Who's running a stock 3 Core Radiator with a Big Block?

[Yamariv]

Been reading a lot about Big Block conversions and I've seen some posts where guys are running a 3 Core rad with a big block. Is this doable realistically or is a 4 Core a must?

Did GM always put a 4 Core as standard for Big Block trucks?

[jimijam00]

There is no such thing as a three or four core radiator.

I run a two row radiator and it cools just fine in 100f summer temps.

[Yamariv]

[QUOTE=jimijam00;9197963]There is no such thing as a three or four core radiator.

I run a two row radiator and it cools just fine in 100f summer temps.[/

Is your radiator a stock style 2 core or are you talking a larger tubed aluminum one?

[kwmech]

Have a 68 with a factory big block. Originally a 396 and now a 454. The 396 came with a 3 core rad...no A/C. I put the 454 in and instantly had heating issues. I converted to a 4 core. Problem went away

[jimijam00]

Originally Posted by Yamariv

Is your radiator a stock style 2 core or are you talking a larger tubed aluminum one?

It's a larger tubed two row aluminum aftermarket radiator.

[Yamariv]

Originally Posted by kwmech

Have a 68 with a factory big block. Originally a 396 and now a 454. The 396 came with a 3 core rad...no A/C. I put the 454 in and instantly had heating issues. I converted to a 4 core. Problem went away

Did the 3 core run ok with the 396?

[kwmech]

Yes it did, never had a problem, but the added cubes with a more than stock cam and compression pushed the limits on it at idle. Driving down the road was not a problem

[Yamariv]

Originally Posted by kwmech

Yes it did, never had a problem, but the added cubes with a more than stock cam and compression pushed the limits on it at idle. Driving down the road was not a problem

Ok, that's good to know thanks! I'm thinking of sticking around the 400 cube big block so maybe my 3 Core rad will work!

Do you know if your 3 core came from the factory? I always heard GM would do the 4 core standard with all big blocks? Or maybe only if they had AC..my truck won't have AC.

[kwmech]

Came stock with the 3 core. I am the 3rd owner and was able to talk to the original owner who is local. The 2nd owner did not drive the truck much. Truck has only has 150,000 original miles on it, but it sat for awhile which sometimes does more harm than good.

[Yamariv]

Originally Posted by kwmech

Came stock with the 3 core. I am the 3rd owner and was able to talk to the original owner who is local. The 2nd owner did not drive the truck much. Truck has only has 150,000 original miles on it, but it sat for awhile which sometimes does more harm than good.

Great info, thank you! Yeah, my theory is that the 402's without AC came with a 3 Core and the ones with AC GM sent out with the 4's.

[Steeveedee]

I saw a post somewhere but doggoned if I can find it, now. It detailed things like this, for all the options. It's where I discovered that my truck (BBC w/AC) should have had a 19" fan. When I got into solving the running hot issue, I replaced the original fan, which was 18", with a 19" fan. I did not know about this information at that time.

[Already Gone]

My first truck a 1972 C10 came with the stock 350 engine and auto trans from factory and when I bought it it had a 396 in it. I can't say for sure but am pretty sure it had the stock 3 row rad that came with the truck and I never had a heating/cooling issue in the 13 years I owned it. I think if you use a 3 row factory rad with a BB that's not to exotic you will be fine. My present 72 C10 with factory A/C had a 3 row rad from factory and it had never been touched and I have done a few 4/5 hour drives in 27/28C ( 80 F ) with the A/C on, original style compressor although rebuilt, and never had an over heating issue.

[Steeveedee]

^That kid is digging your under hood art!

[Joyridin]

I had a 3 row with a 454 no A/C. The radiator was a new copper/brass style. It did not like hot days. I changed to a wide 2 row aluminum and it worked better.

If you are going BBC with A/C, I would use a 4 row copper/brass, or find a really wide aluminum version.

[steveo70]

[quote=Yamariv;9197964]

Originally Posted by jimijam00

There is no such thing as a three or four core radiator.

I run a two row radiator and it cools just fine in 100f summer temps.[/

Is your radiator a stock style 2 core or are you talking a larger tubed aluminum one?

I us a new larger tubed 2 row aluminum, a GM 7 blade fan and a heavy duty clutch fan. zero issues. .030 454 mild hyd roller build.

[Speedracer39]

I have a 496 with an original 3 core and a clutch fan no A/C drove to c10 nationals in Tx from Nebraska no issues. I am currently adding vintage air and plan on going with alum radiator and electric fans.
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[Yamariv]

Thanks for all the replies guys! Looks like my Big Block dreams have been dashed as I thought my 3 OTT Saginaw was the base tranny for a BB but it turns out its an HD version. Plans have changed to sticking with a future small block upgrade now. My current 3 core should have no issue with a nice little 350

[Already Gone]

Originally Posted by Steeveedee

^That kid is digging your under hood art!

Yea, that was on the truck when I bought it and I wasn't a fan of it and was gonna have it removed but yes, people especially kids liked to look at it so i left it.

[mr.mud1]

my 72 402 California truck with A/C,all factory,came with a 3 core rad but rubber saddles and tanks that would accomodate a 4 core.i built myself a new rad,installing a new 3 row core,just like it was,could have ordered a 4 row but i thought if it lived in California with a camper on it's back,it would do fine here and it does.

[Yamariv]

Originally Posted by mr.mud1

my 72 402 California truck with A/C,all factory,came with a 3 core rad but rubber saddles and tanks that would accomodate a 4 core.i built myself a new rad,installing a new 3 row core,just like it was,could have ordered a 4 row but i thought if it lived in California with a camper on it's back,it would do fine here and it does.

Wow, very interesting!! If it had all the 4 core mounts is it possible it was switched out for a 3 core earlier in its life?

[Steeveedee]

Pretty sure the tanks are the same, for 3 and 4 row.

[Ironangel]

I ran a 3 row with the 396 I had, I ran a 7 blade fan and shroud and it kept the 396 cool. I swapped it out for a 4 row when I dropped the 427 in it. The 427 is 12.5:1 CR and 110 race fuel, it runs quite a bit hotter so I cool it with dual electric fans and HF water pump. The 3 row will cool a big block if it's non-AC and has good flow. I ran a 180 thermostat in the 396, never had any problems...

[mr.mud1]

Originally Posted by Yamariv

Wow, very interesting!! If it had all the 4 core mounts is it possible it was switched out for a 3 core earlier in its life?

hi.my rad was never changed.Steeveedee is correct.there may be a 3 row only set of tanks but i doubt it.the tanks on my truck will accomodate a 3 row or 4 and the mount saddles are big enough for a 4 row.you can see on flange on my old original core,where it solders it in the tanks,a flat place along that flange to fill up the tank and where it would've been punched for 4 rows,if need be

[Already Gone]

My 72 with Factory A/C and 350 had the same as Gregs 4 row tanks and mounts and a 3 row rad. Greg is more skilled than I am as I took mine to a rad shop and they made me a new 4 row rad and put the original tanks back on and am reusing the mounts too. Its installed in the truck now but I haven't ran it yet as just finishing engine swap. I also pulled my heater core, glad I did and a bonus got the crud out of the heater core box, and had it recored as figured it'd be the weak link in the all new system.