General cooling discussion, rad, fan, coolant, shroud, etc,

[tarafied1]

Okay, I am thinking of my car specifically but this stuff may apply to others. I have found a great article on Hot Rod's website...
http://www.hotrod.com/techarticles/cooling_system_tech/index.html
Basically what I read is:

- Mid-’60s vintage radiators made of brass and copper typically fall in the 10- to 14-fin/inch category (low fin density)
- engine-driven fans with deep pitch-angle blades work best with low-fin-density radiators, while electric fans with shallow pitch-angle blades tend to work best with high-fin-density-count radiators.
- brass and copper radiators offer thermal conductivity advantages over aluminum radiators, they are limited to a maximum coolant tube diameter of 5/8 to ¾ inch.
- Aluminum radiators can be built with tubes up to 1-½ inches in diameter. The larger tubes allow the radiator manufacturer to place more fins-per-inch, which improves the radiator’s thermal efficiency. That reduces the thickness (and weight) of the radiator and also improves airflow through the radiator.
- For example, an aluminum radiator with two rows of 1-½-inch coolant tubes is probably more efficient than a four-row brass/copper radiator. Not only would the brass/copper radiator be heavier, but its added thickness would present a more restrictive path for the air to travel, especially at low vehicle and engine speeds.
- electric fans should always be mounted behind the radiator for optimal cooling. These fans do a better job of creating a low-pressure area behind the radiator than they do of pushing air through a radiator.
- Generally, engine-driven fans are more efficient than electric fans

So what I understand is that I have the worst scenario for low speed cooling. I have a brass/copper 4 core radiator with an electric pusher fan. The pusher fan is at least 10% less efficient than a puller and some level less efficient than a mechanical fan. In addition the radiator itself is less thermal efficient than an aluminum radiator.
What I believe I need is an aluminum two core/row radiator and a puller fan to improve my low speed cooling, right?

[Fast68back]

I would say yes, aluminum and either one big fan or two smaller fans. You could always get one of those bad@$$ Fan/Shroud setups like Darreld has, but you may need to mortgage the house....

[tarafied1]

I would say yes, aluminum and either one big fan or two smaller fans. You could always get one of those bad@$$ Fan/Shroud setups like Darreld has, but you may need to mortgage the house....

:lol

[Horseplay]

Here I thought we were trying to find you a fix on the cheap!

Spring for a GOOD two row aluminum radiator and I'd say you would be good to go. I'd recommend it be a cross-flow unit too. You may even be able to stay with the pusher fan.

I recommend these guys. http://cgi.ebay.com/ebaymotors/NEW-Mustang-64-65-66-Aluminum-Radiator-V8-Conversion-/320533890164?cmd=ViewItem&pt=Motors_Car_Truck_Parts_Accessories&hash=item4aa14f0474
(Not the one you need but you can search from there.)

[daveSanborn]

The pusher fan is at least 10% less efficient than a puller and some level less efficient than a mechanical fan.

I'm not sure where you got the 10% figure, but I'd put money on a pusher being closer to 30% less efficient than a puller..... and electric fans in general are usually about the same.... 30% less efficient than a properly spaced, shrouded mechanical fan.

If you replace your 4 core brass (thick) radiator with a more efficient 2 core AL (thinner) radiator.... will it free up enough space to mount dual puller fans?  Keep in mind that using dual puller fans requires less clearance than a single electric fan because the fan motors will be offset to the sides of the water pump snout/pulley.

Your car has a cooling issue that's not going to fix itself.  You WILL eventually address this issue regardless of the PowerTour.  You've been planning for the PowerTour for what?   Two years?  Why not fix the cooling issue with your car before the PowerTour and be done with it? 

[68EFIvert]

I would say yes, aluminum and either one big fan or two smaller fans. You could always get one of those bad@$$ Fan/Shroud setups like Darreld has, but you may need to mortgage the house....

