radiator- cooling

anyone know if there are Modern OEM radiator /fan sets that will fit 72 duster?

Reason I ask is because the fans are so good on the OEM units and, in general they cost less than aluminum and in many cases, weigh less.

Just one of the things i'm pondering on weight/cooling.
Just a bracket car btw.

thanks again.

Call Glen ray and talk to Bob.

The HHR fan was pretty popular around here for a long time. Champion and others sell a fairly economic replacement aluminum radiator for most old Mopars. Seems like a good combo for many here

I'm running a 26" 3 core Champion from Jeg's with a 12" shrouded electric fan and it works great: http://www.jegs.com/i/Champion-Cooling-Systems/166/CC375/10002/-1

ford contour dorman 620-104 depends on the width of your radiator. its less than 3.5" wide

I have a fan/shroud from mid 90's Chrysler mini-van. Fits and will blow the radiator cold. This fan will draw 40+ amps...

One of my friends here runs Chevrolet’s stuff ( I know, but I like him anyway ) and he runs fans and pump until he stages then shuts everything off.
He works his system to make sure he stages at 165 degrees.

The conversation came up as I mentioned I used to use an alternator cut out switch so alternator was “ no load “ when racing .
He does similar with a mater switch that cuts off pump/ fan and alternator when he stages.
Kicks everything back in at end of run.

I cannot find anything in rule book to prohibit this.
Thus my question on the radiator/ cooling , thinking an OEM unit might be lighter and take off temps faster that the aluminum/ after market.

Does anyone here do similar with temps/ cutting off pump/ fan for your pass?
Secondly , what temps do you like at staging ?

Thirdly - fan shroud : ones I have looked at for puller fans completely close off back side of radiator , wondering how much air dam/ drag issue that creates ?
It would seem that letting air flow through radiator on a pass would be less drag in the car.

Thoughts/ experiences?
We will go ahead with a champion , 3 core seems about right .
Fan/ shroud design I’m uncertain on.

I still have my stock radiator out of my 1972 (340) Duster sitting here that I had recored 30 plus years ago. A neighborhood shop did the work for me and it fixed all my heating issues. I tried selling it after matt and I switched to alcohol but typical mopar guys wanted it for next to nothing so I leaned it against the wall in my basement. Who knows maybe I will build a street car after I’m done racing.

I try to stage exacly the same way every time, including keeping the engine temp the same. I use the fan to keep the water temp as close to 140 as possible before entering the water box. I chose 140 as it’s an easy number for me to maintain in the lanes. If I could keep it lower I would. With all that said - I haven’t noticed a difference in ET with water temps anywhere between 120 and 170.

Interesting point about killing the alternator and assessories. I’d be concerned about heating things up too much by the end of the pass but can see how it could help ET. I may have to try it.

I use to kill the alt but a couple of years of
doing that I didnt see any change in ET and went
back to keeping it on.. I use to use a L body
rad and the small fan that was on it.. on my
Rampage I use a Summit rad and the HHR fan fit
my rad perfectly.. I do want to add 2 spring
loaded flipper doors to it for a bit more flow
I use a 2 row 3 pass rad

I don't currently have any " load vs drag " numbers to present , however, Back in the day- it made a difference.

if we look at amp draw numbers for fan, water pump and lights , lets say its 55 amps- put an alternator on an electric motor and look at the drag on the motor with a 55 amp load- its significant.
how much drag with modern alternators - im not sure.
I would think we could find the data somewhere.

When we go back to chassis Dyno , I plan to test load vs torque/hp at rpm scales.
My "guess" is it effects us most at shift points which means it effects driveshaft speed recovery.

might not be enough with todays alternators to fool with, then again, might be a slight consistency improvement in always running "no load " vs varied charge loads.

just the thoughts of an old bald headed guy.

ok- at 50 amps of load it costs 6 to 8 hp with windage costs.

if we had a clutch system that would disengage the shaft- we could see real differences .
something like a blower clutch on smaller scale would work it would seem.
The math i'm looking at indicates we could be seeing losses of close to 20 hp depending on battery condition, amp load and alternator windage.

Looking at the math - doesn't seem to be significant with modern components.
im still going to test it on a chassis Dyno .

Its the draw you need to worry about.. if your
draw is low the alt wont do much at all(low
out put)

Just throwing something out on this from looking how my stock Neon is cooled. It has one electric fan, and a shroud. On the shroud there are a lot of windows with a rubber flap. At low speed the fan does the cooling, but at speed the fan stops, except when the a/c is on, and the wind pushes the flaps open and that does the cooling. I'm sure this concept could be useful at the strip also. Let the fan do the cooling in staging, and turn the fan off, then let the wind cool during the run.
My $1.50

Makes sense.

I'm in need of a new radiator as my OLD Summit w/epoxied cores is leaking, what's the part # on that Mike so I can order one up...........

Why on a bracket car would you worry about cutting the alternator on a run. It is a shoe polish race so how could it be on any benefit? FWIW we run an alternator on the heads up car it sees 10,000 rpm on a regular basis and keeps all the racepak and ignition stuff happy. Just a question, as I cant see any benefit from turning it off.

If the alternator is consuming 8 - 10hp that might actually show up on a timeslip, which makes us ET chasers happy.