will be swapping a 351W in the '52...

what are people using for radiators? if the original were cleaned up, etc., would it even handle the job cooling an EFI 5.8? or am i forced to go aftermarket? (if the latter, best bets?)

thanks in advance.

 

I ran the original six cylinder application radiator in my 350 powered F4 and it cooled OK. Only problem I had was throwing water out at high speed. The 4PSI cap was not enough, IMO, so I went with a new radiator.

 

Would the old rad. handle the pressure with a higher psi cap? I heard they start springing leaks all over with a different cap.

 

I've seen arguments both way, yes and no. I was getting the truck ready for a trip to a TS event and did not want to find out that a higher pressure would not work somewhere along the road, several hundred miles from home.

 

Wise move. I think something 60 plus years old is doing good to hold the 4 psi let alone 14 or so. I have some confidence in it since it was reworked in 94 I think.

 

Howdy,

There's a couple of things you can do....

First, you'll want to run that engine at a higher temp than that old flat head ran. This would require a higher pressure cap and system pressure.

Those old engines and cooling systems used (I think) a 7psi cap.......... and with a more modern engine would "pop" using a 195 (or higher) deg thermostat.


Your EFI ECM will want to run at 195-220 so it might not give you the best economy with the engine running 20+ deg cooler. (or you may have to remap the ECM, buy a different EEPROM etc..etc)

You might consider an aftermarket aluminum rad for it if you don't want to do "stuff" to the ECM and you want to run a 15 psi (or higher) cap.

It's not the cooling capability of the older copper rad as much as it's the system pressure that you'll have at the higher temps.

I am using the original radiator for my F-600 and carbureted Y-block. I had my radiator rebuilt and the shop removed the 3-row core and replaced with a new 4-row core increasing the cooling by 25%. I also told the shop owner I wanted to run approx 20 hotter and he told me I be safe with a 13psi cap but no more.

Most newer EFI cars and trucks have 15/16psi caps and operate up to 230 deg.
(In general, the higher the temp, the more efficient the engine is anyway)

The rad shop told me that I shouldn't allow the pressure to exceed 13 psi or I would probably push the top or bottom tank right off the radiator.

I did a little searching around the internet and found a Dow Chemical engineering paper that has a chart for vapor pressure vs temp with different concentrations of AF.
http://msdssearch.dow.com/PublishedL...romPage=GetDoc

The above (TABLE-25 Propylene glycol) indicates that the pressure with a 50/50 mix at 200F will be around 10 PSI....... But remember, that temp is measured near the stat-housing or in the intake manifold. Temps will be higher in the heads and block.

Running 60% AF yields a slightly (a little less than 1psi) lower pressure and ethylene glycol is similar.

When I get mine together, I will have a gage on it so I can determine the pressure under load etc. My Y-block is carbed so I am not all that concerned with running it a little cooler, but I would like to start with a 190 deg stat.

I'm also going to use a (stock) clutch-type fan for a 429 but I don't know what temp it will engage. I may have to get a lower engaging clutch. I am also considering going to electric fans to have more control over when they come on. Flex-A-Lite has adjustable "fan-stats".


Regards,


Rick

 

You should check to see what temp thermostat Ford recommended for the 351W engine. A colder thermostat can cause plug fouling on newer engines. That said it is all a matter of degrees ( - pardon the pun). If you are not putting but a couple thousand miles on per year it may not matter that much.

Make sure that you check the depth of the radiator cap sealing surfaces in relation to each other. You can put a 14# cap on but if it doesn't seat against the lower surface it won't be holding 14# if anything at all.