[Vroom_vroom]

getting a parts list for a mechanical set up, is this the fan you are referring to?

also what fan clutch? any of them better than the rest?

https://www.summitracing.com/parts/o...BoCQFcQAvD_BwE

[b-man]

I used an oem 19-1/2” fan sourced from a boneyard big mid-70s Pontiac but that one is likely equivalent.

A Hayden 2797 severe duty fan clutch is what I’m using as well as a number of others here on the forums.

[HWYSTR455]

I think the fans are now repopped?

I believe you should make sure your belts and pulleys are in top condition, it is more likely to get belt slip, especially with an AC pulley. And they don't always make noise when they slip.

There are different blade pitch fans for 'performance' applications and 'Luxo-barge' apps. I believe RPM is different and it impacts clutch engagement.

Derale makes replacement clutch fans too, and they are rated to 8000 RPM, but I have never tried them, and they list a pitch of 27 degrees for all of them. They are like $25 cheaper than repops tho.

https://www.summitracing.com/parts/der-17119?rrec=true

https://derale.com/product-footer/be...7-17120-detail

Food for thought. I wonder if they make them for the repop industry or visa-versa?


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[srmmmm]

Originally Posted by JLMounce

Did the 2nd gen birds with AC come with an upper close-out like the first gen cars? I notice that from the bumper to the core, there is no upper closeouts. Now that you have two radiators to flow air through, you may be pushing cool outside air above the core instead of through the radiator.

My 1970 has an upper close-out. Lower isn't too bad, but you can see how the lower air dam would help push more through the core. Esprit model w/AC originally.

[HWYSTR455]

The 70-73s can use the molded filler panel on top of/in front of the core support. That will help force more outside air thru the cores.

The frame horns as they pass through the core also have seals, but dang they're a pain to install. Those too force more outside air thru the cores.

And finally, yes, the air dam helps force air thru the cores. The non-spoiler (non-T/A) cars I thought would get the air dam, but I could be mistaken, they may not have come out until later years.

The OE shroud actually did a pretty good job of sealing off the core, and if not using the OE shroud, you could benefit from sealing the radiator to core. My trick there is using hot water heater pipe 'noodle' insulators. You can get them in black, and different sizes, cut them lengthwise in half if you need to.

Sandwich them between the core and rad with the rad top plate not bolted and use the rad to press them in place. A heat cycle or two and they take form. It doesn't look crazy bad either if you take your time.

You could use rubber sheet stock and with the rad out place some around the core opening with the rad out, using OE type push retainers like what's used on the cowl seal, make it look factory.

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