I don't know about a mortgage but it is something you may want to have sex with.  :lol  Scott is a great guy to work with and his prices are really not that bad.  wizardcooling.com

He does very nice work.

I would also recommend for you to look at a good electric water pump.  My engine actually runs cooler in traffic than it does driving down the hwy.  I think that is because engine heat is less when idling since the rpms are lower/less heat from blower ...........

[tarafied1]

cheap would have been nice but I don't expect cheap will work, and Dave, the 10% was quoted from the linked article. I agree it needs to be addressed and won't fix itself. I just thought if I could get airflow at no or low speed my set-up would work because 99.9% of the time I'm fine. I rarely ever get stuck in traffic but on the tour it sounds like it could be everyday!

do you have dimensions on this thing? I think what Dave says is true, a two row should allow for dual pullers, this thing looks way too big (thick) to fit without cutting the core support (with my 429).

[Horseplay]

Get the good two row aluminum from the company in the link I provided (or something alike from someone else) install it and see where you stand. If you are really just on the edge, that will take care of your problem. You could then measure and see what kind of room you might have for a puller fan set-up as well.

Moving from your current four row to a good two row aluminum will yield a good difference in cooling capacity. Just make sure to get a unit that is welded not glued and is of correct design (cross-flow would be best).

[tarafied1]

thanks, I'm heading to St. Paul and I leave next Thursday, I hope I can get this all done before I leave (or just get the parts and I can do it one night at the hotel).

[garner67]

I like these guys on eBay...

Universal Parts, Inc

I purchased a custom radiator shroud from Universal for my Griffin radiator.  However, if I were to start from scratch again, I'd probably purchase a radiator, e-fans and shroud as one package from these guys.  IMHO, the Griffin radiators are over priced.

[silverblueBP]

I like these guys on eBay...

Universal Parts, Inc

I purchased a custom radiator shroud from Universal for my Griffin radiator.  However, if I were to start from scratch again, I'd probably purchase a radiator, e-fans and shroud as one package from these guys.  IMHO, the Griffin radiators are over priced.

+1

[Fast68back]

Craig, do you have your headers wrapped?

[68EFIvert]

Total depth is a little over 4" IIRC.  The shroud is right at 2" deep.  It is 25 1/2" wide. 

[gwstang]

I've got a 2 row alum. radiator ($160) from Jegs and using a 2 speed taurus fan ($15) from picknpull with a programmable controller ($60) from summitracing.  Mine never gets hot in traffic or otherwise!  The taurus 2 speed fan will pull small animals and little children right thru the radiator if you don't watch it...lol.  I'm not even using a shroud and don't really need one with this setup.  Now when I add the a/c unit I might then.  I set the low speed to come on about 200 deg and off at around 190.  Then the high speed from 210 down to 205 deg and it works damn well! 

[tarafied1]

thanks for the recommendation guys...

Craig, do you have your headers wrapped?

No but they are ceramic coated, Stan at FPA said it would drop the under hood temps.

I have just been trying to convince myself of what everyone else seems to know. My cooling system works fine at speed, I have a 3000cfm fan and a mild 429. Ford built cars with 429's and copper/brass rad's and they didn't run hot in traffic. I know there is no room under the hood for airflow but the 390/428 FE motor is the same width and used the same radiator I have. The only difference is the factory used a puller fan (mechanical). Like Dave says, the pusher must be horribly inefficient at moving air. As you all have probably noticed I never have any money so I hate to spend it when I do have some, if I could make the airflow I know the radiator will cool the engine.
My wife (bless her) has used a bunch of my hotel points to get all out rooms except two nights free on the power tour so I could use some of our budgeted funds to get a aluminum radiator. So now I need to crap or get off the pot!
I know what would Sanborn would do, how 'bout the rest of you guys? Try to get airflow/remove underhood heat, or just spend some money and be done with it?

[AzPete]

Fix it right or stay home...............

