47-55.1 GMC radiator in Chevy radiator support for extra room

[mr48chev]

I decided to do a separate thread on this in case someone is doing a search on the subject.

This is my KKS aluminum radiator sitting in a slightly hacked (that needs some finishing to be right) Chevy radiator support.

I knew that the GMC radiator gave some extra clearance but wasn't positive on how much but here are the photos.

The core support that I used is one that I have had for 30 or so years that came off a donor truck and was already hacked up. One can't run the X brace but half of them are hacked out from the get go and I plan to run an AC condenser with it and may fab a stronger cross brace out in front for it that is attached to the support.

The bottom front corners of the support have to be reworked a tad for clearance that is probably torch and ball pein hammer work

As far as that particular radiator goes it is priced not much more than a Champion, the tig welding is really nice and it looks well put together eBay item number:225850522950

[leegreen]

that looks like it worked well.

I did something similar but with chev rad support and radiator tipped forward a the bottom. I used short pieces of angle iron to space the cross brace out, it worked out quite strong. I think those cross braces are pretty critical. not sure you can make out the angle here, but it does not show up at all in any of the post paint pictures I have

[leegreen]

Are you running the original 292 damper pulley?

I collected a couple 292s and plan to swap out my 250, maybe next winter. Both 292 dampers are quite long, but will probably just fit behind the rad with my setup.
They both show some signs of the rubber protruding which is a little concerning.

I could swap to the 250 damper with the added and significant advantage that my other pulleys and brackets all line up, but I understand the 292 benefits from the heavier damper. The author of the book on hotrodding these engines said stick with the larger damper, but it also looks like the last couple years of 292 equipped G-vans used the shorter 250 style. And I have no plans to add power mods.

[mr48chev]

The intent is to stay with the 292 damper and pulleys but Bridges get crossed one by one when we get to them.

We had been taking radiators in the other thread and I just decided to go out and dig mine out of the shed and see how it all fit up this morning. That gives me an idea of what other mods I have to make to the radiator support to safely mount the radiator and not have rub spots on the tanks That includes grinding the rather ragged cut line at the top of the bracket and creating a bit of room for the front bottom corners of the radiator on the front side of the support. I may have to use some one inch flat bar for spacers to get a tad bit of top tank space.

Since the stretch cab project has GMC frame I have thought about using a GMC radiator support and swapping the top brackets of that Chevy radiator support over to it or doing a cut and weld thing on the sides to have GMC on the Bottom and Chevy on the top.

In other news, I need to find out from Martin how much space he has left between the top of the radiator and the hood after he did the section.

[JDarby]

Did all these radiators come with an X brace from the factory?

[mr48chev]

Originally Posted by JDarby

Did all these radiators come with an X brace from the factory?

That I am not sure of. Too many of them had the X cut out along with the cross piece at the top to facilitate pulling the engine. I've had several core supports that had been torched off rather crudely when an engine was pulled and most of those came in a truck with the engine block in it when I got it.

The X may have been added in 49 or later too as several changes were made in 49 and the radiator supports that I have with an X are 49 or later. 47/48 had two bolts or a U bolt in the center while 49 and later had the two bolts out to the sides.