radiator question

[dubie]

with switching from an inline to a 350, do I need to change my rad? It has the stock 2 or 3 core in it. It doesn't get deathy hot up here like it does in some parts, plus I will be installing an electric fan set up. So do I need a 4 core? ALso, are the hose diameters different from the 2 core to a 4 core?

[bpmcgee]

Dubie,

My '71 blazer with a 350, manual, and no a/c would have come from the factory with a 2 core. Auto trans or A/C would have been a 3 core, and BOTH would have been a 4 core.

And no, the hoses are identical.

Brian

[CPNE]

No problem with the 2 core. If you opt for a 3 or 4 core, then you need to change the top and bottom mounting pads and brackets.

[Sweet72]

I don't mean to steal your thread dubie, but are there only two sizes of rad mount brackets/pads? My truck has a two core (not sure if it's had a new core soldered in) and the new pads I bought for the 2 core are too small, tanks won't fit inside the pad saddles! ???? thanks fellas

[CPNE]

There is one problem I can think of when using the I6/manual radiator with a V8. The problem is not cooling capacity (in your climate) but the width of the radiator itself. If it's the stock I6/manual radiator, it is not as wide as the V8 or I6/auto radiator. Consequently the hold down brackets are not spaced as far apart as on a v8 (notice the 2 sets of mounting holes on your rad support). If you go with what you have (again assuming its the stock I6 unit), you won't be able to bolt on the V8 fan shroud without some "backyard engineering".
I guess I vote on getting the right radiator for the application now, while you have it all apart.

As for the other qestion, there may be a difference in radiator core width between the 3 spplications - I6, V8 manual/no A/C (2 or 3 core), and the 4 core unit installed in V8/A/C/auto rigs.

[dubie]

Thats the reason I am going with an electric fan Jeff But I'm glad you brought that up. good point!!

[CPNE]

Originally posted by dubie
Thats the reason I am going with an electric fan Jeff But I'm glad you brought that up. good point!!

Now you have to upgrade your electrical. (Oh what a tangled web we weave...:p )

My I6 to smallblock with 3 speed manual project just fell together almost like it was designed that way, what's your problem?

[dubie]

yeah, I will have to do some more wiring I am going to stick with the clutch fan until the break in is done, but after that it's getting the 14" electric fan. I have heard that a Van shroud or a big block shroud would work for my application. Maybe I'll just do that and leave it......................who knows with this project anymore

[Longhorn Man]

Tim, your engein is in the inline position, right?
With the exceoption of what was said about the width, there are a couple solutions for the fan shroud.
Crazy longhorn (anyone know where he's been??) said that you can get a long water pump, and that should place the fan pretty much right in the correct spot of the stock 2 wheel drive small block shroud.
There is also the 'stock' way to do it, even with teh inline positioning, you can just get a small block 4X4 shroud. Since the 4X4 placed all engines back there, the fan will fit just like 'stock' with the 67 - 72 style short water pump.
Personally, i would go one of those routes, and then have the electric fan as a back up or aux fan...that's mostly becouse I don't trust the electric ones...I've seen WAY too many cars that came with them blow head gaskets becouse the fan died and the driver had no idea.

[dubie]

Thanks for the tips Andy. My engine is from an 82 and came with the 9" long water pump, so the stock clutch fan does sit forward quite a bit. I am going to do the break in with the clutch fan and may end up staying with it just so I don't have to mess with more wiring. I just wanna get it done and running right now

[gr8scott51]

My 350 is in the I6 position with a long waterpump and small block shroud. I added a 4 inch wide strip of aluminum to the shroud lip to fully enclose the blades. Oh yeah, I put in a 4 core radiator because it overheated so bad during the cam break in, but I think the stock one would have been fine after that.

[Lobo'74]

I had a new (one year old) I6 size radiator in my hopped up 350 Truck. Always ran HOT. Was about 210 or so at stop lights. In haevy traffic got so hot I had to shut it off. Bought a 4 core HD (V8) radiator off of E-bay. Put it on and a shroud and once the thermostat opens up Truck runs 190 (late summer/early fall) to 160 (winter). Only problem with my cooling system now is the fan blade sit about an inch or two away from the shroud. I think I need a longer nose on the water pump. The one on there now is a short one.

I'll be getting rid of my "new" old I6 radiator on the parts board in the next week or so.

[67Fleetsidedream]

Get a 3 or 4 core radiator. There is probably years and years worth crap in the inline 6 radiator. And I agree it will always run hot with the I6 radiator.

[Tx Firefighter]

Mine always ran right at 180 degrees with a 6 cylinder radiator and a small block with no fan shroud at all, except that little 6 cylinder sheetmetal piece on top. This is 3.73 gears and running it hard in Texas heat.

Look at it this way, if it works, you've saved money, if it overheats, then you can drop the cash on a bigger unit.

[slam33]

I would just go to a 4 core, I got one from US Rad for $125 and they brought it to me. I got the mounts and pads from LMC. The thing runs cool as can be.

[Andy4639]

The radiator is good insurance for the motor to run cool. The clamps are different for the 4 core. I just had mine cleaned and fixed where it was leaking on the inlet nozzel.
The shroud should help a lot on the cold air flowing through the fins to keep the air directed to the motor.
The blades shouldn't be all the way in the shroud. The best position is about 3/4 of it inside the shroud. This is for maz cooling effect.