fan to radiator

[m.lion]

What is the ideal distance between fan and radiator?

[merc123]

What is the ideal distance between fan and radiator?

I've always been told 3/4" was optimal.

[perfconn]

Depends on whether you have a shroud.Without a shroud 3/4 inch is fine.With a shroud it doesn't matter.

[Egoracing]

Depends on whether you have a shroud.Without a shroud 3/4 inch is fine.With a shroud it doesn't matter.

I have to dis agree slightly. If your shoud is square with a hole in it and only 2 inches from the radiator then the fan is not pulling the air thru the whole radiator as the flow is killed by the shape of the shroud. Building a tapered shroud OR if using a square with a hole in it and can get the fan back away from the radiator the air flow will be MUCH better and cool the car better. The added benifit is that if the fan is 6-10 inches from the radiator it REALLY lowers the chance of them meeting each other.

[rubbinsracin]

we run a tapered box with hole and some shrouding around the fan with it about 1/2 in 1/2 out of the shroud. we have found that if the box is about 3" deep and the fan is about 5" away from the rad cools our car the best. we wanted to run one of the Howe bolt in and go shrouds but found it didnt want to clear the rack and everything because of the position our rad is in without basically redneck engineering it with a hammer. so we just sent it back and made our own out of some leftover aluminum. but if you got the room, the Howe unit is a really good setup because it does have the taper.

[Graff Spee]

I use a four blade ridgid fan blade. I have found that two inches works well. I do not use nor do I need a shroud. When I had fan at one inch it would hit radiator on occasion. Looks like I am way off by what you guys post but thats what I have done.