Has anyone used a spacer for there fan to be closer to radiatior?
 

Talking with a guy at our weekly cruise night. He told me I should get a spacer to get the fan closer to the radiator.
Has anyone done this? Does it work?
Let me know.
Thanks
FB66

It's more about getting the fan placed about half in, half out from the shroud.

The factory used fan spacers in some applications.

But only with a regular fan, never use a spacer if you have a fan clutch.

With a factory clutch fan and factory shroud, you don't need Any mods.

Thanks guys,
You really helped me out.
No spacer for my clutch fan.
FB66

I hear this all the time, and it makes sense. I have a stock pump, 7 blade clutch fan (I believe is stock style), stock shroud on a 72 formula. The fan blades only sit about an inch out of the shroud. The stock mounting stuff is used and all fits well with a cold case radiator. I don't have overheating issues, but the stop setup doesn't put the fan half way out of the shroud on my car. I just find it curious that my stock setup has the fan blades only an inch out of the shroud. Seems to work fine.

I have stock shroud, 19" AC clutch fan, and correct later-11-bolt waterpump, so I have the correct 1/2-in-1/2-out spacing, BUT, my fan WILL end up closer to my radiator once my new Cold Case comes in, since it's thicker. ... .. assuming they ever ship it. :rolleyes: Word of advice: don't order a CC rad through Firebird Central since they order it to be shipped to you from CC. You won't even get a tracking number, and it's been almost two weeks in business days and I have no earthly idea where the thing is or if it even shipped, and my Trans Am is just sitting in the garage with dripping radiator hoses hanging off the engine with its proverbial thumb up its butt.

But yeah, the 3-row Champion that came on my 79 T/A isn't as thick as the factory radiator, which would've been a 4-row Harrison since my car is equipped with factory air conditioning. You can tell because the 4 shock-absorbing/insulating pads at each corner are for a 4-row and kinda just jiggle around and are loose on the Champion radiator, and there's a good 1.25" gap between the radiator and fan shroud that I had to seal up. So check your rad and see if you maybe have an incorrect one. The new CC will close around an inch of distance between the radiator core and fan.

My 2 row (1.25 inch tubes) cold case is actually no thicker, maybe even a little thinner than the 4 row Harrison I replaced. In any case, the radiator doesn't locate the shroud anyhow. The shroud bolts to the car so is fixed to the frame and that sets the relationship between the fan and the shroud. I have the stock AC pulleys and it doesn't look lie the clutch fan setup would allow for the fan to be moved closer to the water pump flange. I just find it curious that the alignment between the fan and shroud is "wrong" on what appears to be a totally stock setup. I don't think it's the wrong shroud.

Yeah, makes sense. I do know objectively that the CC is thicker than this Champion I have on my car right now, since I compared the measurements advertised on CC and Champion's websites. These little bits of space add up, and having the radiator at a more "correct" distance from the fan due to its thickness may help some, and also may make the fan clutch thermal coil more sensitive to the temperature coming off the rad. After all, radiation is one of the most dramatic and sensitive methods of thermal transfer. A tiny distance away makes a huge different in how much heat is transferred.

Not all fan clutches are created equal.
The fan bolts to the clutch, the clutch has the STAND OFF with flange that bolts to the Pump.
Have seen so called "direct fit "clutches with a too long shaft more than once.

That could be.

If it helps ease anyone's mind at all, I find the distance of the blades in relation to the shrouds don't make a whole hill a beans difference.

I (or anyone that wants to) can look at several cars here in the stable. All with their factory clutch fans, factory shrouds etc.... Each car is a bit different in spacing, some have the fan all the way in the shroud, some have them maybe an inch out of the shroud, some are "maybe" half in/half out. There is no rhyme or reason to it.

Not one of them exhibits any type of heating issue at all and work perfectly fine. In fact some would say they run too cool, lol. So I just stopped paying attention to where the fan is placed a long time ago.

In fact, one car here with a nice running 327 in it doesn't have a shroud at all (factory). It just has the fan spaced close to the radiator, maybe an inch away. I can't get that car over 180 degrees no matter what I do with it. The funny part is now the aftermarket has stepped up and actually makes a small custom molded shroud for these cars. That's nice, but I just don't find a need for it.

When I was sent to GM schooling on Cooling, brakes, exhaust, carburation for ASE cert. I saw and learned a lot that I thought I knew.
( Being young and stubborn and knowing it all based strictly on common sense)
Cooling, I learned how and why the fan shroud was made and what it does. I wish I could have the giant poster on the wall there of engineers
standing around a car ( 1960 Pontiac I believe) and some with clip boards, and others reading all of like 30 different Vacuum gauges they had
on nipples around the fan shroud.
What I was taught was that keeping the fan blades furthest point, or edges closest to the shroud IS most efficient.
In most cases the fan is just barely inside the shroud.
That said they said the cooling was a total package based on the weight of the car, and the CR of the engine.
Cooling "systems" were designed to handle up to 18% excess heat produced for desert use.
So, its totally possible that "most" GM cars produced that run on original, or equivalent fuel ( lead additive ) and no alcohol
will run fine with some fluctuation in the fan distance in the shroud.
Low CR or lower rpm engines dont need a fan shroud, like a cheby inline six, or a 2bbl 327 .
Get into 4bbl, and add on AC and a lot can change in the cooling system
If anyone doubts the fact that this system uses the LEAST Horsepower, and does the BEST job, look no further
that Hot rod TV. The engine masters had all sorts of cooling set ups at a Dyno, and made their bets..
They all lost. I find it amazing how many people think that the factory engineers didnt know what they were doing.
Air doesnt do sharp corners....The same folks that want their heads all smoothed and ported will run a hideous restrictive cooling system
because its in a catalog... ... Some things ( not all) are best left stock...

