanced in an engine which is the
> reason they sell the restrictors for race engines and even more so the
> reason they use the things.

it's pointless to try and explain it to the > know-it-alls <!!!
let them think they know it all -- but we BOTH know better <G>
BBA

Mike Romain wrote:
>
> The fluid has to have time to transfer the heat for one and for 2 the
> fluid can make air bubbles if moving too fast which makes hot spots in
> an engine.
>

ok, so can someone answer me this:

why don't y'all just run a bigger water pump pulley to slow the flow
down at high rpm if it's flowing too fast instead of restrictors? Or
maybe just kink the upper rad hose?

I ran my Enduro car last year with a 160 Tstat and without anything...
and in both cases it ran about 210-220 degrees assuming I didn't punch a
hole in the rad (when it ran 260...)

For me, the two biggest things for improvement was a proper fan shroud
and building ductwork/airdam for in front of the rad to keep the air
moving through. The last race (ok, it was cooler) I didn't even crack
200 and I was using the small rad because I had damaged the big rad.
(160 Tstat.)

200 Lap dirt track racing btw... lots of overheating.

I have a theory that this is one of those "one size doesn't fit all"
rules... the tstat determines how cool the engine will run, not how hot
it will run... but "tampering" with the flow (by removing the tstat) in
some engines seems to cause grief as well by upsetting the "balance..."

I'd like to see some dyno runs comparing water temp...

Ray

ray wrote:
>
> Mike Romain wrote:
> >
> > The fluid has to have time to transfer the heat for one and for 2 the
> > fluid can make air bubbles if moving too fast which makes hot spots in
> > an engine.
> >
>
> ok, so can someone answer me this:
>
> why don't y'all just run a bigger water pump pulley to slow the flow
> down at high rpm if it's flowing too fast instead of restrictors? Or
> maybe just kink the upper rad hose?
>
> I ran my Enduro car last year with a 160 Tstat and without anything...
> and in both cases it ran about 210-220 degrees assuming I didn't punch a
> hole in the rad (when it ran 260...)
>
> For me, the two biggest things for improvement was a proper fan shroud
> and building ductwork/airdam for in front of the rad to keep the air
> moving through. The last race (ok, it was cooler) I didn't even crack
> 200 and I was using the small rad because I had damaged the big rad.
> (160 Tstat.)
>
> 200 Lap dirt track racing btw... lots of overheating.
>
> I have a theory that this is one of those "one size doesn't fit all"
> rules... the tstat determines how cool the engine will run, not how hot
> it will run... but "tampering" with the flow (by removing the tstat) in
> some engines seems to cause grief as well by upsetting the "balance..."
>
> I'd like to see some dyno runs comparing water temp...
>
> Ray

The only reason really to 'not' run a t-stat is it is one less part that
can break at the wrong time. A 'hole' never breaks....

A proper t-stat no matter the temp has the correct flow rate for the
size of the holes and channels. Thermostats only regulate how 'cold'
the engine runs, how hot it runs is up to the rest of the system.

I used to race a Mini with a 1275 CC Cooper engine on a dirt and snow
track and she ran hot at full throttle. Even it overheated with no
thermostat....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

I get the feeling that a lot of people are right on this one - except
perhaps the guy who doesn't run a thermostat because he likes his engine to
run as cool as possible.

In my street cars, I run a 180 - 190 degree thermostat - or whatever came in
the car stock.

In my race cars I do a number of things - in order of preference:

No thermostat, but a flow restrictor selected by experimentation to keep the
flow in the head right. Different for every type of motor. My BMW M10
motor appears to not need a restrictor.

Reduce the water pump speed to 50% - 70% of crank speed with a bigger
pulley. This works as a rule of thumb, the idea is the slowest speed that
still keeps the engine cool. Benefit is reduced power to run the pump.
Sometimes the pump won't keep the engine cool at idle. Side benefit is
reduced cavitation at high RPM.

Control the amount of cooling by taping the rad or blocking off the rad
inlet.

