I'm revamping some of my cooling system, ditching the single factory with a higher CFM single 16" flex-a-lite fan mounted to an aluminum fan shroud, both the radiator and shroud are from Champion. Champion doesn't offer a single fan shroud any more for the 82-92 f-body radiators and they just so happen to have one single 16" radiator left so when ordering they didn't have any pictures on their website. The shroud that was delivered has 4 louvers, one in each corner, I was not expecting this and I was planning on adding the rubber flappers in each corner.
On to my question....would there be any benefit to cutting the holes and adding the four flappers even thought the shroud has the four louvers?

Am I better off to run this with just the louvers?
Add the flappers with the louvers?
flatten out the louvers weld the seams closed and run just the flappers?

Flappers

This is not the shroud that I have but it's similar, the shroud I have has only one louver in each corner.
Champion radiator shroud

 

I would prefer the flappers as they should close when your car is not in motion and open at speed. At least that how i think they work. The louvers might be a compromise of the two (open/closed)
I made my own shroud out of aluminum sheet w/ two spring loaded trap doors. Mounted to the upper/lower OE shrouds and a spal fan modified to fit in the OE fan brace. Works quite well.

 

I remember when you first posted this, I thought it was well done with the fairly complex bends.
I decided to add the flappers, figured more air flow can't be a bad thing, once I get the fan shroud modified, I'll post some pictures.

 

I think the flaps are the way to go, post up when its done.

 

Here's what I've got so far, this weekend I'll get started on removing the radiator to install rivnuts to mount the fan shroud.

flaps and 16" Flex-a-lite fan

Lexan template to consistently locate pattern on the aluminum panel to be drilled then cut on all four corners

Holes drilled the cut with a air reseparating saw, probably should of done this at work using better tools, lines aren't as straight as I'd like but with the flaps in place they're good enough.

SPAL flaps in place


Some fancy counter sunk washers just because, the fan mounting hardware is threaded into rivnuts installed on the fan shroud.

 

Nice work, looks good. I like the counter sunk washers too. Are you gonna close off the louvers?

 

I've considered it, is there anything negative with keeping them, not sure if it's worth spending the time on flattening them out and tigging them closed?
what's your thoughts on that?

 

I think they could help some when your car is stopped, but at speed they could bleed some air out that could help push the flaps open, if that air wasn't diverted thru the louvers. Maybe leave them open and see how it functions afterwards. Is there only one louver per flap?

 

That's probably what I'm going to do, leave the louvers as is and see how it works out after I get the car back on the road./
Yes there is one louver per flap in each corner. Gonna try and get the radiator out this weekend, I'm using rivnuts for mounting the shroud to the radiator, with the radiator in the car I don't have enough room to use the install tool for the rivnuts.

 

Speaking of rivnuts. I just got one from HF, its the Doyle brand. So far ive use it twice, but very pleased with it. Though i know little about types and brands. Which brand do you have?

 

Fastenal brand, they are our fastener supplier at work, we carry a small supply of various sizes in stock at work along with the pneumatic tool to install the rivnuts.

 

Pheumatic, beats manually installing them. Now if only there was a cordless version.

 

Found this on Amazon

 

I think i saw that too. I think that also a rivet gun too. If only i knew that brand enough to trust it.

 

So I was able to get the rivnuts installed on the Champion 2 core radiator, 4 1/4-20's on top and on bottom to mount the fan shroud, radiator/shroud/fam assembly installed into the car and I'm currently working on getting it all back together.

 

Nice work and i like that top piece too. Looks very professional with the relief holes .

 

Thank you!
I’m quite happy how that turned out, I wish could take 100% credit for it, I’ve got a couple good buddies of mine that work in our machine shop at work that are also car guys, we also do powder coating in house as well

84 1LE do you know what the CFM is of the factory 16” single fan? I was searching here but I don’t think I found a for sure answer, the Flex-o-lite fan that I have is somewhere between 2,600 and 3,000 CFM I think?

 

I'm not %100 sure, but I thought i read on this forum it's around 2000 cfm.. My fan is a hair over 3k cfm, according to Spal, also 16".