[DeTomaso] Radiator Dilemma

[MikeLDrew at aol.com]

Hey all - I need some good advice on radiators. I currently have a Fluidyne 
performance unit without a shroud. I've been told that a shroud is a 
necessity, which I understand. 

>>>Not to put too fine a point on it, but that is not strictly true.

It all depends on the configuration of your radiator currently.   Do you 
have it in the stock position, with pusher fans?   If so, the car came from 
the factory with two side pieces and a top cover, which helped ensure all air 
flowing through the grille would be forced through the radiator and not 
spill around the sides.   If you don't have those, you definitely owe it to 
yourself to get them.

Do you have your radiator tilted forward, with sucker fans?   If so, it's 
still important to shroud the sides and top as much as possible.

Aftermarket sucker fans are pretty powerful, and while there is perhaps 
something to be gained by fitting the back side of the radiator with an 
all-encompassing shroud, there is also something to be lost, as at high speeds the 
air can stagnate because it can't escape quickly enough due to the blockage 
formed by the shroud.

Johnny Woods uses Flex-A-Lite sucker fans with integral shroud on his car, 
and he experienced high-speed overheating that he attributed to this 
problem.   He cut holes in the shroud and fitted hinged flaps that blow up when the 
pressure behind the radiator becomes excessive, and that fixed his problem 
completely.

>I've had it for about 12 years now - no leaks.

>>>Be very happy.   They have been known to leak, especially the early 
ones.   Sometimes the radiator is so large that it physically touches the body, 
and when the body flexes it bends the radiator and causes it to leak.   As 
long as it is properly mounted, with rubber isolation both at the bottom and 
the sides, it should be fine.

So if you have a radiator that isn't leaking, why are you talking about 
changing it?   The Fluidyne radiator is more than you need, as long as the 
system is properly bled and the fans are working etc.

So what exactly are we talking about here?

 >The rumblings on The List lean towards a unit by Dennis Quella(?) - don't 
know the correct spelling or the company, but the last I had read from 
someone was just to get his radiator and “be done with it”. 

>>>That was, I thought, a laughable suggestion to spend $2000 to fix a $200 
problem, of a perfectly good radiator that had sprung a leak and just 
needed to be repaired (which it subsequently was).

>I think it was a double-pass (I guess that's good) - and I assume it's 
shrouded. 

>>>The DQ radiator made by Ron Dennis is fantastic, no doubt.

>Another side of me asks - which is better - copper or aluminum? And Why?

>>>Aluminum's chief advantage is that it is lighter.   However, the 
disadvantage is (supposedly) that it doesn't shed heat as well, so for equal 
heat-shedding performance, an aluminum radiator needs to be made larger, which 
means it holds more water, which means you gain back much of the weight you 
supposedly saved once it's in the car.

The chief disadvantage of aluminum is that they are normally not 
repairable.   The discussion last week centered around a high-quality brass Hall 
radiator that had sprung a leak; a crooked shop quoted $600 to repair it which is 
as much as it costs to replace it.   He took it to an honest shop and they 
totally restored it for $250.

When you are driving down the road and your radiator springs a leak far 
from home, you can normally get a brass radiator repaired locally without much 
trouble.   When an aluminum radiator picks up a rock and springs a leak, you 
take it out and throw it away. :<(

> I know the copper units are heavier, but I am not concerned about extra 
weight. I am familiar with the company   - Brassworks - they have been at it 
since the early 1900's. Ken and Lela MacArthur had mentioned Brassworks in 
July. So - here we go - I know the discussion will generate a fair amount of 
opinions - which I always welcome, since it will generate more questions 
too. Looking forward to hearing from all the experts - i know you are out 
there.

>>>You will likely get differing opinions, and that's fine.

However, I would say that you are talking about replacing your radiator 
without first identifying exactly WHY you are talking about replacing it?   If 
your Fluidyne was leaking, that would be an automatic response.   But if 
it's not leaking, what is your issue?   

Overheating at slow speeds but cools fine when going down the road?   
That's either poor fan performance, wrong thermostat (Windsor instead of 
Cleveland), or air in the system.

Overheating all the time, even when going down the road?   Almost assuredly 
air in the system.

Neither condition requires a radiator change.   If you had a stock, 
original radiator that was visibly leaking and whose fins had separated from the 
core, for sure you would want to replace it.   As it is, IF you even have a 
problem, it's a maintenance issue.   In fact, changing the radiator is likely 
to make the problem worse, not better, if when you refill it you don't bleed 
it properly.

So please, tell us exactly what is prompting this discussion.

Cheers!

