85C20 Fan Shroud Questions/Issues Serp Belt

[1972C10]

Does anyone know for certain The small block fan shroud vs a big block fan shroud differences?

I have a big block shroud i had been using with a 350 and a flex fan and it was close to the passenger side and bottom but didnt hit Thats where my new fan setup is hitting It seems it is larger diameter than the flex fan i had been using

I recently changed over to the Serpentine belt setup off an 89 and the fan rubbed

My options are modifying my exsitsting BB shroud Or buy a Sb shroud and hope it works with my current Clutch fan setup

I dont mind so much the idea of modifying the one but if a buy a new one id like to know that it would clear this setup I have now Because if im going to modify one i may as welll ruin the one i already have rather than buy one then have to make it work.

If anyone has any info on the subject it would be greatly apreciated.

[piecesparts]

I just took it all off and put on a pair of electric fans. The engine idles better and the acceleration is smoother. I think that it helped a little with the gas mileage. I have done two trucks this way (My 84 GMC and the 91 Silverado)

On each I used a set of SPAL 11" dual electric fans, but you can get fans off of just about anything and get them mounted.(hard to beat the spal fans for performance) What I would look for are ones that move a lot of air, so you don't overheat. There are numerous ways to turn them on also and make sure your relays are away from any major heat source, so they don't go to an OPEN condition on you , when you need them most.

[beaterC10]

My fan is approximately centered in my shroud with a 350 with using a HD cooling option and a small block shroud. I would have assumed the fan would be in the same relative position using either a v-belt or serpentine, since the water pump is block mounted.

[1972C10]

Im thinking the difference is the shrouds I dont want all electric on the truck i just aim to get the factory aux cooling fan working.

I called New world today and talked to some arab i can get a shroud for a sb block 2 pc for 20 per side I May get that but i wonder if the 89 fan is a larger diameter than a stock style 350 fan for a truck like this

Also i have a 4 row radiator im not sure if the shroud there offering is going to work sounds like to me it would be for a smaller radiator.

What do you mean by "HD cooling option " ?

[1972C10]

Here is a pic of what it looks like

[beaterC10]

I was referring to the Heavy Duty cooling option. It was used on small block trucks with air and non air trucks as an option. It used a three core radiator.

The upper bracket for the shroud in your pic looks like a 73-80 application.

[1972C10]

Nah its original 85 454 With a 4 row I ended up trimming the area that the fan was hitting and extending the shroud with some stainless