I got a 78 Bronco with the extra cooling radiator and shroud. It had a 400 in it. I changed it to a 460 during the winter. I have a 7 blade clutch fan. The fan is way to far into the shroud. I haven't figured out yet which fan shroud I need to fit this radiator now that I have a 460. I've tried asking BroncoGraveYard and they never bothered to respond back to me. Thanks for any help.

 

Give this a read

 

I did that same 460 swap in my Bronco years ago and I have the same radiator in redroad's link above. I have been running without a shroud for over 10 years, not that I recommend that, but I'll be making my own shortly. I don't know where you are as far as fab skills. but let me know if you need plans to build your own.

 

I've read all of that before but thanks for posting it. Ive had some very knowledgeable people about these trucks tell me that the stock 400 radiator should in fact keep a stock 460 cool. My problem is slow moving traffic. It will stay cool running down the highway. I know that having the wrong fan shroud is a major problem at slow speeds. I don't have much of a budget to work with. I've been without a job for almost a year and have been selling lots of stuff just to pay the important/have to bills.

 

One thing that you can do is run the vacuum that feeds the distributor off of a temperature operated vacuum switch .. It switches the vacuum from ported to manifold vacuum at idle raising the rpms of the motor to 1100 rpms when the motor is hot which keeps the motor running cooler .. This helps solve the the temperature rise at idle ..

 

Sometimes you overthink things too. Go buy a $12 bottle of the purple stuff to put in radiator. It raises the boiling point of water and worked well for me here in Florida.

 

As you probably know Ford never offered the 460 w/ 4WD in the F series and never offered the 460 at all in the Bronco. The fan shroud you should have right now (400 w/ extra cooling) would be part number D7TZ-8146-A, marked D7TA-AA. The closest thing to what you're looking for listed in the catalog would be for an F100-250 2WD truck with a 460 and super cooling radiator. That shroud would be p/n D3TZ-8146-D and it would be marked D4TA-CA, CB.

 

Yeah I know it was never offered in the 4wd of the Dent era or Broncos. But on other forums and places on Facebook many people say the 400 radiator works fine on a stock 460 but you need a different shroud and that seems to be where the info ends. No one seems to know which shroud will work correctly. The shroud I have now is way to deep for my application. The radiator that's on it now is new. It came from another project. Ive tried different thermostats with no change. I had a 195 in it. Tried a 180 for the heck of it...no change. New hoses and water pump. Flushed the system multiple times to make sure it was clean. 16lb cap. Living in hot sticky Kentucky isn't helping either. Mid to upper 90's high humidity and 100-115 heat index here lately.

 

Mike I had been thinking the shroud that fits a super cooling 460 rad would work but didn't know for sure. Thanks for the info.

 

Damn! I misread your first post . I was thinking you had put the 460 s/c radiator in.
I don't know whether the 460 s/c shroud will fit the 400 x/c radiator or not.
Sorry.

 

Nah I'm still using the x/c. I had thought of getting a s/c rad though. I'll probably end up just saving up to get a bigger rad and correct shroud I guess. Just sucks I haven't been able to haul my tractor to tractor shows this year b/c I'm afraid it may get hot.

 

Sorry to hijack. I'm just wondering how far the shroud should cover the fan? My shroud now is completely covering the fan. It's been that way since I bought it no cooling issues. But makes me wonder. But I have the 351m and a 4 core radiator... Someone explain to me the reason behind the shroud not covering the fan completely? I'm also going to transplant a 460 into my truck. But my 351m is pretty healthy right now. So once that motor goes. It's 460 time. Once again sorry for the hijack

 

A shroud is most efficient when no more than one-half of the fan pitch projects into the shroud.

... back to Blake.

 

Elli1644 I didn't switch to a 460 just for the heck of it. The 400 had almost no oil pressure, rods knocking, no power. I got a good deal on the 460. Runs great. Just a little hard to cool right now with my setup after its been drove on the highway then you slow down for in town driving or if your just doing a lot of in town/slow back road driving.

When the 400 was in it the fan set perfect in the shroud. With the 460 the fan is pushed all the way into the shroud.

 

Have you considered going to electric fans (Mark VIII)?
The Mark VIII setup is supposed to be able to suck the tattoos off anyone standing in front of them.