[Horseplay]

Has your engine been rebuilt? More specifically, has it been bored? I know next to nothing about 429s, in particular, but many engines have thin walled cylinders to begin with and boring only makes them run hotter. I only bring it up in response to your point about BB mustangs and stock radiators. May answer some questions for you.

My opinion (since you asked)...get an aluminum radiator and be done with it. All the ideas and tips posted to help remove underhood heat have been good and will give some benefit but I seriously doubt they will "fix" the situation completely. For a couple hundred you can get a great cross-flow from the source I posted earlier. That alone should be enough to solve the issue. You may also benefit in gaining some fan room. Maybe even enough to go to a pull vs push set-up. At that point, there are plenty of cheap ways (junkyard...) to make a fan improvement if funds are tight.

[apollard]

Well, I offer a diverging viewpoint-

Your brass rad is working. Why? Because it rejects heat quite well when you have good airflow (when moving). That is also when the engine will be stressing the rad the hardest (ie, more heat from the engine). Get the airflow at idle close to the airflow at speed, and you will have no problem. Changing the rad material will help, but without enough airflow, no heat transfer. Period

BTW, the mechanical fan will not do that - it turns slower at idle.

I would go with the Contour fan - $100 bucks new from a local source, two fans, a good shroud that will fit your rad with little work, and a hurricane under the hood when they cut on.

[Horseplay]

Sure more airflow may fix the issue but space constraints have prevented the use of a higher CFM puller fan. I for one am also not a fan (pun intended) of electric fans than are loud enough to be heard over the rumble of a V8. This four core brass radiator is not going to compete evenly against a well designed 2 core aluminum cross-flow. It's just not.

I would also think the new aluminum piece would be thinner and may allow him to go to a puller fan set-up.

Oh, and there is always the bling factor!

[tarafied1]

I want to fix it right, but as Apollard said the brass/copper rad works if air flows thru it. In the photo you can see there is no room for a puller fan (thanks for sharing your pics though). What I read in the linked article is that the aluminum radiator works better with a "low pitch" fan, i.e. electric fan. There is the benefit of being narrower and maybe (MAYBE is key) I could use a puller. My biggest concern is spending the money on new stuff and having the same problem. If the hot air can't get out from under the hood the AL rad won't work any better, or will it?
Oh, and Horse Play, the engine is rebuilt, the 429/460 blocks are thinwall casting. I was lucky the block was in great shape and didn't need to be bored. I am running TRW Forged flat top pistons but the CR is "stock" at 10.5:1
I think the biggest issue is the underhood temp. I was in line for an hour or more last June to get into the Hot Rod Reunion in 97 degree heat. The temp gauge rose but I didn't boil over. After about 45 minutes though I got nervous and popped the hood, this seemed to help because the heat could escape.
I'm not worried that the car will "overheat" but that I will be subjecting it to this condition many times in the upcoming road trip.

[tarafied1]

I would also recommend for you to look at a good electric water pump.

how reliable are electric water pumps? I've only seen them on race cars, would it hold up to everyday use?

[Horseplay]

how reliable are electric water pumps? I've only seen them on race cars, would it hold up to everyday use?

not recommended for a real driver.

[68EFIvert]

how reliable are electric water pumps? I've only seen them on race cars, would it hold up to everyday use?

They are rated at 3000+ hours of use so I am not worried.  I will never put that many hours on my car and if it does go out you can replace or repair the electric motor.  Get a good name brand like Meziere and stay away from Chinese crap and you should be fine.

[daveSanborn]

Craig,

To gain clearance for a shrouded mechanical.... or better yet a dual electric puller fan..... you can cut the "recess flange" off of the radiator support that is forcing your existing radiator to mount so far rearward.  Removing the flange/lip of the radiator support and moving the radiator forward should give you close to 1.5" of additional room.  That's more than enough for a mech. fan and should be enough for a dual elec. puller.

It's not like you haven't made permanent modifications to the car already.....

[Fast68back]

You know Craig, I was just reading this and noticed your avatar pic..... take a look at your grille, maybe something in front of the radiator is restricting airflow......