As a last resort, run a thermostat. Big benefit: you can force the engine
to warm up to at least the temp of the thermostat. Big drawback - they have
failed in such a way as to stick closed. Guaranteed overheat when that
happens. I had one engine/car combination that I had to run a thermostat
in, even taping the rad right off wouldn't warm this thing up. It never
failed, either. I always made a point of watching for it to operate,
though, you could tell by the temp gauge exactly when it opened.

I always look for at least 180 degrees of water temp as a minimum. The big
advantage of the thermostat method is that you can basically force the
engine up to that point. The drawback of the tape method is that you can't
adjust it readily - you have to manually change the tape. An advantage is
that you can reduce drag this way by letting less air into the rad, or you
can reduce weight by running smaller rads - even harder to adjust, you need
to install another rad!

Brian


"ray" > wrote in message
...
> Mike Romain wrote:
>>
>> The fluid has to have time to transfer the heat for one and for 2 the
>> fluid can make air bubbles if moving too fast which makes hot spots in
>> an engine.
>>
>
> ok, so can someone answer me this:
>
> why don't y'all just run a bigger water pump pulley to slow the flow down
> at high rpm if it's flowing too fast instead of restrictors? Or maybe
> just kink the upper rad hose?
>
> I ran my Enduro car last year with a 160 Tstat and without anything... and
> in both cases it ran about 210-220 degrees assuming I didn't punch a hole
> in the rad (when it ran 260...)
>
> For me, the two biggest things for improvement was a proper fan shroud and
> building ductwork/airdam for in front of the rad to keep the air moving
> through. The last race (ok, it was cooler) I didn't even crack 200 and I
> was using the small rad because I had damaged the big rad. (160 Tstat.)
>
> 200 Lap dirt track racing btw... lots of overheating.
>
> I have a theory that this is one of those "one size doesn't fit all"
> rules... the tstat determines how cool the engine will run, not how hot it
> will run... but "tampering" with the flow (by removing the tstat) in some
> engines seems to cause grief as well by upsetting the "balance..."
>
> I'd like to see some dyno runs comparing water temp...
>
> Ray

Once upon a time in the early '60's, most passenger vehicles used a low-pressure
type of a radiator cap. So, @ a higher RPM, the water pump pressure would
overcome the radiator cap's rating and force coolant out, resulting in an
overheated engine. Many of us believed that these situations were caused because
the coolant was flowing through the radiator so fast, that the coolant mixture
did not have time to cool!!!! Using restrictors prevented the coolant from
being forced out the cap, and allowed the engine to run cooler. However,
passenger vehicles built in the past 30 or so years use a different type system,
A cross flow radiator!!! The cap is @ the low-pressure side of the (radiator)
cooling system. No more water pump pressure issues! Now the system actually
will work more effectively with more volumes of water!!!!



Misconceptions:

to decrease ones thermostat temp rating = lower engine operating temp. = If the
cooling system can't keep up with the heat the engine is generating, a cooler
thermostat may help!!!



Another: if the engine cooling is working good, more must be better!!!



one mo if coolant flows too quickly through the system, then it will not have
time to cool the engine properly. -- most gas engine cooling systems are a
CLOSED LOOP System!!

--
BBA
°?°
BBA's RC Site - http://www.billybadassrc.com
When Privacy Matters -- http://www.epic.org

On Mon, 14 Feb 2005, Billy Bad Assr=A9 wrote:

> Once upon a time in the early '60's, most passenger vehicles used a
> low-pressure type of a radiator cap.

Early '50s, yes. Early '60s, no. By the early '60s, 14psi to 16psi caps
were the most common.

> So, @ a higher RPM, the water pump pressure would
> overcome the radiator cap's rating and force coolant out

Bzzt! There is no "water pump pressure". The water pump does not generate
pressure. Pressure in the cooling system is created by thermally-induced
expansion.

> Many of us believed that these situations were caused because the
> coolant was flowing through the radiator so fast, that the coolant
> mixture did not have time to cool!

Many ignorant people believe lots of stupid things.

