[leeklm]

Hello,

I noticed a price discount on the cold case with single electric fan and shroud at Summit, part #CHC11AK so was thinking of purchasing a little sooner than needed... anyone have experience with this setup in a higher HP application?

The 600hp aluminum head motor is from my 73 GTO, which cooled easily with factory style 3 core brass radiator (was a big rad!), shroud, and clutch fan. Of course the clutch fan moved way more air than a single electric fan would, which is my concern. My limited experience with electric fans has not left me impressed, but would like to go that route for this non AC street/strip build.

While I am in MN, it does get to feeling like TX a few days out of the year, so want the cooling system to work on a hot humid day at the track!

Thoughts?

Sent from my SM-G965U using Tapatalk

[Ccass]

I'm sure you'll get some objective feedback but I just wanted to point out that the single 16" fan was chosen for a specific reason. A lot of owners think a crossflow should automatically have 2 fans for better cooling. For the 1st gen F-body radiator, you can't fit dual 12" fans which would be optimal. However, if we were to install dual 10" fans that fit, the cfm is reduced dramatically. Example: dual 12" fans is 2800 cfm. Single 16" fan is 2500 cfm. Dual 10" fans is less than 1000 cfm. As a general rule, anything smaller than a 12" fan doesn't pull nearly as much air. There are exceptions but those exceptions need a ton of amps, are very loud and still won't pull 2500 cfm.

[Speargun]

Here's a review of 3 radiators. Champion vs Eastwood vs Cold Case Radiators

Short version: Cold Case cooled the best.

I ended up using two Spal extreme duty 11" fans, which are advertised as 1605 cfm each, but a single large fan would probably be a better option.

If you go electric, spend a little extra and go with a Spal fan.



Here's a pic of a Lincoln mark VIII/Taurus type fan that moves a HUGE amount of air. This was my first choice, but due to the way I designed my motor mounts, the engine sits forward a little and the fan motor hits the water pump pulley. An engine in the stock location should have better clearance.

[leeklm]

Thanks speargun, I did see your comparison- nice job. Did you fabricate your own shroud for the electric fan? I am not adverse to doing so, but hoping to find something that was "built to fit".

Do you still have the ford fan, or have you sold it?

Does anyone know what brand/model of fan the cold case folks provide? I was also looking at a Derale 2-spd fan that looked good.

Sent from my SM-G965U using Tapatalk

[AG]

I run a Mark VIII fan on my '67 FB race car with a Griffin 2 core radiator that has a core about the same size as the fan. Works very well, on a 90°F day gets to about 190-195°F at the end of the track. I use a 75 amp relay for the fan, those things move a lot of air.

[chrisp]

One of the best cooling items to have on 67-69 F-body is the upper rad. R&L baffles & the lower baffle on the core support with a nice fan shroud . My 68 A/C 400 bird could idle all day @ 180 & had a strong pull of air through the grilles @ idle .

[leeklm]

Picked up a Mark 8 variable speed fan for about $100 on Ebay. Fits the 1st gen rad very nicely! Also bought one of these controllers, which come highly recommended on some internet cooling threads.... hopefully the engine clears, but it should

Sent from my SM-G965U using Tapatalk

[leeklm]

Like we say in this hobby... it's always something! I was optimistic that the Mark 8 fan & shroud would clear, but it does not. I could trim the shroud about 5/8", which might clear, but then fan is within an 1/8 to 3/16 from radiator core . Not ideal.

Now I am thinking either the aftermarket shroud and dual fan setup, or maybe electric water pump. Car will not see a whole lot of street use anyhow, so electric might be money better spent than new fans...



Sent from my SM-G965U using Tapatalk

[Ccass]

Originally Posted by leeklm

Also bought one of these controllers, which come highly recommended on some internet cooling threads....

Where did you get that controller? Brand? cost?

[Ccass]

never mind. I just found it. Sorry.

[Jonsey]

I've got a 69 Firebird with the Mark 8 fan. I had the same problem with water pump interference as you. My solution was to just flip the fan upside down. Works great for me.

[leeklm]

Good idea, I did not realize the fan was that much off center, but just measured, and it is. I can also move the fan all the way towards driver side of rad, which will buy another 1/2".

Do you recall how close your fan center hub is to the core? Mine is about 3/4". I could trim 1/4" off shroud and gain just a little more clearance.

All in all, it may just save me from spending $380 on an electric water pump!

Sent from my SM-G965U using Tapatalk

[Jonsey]

I can't remember. I did trim it a little, but I left a bit of room so the fan wouldn't be sitting right against the radiator. It's close, but it doesn't touch.

I had an electric water pump at one time myself, but I like having power steering, A/C and the simplicity of the mechanical pump.

The mark 8 setup seems to have completely eliminated my overheating. I also upgraded to one of those flow kooler water pumps as well.

I have a two speed mark 8. I don't think I've ever heard it kick onto the higher speed.

[leeklm]

Thank you again for the tip! I cut 1/4" off the shroud depth and flipped fan over. Plenty of clearance now!

Sent from my SM-G965U using Tapatalk

[Jonsey]

It looks great. I think you'll be really happy with the performance.