One thing I've generally left alone, whether it's a stock engine or a 700hp engine, it's the cooling system.

I might step up to a nice radiator but that's about the extent of the cooling system mods.

I'm sure there is merit to spacing the fan in the shroud, not questioning it. I just don't give it much thought these days since owning several cars of various brands and finding not one of them the same as far as the "general rule" of fan and shroud spacing. They are all drastically different, and it doesn't seem to have any affect on any of the cars here in the desert heat.

of course a 3 row isnt as thick as a 4 row, they make 3 row isolation pads for 3 row radiators. as stated above, the shroud location is the same regardless of rad size & the factory 3 rows had a gap between the rad tanks & shroud edges & still cool ok.

were you having issues with the champion 3 row? i recall some of your other posts about cooling issues & changing water pumps etc. i have the champion 3 row in a ~520hp 10.75:1 stroker engine in a 72 firebird with a china made PRW aluminum pump & worn out stock clutch fan & it keeps the car cool in every situation from hot humid summer stop & go city driving, to drag racing almost back to back runs & sitting in the staging lanes for 15+ minutes some times. aside from some rare quality issues some may have had, which is expected with most any aftermarket parts these days, im very happy & impressed at how well the champion radiator cools this engine. they rate the 3 row to 700+hp so just curious why the 3 row wasnt sufficient in your lower hp car.

& BTW, almost all companies drop ship products like this direct from the manufacturer, they dont keep these parts in stock for the most part. you should be able to call or email firebird central & get some type of shipping confirmation, but its possible CC is backed up with product delays like almost every other company today.

Did the factory pound down the divider plate? That seems to be something that comes up a lot.

Well, it's very simple, really. You see, I'm an idiot.

I only got as far as burping the radiator after refilling the car with coolant after installing the very tightly clearanced Flowkooler I got before I decided, "hey you know what, let me also replace the radiator just in case this one isn't enough radiator for my car." The rest is history.

And this is aaallll based off of a couple occasions this Summer where my car crept up to 210 or 215 at idle or at stoplights in 90 degree Florida humidity without AC running. Discovered I had a stamped impeller pump with a .200 clearance, so that could've been a factor, but I never had a chance to really put this new Flowkooler to the test before I pulled the Champion rad and ordered the CC (which is on backorder btw, that's why it's taking so long - found that out today).

Let's just say if something that bothers me happens, I always bring a machine gun to a knife fight. Maybe nothing is wrong with the Champion rad... but I just want to try something different with a little more capacity. And sadly, if my car running hot problems are resolved after I get the new rad, then I won't know if it was it or the water pump that was the issue because my impulsivity... but hey at least I won't deny im a dumbass

Coincidentally, the first time the car ever got that hot this summer was after I put in a new alternator, after which ive had belt chirping/squeeling if I bring the car to high RPMs. Wonder if they're related, cuz for the most part if I just drive the car around normally and shift early, the temp never gets past 185 or so and it immediately drops to 175ish once I start moving.

LOL. great reply! yeah i do some of that a lot too....

just a suggestion but since the CC is on back order until who knows when, you could easily stick the champion back in there to be able to drive the car & to test your new pump to see if it fixes the hot issues you had & the champion is sufficient. if all is well & you dont got money to burn you could always cancel the order for the CC. based on my experience with the 3 row champion & 2 other friends that used the same rad on stroker engines in their 2nd gens i would say it will easily keep your car cool if there arent other problems going on causing the overheats. the 3 row is rated far above the power youre making.

also i dont recall what T-stat you have but a 180 or even 160 in florida would help over the stock 195. & a trick for burping air from the system is to use the T-stat hole to fill coolant right up to just under flush with the opening with the rad & bottom hose installed, then install the t-stat & housing & upper hose & fill the rad the rest of the way, that will get most or usually all the air out of the engine & system. doing it that way i have never had to actually burp the system.

its quick & easy to install the rad & you could buy some 3 row pads so its more secure... just a suggestion to not buy something thats not needed. hope it all works out for you!

In theory and by design specs, the factory shouldn't need too. The impellers on the original factory water pumps should be spaced correctly to begin with.

In theory...

a) fan should be 2/3 of the way into the shroud.
b) have never had a GM car that did not have a shroud. Longest was on a 70 Grand Prix.