How to mount radiator fans?

[iOnic]

Manufacturers spend time and money fitting a part that is only 1% functional. Yup. I guess that explains my S14 overheating all the time with the shroud missing (previous owner) and having no trouble with the shroud back on.

For what it's worth, I've built several shrouds like yours on everything from earthmoving equipment to race cars and never had a problem with one. Even on half size radiators with a single small fan. 3 of my cars run a similar setup

[MrOizo]

Here is a pic of the flaps i was talking about.

There are quite a few cars that have this one their radiators.
The flap seems to be a rubber sheet. This example has them at the top and bottom.

When cruising and plenty of air flow through the radiator, fans off, higher pressure between radiator and shroud forcing them open.

When stationary/low speed, little air flow through the radiator, fans on, low pressure between the radiator and the shroud, forcing them closed.

[sergei]

To stop fan "short-cutting" air flow, you will need to seal perimeter of the fan with foam seal.

[sergei]

Manufacturers spend time and money fitting a part that is only 1% functional. Yup. I guess that explains my S14 overheating all the time with the shroud missing (previous owner) and having no trouble with the shroud back on.

For what it's worth, I've built several shrouds like yours on everything from earthmoving equipment to race cars and never had a problem with one. Even on half size radiators with a single small fan. 3 of my cars run a similar setup

Factory shroud is very different to flat piece of allow sheet. The factory shroud is funnel shaped and allows air to pass through all area of the radiator (since it is sitting a few centimeters back from core).
Was that S14 overheating under speed?

[cat007]

Without sounding like a c0ck - has anyone made a shroud like mine and have first hand experience with it being good or bad?

Would rather hear from people who've experienced it in the real world rather than people assuming they're fluid dynamics skills are elite....

No offense to those who have offered advice and ideas. All have been taken into account and (being an internet forum, and a car one at that) with a grain of salt

I see loudstealthGT-Four and MrOizo have a similar one to mine. Have you guys both tested yours on the street and/or track use? And what were the results? good/bad/other?

[Vertigo]

true, ive never messed with shrouds, but my knowledge of the physics involved suggests that you dont need one

[Stu-]

I have on my last setup - sorry no photos. Similar to yours but with a twin core cross flow radiator with a twin 10inch fan setup. No issues at all at drags even on crazy hot days (one private day I ran 34 passes, some continuously coming off return road onto track). No issue at Pukekohe although only ran open days with short sessions not long races.

[xsspeed]

That looks about as good as you will get, plenum behind the fins will help

Would be interested to see how this goes with trackwork - didn't originally see this was for a race car - if you have overheating, remove shroud, mount fans on radiator face with flat bar tabs (from the radiator support frame/mounts), and maybe duct air to the raditor/block off other air paths/remove your grille when racing

[cat007]

I'd like to seal the two lips at each side of the shroud - and thinking something like this:

http://www.customrubbercorp.com/p_u-chan/Die11-2166.jpg

Perhaps somewhere like para rubber would sell it?

[cat007]

BOOM found this.

http://www.pararubber.co.nz/product.php?id_product=395

Should work I reckon!

[loudstealthGT-Four]

I've had my car on the track twice with my shroud setup. Once with a thicker core alloy radiator and once with the standard radiator, and haven't had any issues. Although my shroud only covers 1/2 of my rad, so slightly different.

But as been said, might as well try the setup you have now and see how it goes, if it starts to get abit warm at high load/speed, then you may need to do some slight modifications. And if you dont have any issues then you can just sit back and admire your workmanship

[cat007]

Sweet.
Thanks all

I'll see how I go with the current setup.

If it overheats at high speeds, I'll make some rubber flaps like you get on stock electric fan shrouds.
If that doesn't work, I'll redesign it and make it more like a funnel.

[cat007]

Well now I just gotta get her running so I can test if this setup will keep her cool

[gmacrae]

I maybe wrong, but I'm not so sure on the flat wall shrouds. Factory ones tend to have a taper, or a fan that more closely matches the size of the rad.
Remember the fans only work whilst parked or going very slow. Air flow at speed is the main cooling effect and from those pics there doesn't seem to be much flow friendliness going on

just what I was thinking. Making the radiator cool efficiently with the car moving/working should be top priority - a big flat shroud is not helping. If it's a decent fan it'll keep cool just fine at idle without a shroud

[Looonie]

I finished mounting up my fans yesterday... What a mission that was!

[sergei]

I finished mounting up my fans yesterday... What a mission that was!

You missed one

[cat007]

I finished mounting up my fans yesterday... What a mission that was!

You're such a troll Dave.

[gmacrae]

I finished mounting up my fans yesterday... What a mission that was!

Daym son! shit is race spec!

[Looonie]

I finished mounting up my fans yesterday... What a mission that was!

You missed one

After reading all the wise opinions in this thread, I wanted to make sure the entire radiator wasn't blocked from airflow at speed... so I left a speed hole..

[DVSMOTORSPORT]

Hahahahahahahahahahahaha, I wonder how that actually worked out. Its so stupid it probably worked really well