> However, passenger vehicles built in the past 30 or so years use a
> different type system, A cross flow radiator!!! The cap is @ the
> low-pressure side of the (radiator) cooling system. No more water pump
> pressure issues! Now the system actually will work more effectively with
> more volumes of water!!!!

Goodness, you're ignorant. The flow orientation of the radiator does not
constitute a "different system". The cap is not at the "low pressure side"
of the radiator/cooling system because there is no "low pressure side".
All parts of the cooling system are at equal pressure at all times. There
are no "water pump pressure issues" because there is no "water pump
pressure". The flow orientation of the radiator does not directly affect
the volume of the system.

> Misconceptions:

Yes, lots of them. Mostly in your head.

"Daniel J. Stern" > wrote in message
n.umich.edu...
On Mon, 14 Feb 2005, Billy Bad Assr wrote:

> Once upon a time in the early '60's, most passenger vehicles used a
> low-pressure type of a radiator cap.

Early '50s, yes. Early '60s, no. By the early '60s, 14psi to 16psi caps
were the most common.

> So, @ a higher RPM, the water pump pressure would
> overcome the radiator cap's rating and force coolant out

Bzzt! There is no "water pump pressure". The water pump does not generate
pressure. Pressure in the cooling system is created by thermally-induced
expansion.

Bah >> pressure, meaning the Flowing side!!!! if I increase the rpms -- what do
you suppose the water pump will do???!
the Flow will be increased!

> Many of us believed that these situations were caused because the
> coolant was flowing through the radiator so fast, that the coolant
> mixture did not have time to cool!

Many ignorant people believe lots of stupid things.

> However, passenger vehicles built in the past 30 or so years use a
> different type system, A cross flow radiator!!! The cap is @ the
> low-pressure side of the (radiator) cooling system. No more water pump
> pressure issues! Now the system actually will work more effectively with
> more volumes of water!!!!

Goodness, you're ignorant. The flow orientation of the radiator does not
constitute a "different system". The cap is not at the "low pressure side"

Okay, fine -- instead of the term "low Pressure Side" use "SUCTION SIDE"!!!

of the radiator/cooling system because there is no "low pressure side".
All parts of the cooling system are at equal pressure at all times. There
are no "water pump pressure issues" because there is no "water pump
pressure". The flow orientation of the radiator does not directly affect
the volume of the system.


BBA
°?°
RMRL FAQ -- http://www.faqs.org/faqs/models/rc-cars/newbie-guide/
BBA's RC Site - http://www.billybadassrc.com
When Privacy Matters -- http://www.epic.org

"Billy Bad Assr©" > wrote in message
...
> Once upon a time in the early '60's, most passenger vehicles used a
low-pressure
> type of a radiator cap. So, @ a higher RPM, the water pump pressure
would
> overcome the radiator cap's rating and force coolant out, resulting in
an
> overheated engine. Many of us believed that these situations were
caused because
> the coolant was flowing through the radiator so fast, that the coolant
mixture
> did not have time to cool!!!! Using restrictors prevented the coolant
from
> being forced out the cap, and allowed the engine to run cooler.
However,
> passenger vehicles built in the past 30 or so years use a different
type system,
> A cross flow radiator!!! The cap is @ the low-pressure side of the
(radiator)
> cooling system. No more water pump pressure issues! Now the system
actually
> will work more effectively with more volumes of water!!!!
>
>
>
> Misconceptions:
>
> to decrease ones thermostat temp rating = lower engine operating temp.
= If the
> cooling system can't keep up with the heat the engine is generating, a
cooler
> thermostat may help!!!
>
>
>
> Another: if the engine cooling is working good, more must be better!!!
>
>
>
> one mo if coolant flows too quickly through the system, then it
will not have
> time to cool the engine properly. -- most gas engine cooling systems
are a
> CLOSED LOOP System!!
>
> --
> BBA
> °?°
> BBA's RC Site - http://www.billybadassrc.com
> When Privacy Matters -- http://www.epic.org
>
>

As incompetent a post as this reader has ever encountered.

> As incompetent a post as this reader has ever encountered.

Huh -- what are you implying?