I am installing a 400 small block in a truck which formerly had a 6 stock. Unlike the previous/recent post I want to reuse the stock tanks and radiator location but am not sure.

The facts are this - the stock radaitor is 18x20 with a 3 inch core. The radiator the 400 used to live on was 18x28 with an integral transmision cooler.

So I was thinking that even though the stock radiator has 1/3 less surface area [but is 1/3 thicker] if I recore the unit with new high efficiency core and separate the transmission cooler it should be up to the task???

Is this a route that others have used successfully - or is a custom made aluminum the only option???

I was hoping to use the factory fan from the 400 (its a 7 blade) but wont know until the next few days if I have the room.

I'd appreciate all advice... Its always a waste to waste.