Mike
-------------- next part --------------
   Hey all - I need some good advice on radiators. I currently have a
   Fluidyne performance unit without a shroud. I've been told that a
   shroud is a necessity, which I understand.
   >>>Not to put too fine a point on it, but that is not strictly true.
   It all depends on the configuration of your radiator currently.  Do you
   have it in the stock position, with pusher fans?  If so, the car came
   from the factory with two side pieces and a top cover, which helped
   ensure all air flowing through the grille would be forced through the
   radiator and not spill around the sides.  If you don't have those, you
   definitely owe it to yourself to get them.
   Do you have your radiator tilted forward, with sucker fans?  If so,
   it's still important to shroud the sides and top as much as possible.
   Aftermarket sucker fans are pretty powerful, and while there is perhaps
   something to be gained by fitting the back side of the radiator with an
   all-encompassing shroud, there is also something to be lost, as at high
   speeds the air can stagnate because it can't escape quickly enough due
   to the blockage formed by the shroud.
   Johnny Woods uses Flex-A-Lite sucker fans with integral shroud on his
   car, and he experienced high-speed overheating that he attributed to
   this problem.  He cut holes in the shroud and fitted hinged flaps that
   blow up when the pressure behind the radiator becomes excessive, and
   that fixed his problem completely.
   >I've had it for about 12 years now - no leaks.
   >>>Be very happy.  They have been known to leak, especially the early
   ones.  Sometimes the radiator is so large that it physically touches
   the body, and when the body flexes it bends the radiator and causes it
   to leak.  As long as it is properly mounted, with rubber isolation both
   at the bottom and the sides, it should be fine.
   So if you have a radiator that isn't leaking, why are you talking about
   changing it?  The Fluidyne radiator is more than you need, as long as
   the system is properly bled and the fans are working etc.
   So what exactly are we talking about here?
   >The rumblings on The List lean towards a unit by Dennis Quella(?) -
   don't know the correct spelling or the company, but the last I had read
   from someone was just to get his radiator and abe done with ita.
   >>>That was, I thought, a laughable suggestion to spend $2000 to fix a
   $200 problem, of a perfectly good radiator that had sprung a leak and
   just needed to be repaired (which it subsequently was).
   >I think it was a double-pass (I guess that's good) - and I assume it's
   shrouded.
   >>>The DQ radiator made by Ron Dennis is fantastic, no doubt.
   >Another side of me asks - which is better - copper or aluminum? And
   Why?
   >>>Aluminum's chief advantage is that it is lighter.  However, the
   disadvantage is (supposedly) that it doesn't shed heat as well, so for
   equal heat-shedding performance, an aluminum radiator needs to be made
   larger, which means it holds more water, which means you gain back much
   of the weight you supposedly saved once it's in the car.
   The chief disadvantage of aluminum is that they are normally not
   repairable.  The discussion last week centered around a high-quality
   brass Hall radiator that had sprung a leak; a crooked shop quoted $600
   to repair it which is as much as it costs to replace it.  He took it to
   an honest shop and they totally restored it for $250.
   When you are driving down the road and your radiator springs a leak far
   from home, you can normally get a brass radiator repaired locally
   without much trouble.  When an aluminum radiator picks up a rock and
   springs a leak, you take it out and throw it away. :<(
   > I know the copper units are heavier, but I am not concerned about
   extra weight. I am familiar with the company  - Brassworks - they have
   been at it since the early 1900's. Ken and Lela MacArthur had mentioned
   Brassworks in July. So - here we go - I know the discussion will
   generate a fair amount of opinions - which I always welcome, since it
   will generate more questions too. Looking forward to hearing from all
   the experts - i know you are out there.
   >>>You will likely get differing opinions, and that's fine.
   However, I would say that you are talking about replacing your radiator
   without first identifying exactly WHY you are talking about replacing
   it?  If your Fluidyne was leaking, that would be an automatic
   response.  But if it's not leaking, what is your issue?
   Overheating at slow speeds but cools fine when going down the road?
   That's either poor fan performance, wrong thermostat (Windsor instead
   of Cleveland), or air in the system.
   Overheating all the time, even when going down the road?  Almost
   assuredly air in the system.
   Neither condition requires a radiator change.  If you had a stock,
   original radiator that was visibly leaking and whose fins had separated
   from the core, for sure you would want to replace it.  As it is, IF you
   even have a problem, it's a maintenance issue.  In fact, changing the
   radiator is likely to make the problem worse, not better, if when you
   refill it you don't bleed it properly.
   So please, tell us exactly what is prompting this discussion.
   Cheers!
   Mike