Can someone teach me about radiators and what will fit?

[Lgarretto]

Howdy guys. Bought an 89 swb about a month ago. Been fixing it up. 350 with a 5 speed. Runs fine but wants to overheat. Atelasdy it gets pretty warm. Reads 230 or so. I replaced the thermostat with a 160 version. So I am pretty sure I need a radiator. I will need a better one eventually anyway, I don't plan to leave the engine stock in any sense.
Could someone give me an idea on who sells a good 3 or 4 core radiator for not too much dough? One that would fit of course.
I appreciate it.

 

[Jglew82]

Have you checked the temperature at the radiator inlet with a temp probe? Bad temp sender can read high when they go bad (mine did). Also make sure the fins aren't blocked and the fan clutch is operating properly. Standard 28" or 34" OE style radiator will cool a 350 perfectly fine. Mine has an iron block 6.0, and the stock 28" radiator cools it perfectly fine in rush hour in the Texas heat.

 

[Erik the Awful]

There's been a fair amount of discussion on radiators lately. Back in the day 3 or 4 row radiators were the best way to keep a monster engine cool, but that was a limitation of the malleability of copper. Aluminum radiators can be more efficient with fewer rows. Buy a good aluminum radiator and you'll be okay. Pay attention to radiator width when you buy. V6s had a narrow radiator, V8s had a mid-sized radiator, and Suburbans had a wide radiator. You can step up to a Suburban radiator, but you'll need the shroud and I think there's a bit of sheetmetal work to do.

Ditch that 160* thermostat and get a proper 180*. Once the thermostat is open, it does nothing more to cool the engine. A 160* just opens earlier, and in cool weather it can allow your engine to run too cool.

 

[PlayingWithTBI]

Put a scanner on it and see if the CTS that feeds the ECM reads the same too.

Do a compression and leak down test to ensure you don't have other underlying issues like a blown head gasket. Mine was running hot and would get up to ~230* at idle. Compression test only showed a 5psi difference on the 2 cylinders that had signs of blown passages to the neighboring cylinders. I was losing about a 1/2 gallon of coolant in a week, no white smoke, no sweet smell, no water in oil or oil in water.

 

[Lgarretto]

Yeah. Fan clutch works. And the temp gauge is at lest semi accurate. At least, when I put the 160 degree in it read about 170 ish till I went on a longer drive on the highway (going over 45-55). I need to actually check it with a thermometer.
Either way though Im just not sure that radiator will cool the engine I'm putting in the truck anyway.

 

[Lgarretto]

Also I don't think I have a blown head gasket. I haven't done a compression test but there's no froth. No milky oil. I probably need a new radiator cap at the very least. It blows coolant out of the cap pin every time I drive the truck

 

[PlayingWithTBI]

I haven't done a compression test but there's no froth. No milky oil

I didn't have any of that either but my head gaskets were blown.

 

[Lgarretto]

Hm. I will check that then. It doesn't read hot at idle. Or driving around town though. Just highway when I am actually spinning the engine a bit. Not that it spins much with 3.09 gears.
Having said that do yall think a 2 core aluminum rad would cool a 383?

 

[PlayingWithTBI]

I bought this radiator, it's thicker than the OE one so I had to trim the sides of the shroud to fit. It's advertised as 800HP. It looks like they're out of stock right now and will ship in October.
https://www.radiatorexpress.com/Product/222481/1031106#vehiclefitmenttab

 

[PlayingWithTBI]

Here's what I did to the shroud. I slit some fuel line to seal/protect against the radiator.

You must be registered for see images attach