fan for 604

[cunningham racing]

does anyone have a numbers for the 4 bladed fan that you run in a 604

[softshoe72]

Allstar 30105

[brad hibbard]

GM 405442----takes the most HP but you can't win if you can't finish

other engine builders think I'm crazy for using this fan but its great insurance

Brad

https://www.race-1.com

[hpmaster]

I agree with Brad the GM 405442 is the way to go. I have used all sorts of fans but this fan cools without cutting holes in the nose and when used with a double pass radiator on an open motor temps on the hottest nights never went over 200.

[Mod77L]

Can anyone confirm that the only difference between the 405442 and the 15-80752 is the diameter?

As far as I can tell, 405442 = 19" 15-80752 = 18"

Is this correct? Are they pitched similarly?

[stock car driver]

gm fan has the most pitch, period. It doesn't come in a 18 inch

[brad hibbard]

It's more than pitch---------
the end of the blade changes direction on the GM fan where every other manufacturer that I have seen maintains the same angle and pitch to the end (no matter the size)-
I am not sure what that little kick does on the GM fan but I feel that it is key to the amount of air produced.

I also like the fact that the GM fan is balanced

Brad

[Mod77L]

gm fan has the most pitch, period. It doesn't come in a 18 inch

Yep, you are correct. I was working off of web search results. A little more research shows that they are the same fan with alternate part numbers.

[JustAddDirt]

one is an AC-Delco part number
the 405442 is the GM part number.
I ordered the AC Delco part number off Amazon and I took it out of the box, and it had 405442 stamped in it.

[hipower17]

any differ in the price? ac vs gm?