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Hmm, that is the "short" radiator. Does your factory radiator support and shroud fit over it?
 
I will be making some blocks on the bottom, to lift it up high enough to fill the opening, and may need to mod the top plate also, haven't checked it yet. I won't be using a shroud, as I'll be using the Windstar fan setup.
Am I thinking wrong here?
 
I will be making some blocks on the bottom, to lift it up high enough to fill the opening, and may need to mod the top plate also, haven't checked it yet. I won't be using a shroud, as I'll be using the Windstar fan setup.
Am I thinking wrong here?

I have never seen anybody space the radiator up. Could work if you have the radiator support that bolts to the top of the core support.
There are basically two styles of radiator supports for 73 to 77 blazers/trucks.
The blazers/ trucks that came with 2 row(yes, there was such a thing MT/non AC used them. My 73 came with one.) and 3 row used a L shape support that bolted to the back of core support. These radiators are what I call the "short" style.


4 row radiators are taller and have wider tanks and used a support that bolts to the top of the core support. These are what I call the "tall" style.

When I ordered my 4 row eons ago, the guy had me measure my old (2 core) radiator which was short. I didn't know any better.
Even though I bought the 4 row isolators, the support would not bolt up because the wider tanks. Simple solution was to make some spacers between the radiator support and core support and zip tie the shroud to to crossmember. I used this same radiator and set up in my 74 and it still works.
 
that support I have on the frame in the pic is from a 79 C20...maybe the one in the K5 is the shorter setup. Time to take more junk apart and find out I guess. Once again the experiences of the brotherhood come through. Thanks JD, have you been running that 496 hard lately? Looks like a blast from the videos.
 
I wonder if it's shorter because the 81 and newer rad support is a bit lower than the 80 and older? Looks very nice, I'll likely go with the same rad when the time comes.

Sorry about your dog Jess!

rene
 
From what I have found, the radiators are probably the same size, the radiator supports up to 80 are the tall design, as evidenced by the higher profile hoods. The radiator securing top plate (does that describe it right) is different between the 80 and down, and 81 and up. This is the 77 K5 radiator support I will be using with the factory top plate that came with the truck. If you compare it to the 81+; this one has more of a drop to accomadate the taller height of the 80 and down support.

blazer027.jpg




The new Northern radiator compared to the old factory unit

blazer025.jpg




Will need to make a small mod to the support here. Everywhere else it fits without interference.

blazer026.jpg




The Windstar fans set on the radiator; Is this how everyone is mounting them? What did you do about the trans cooler lines? I think I will use an elbow coming out of the radiator and flex lines after that.

blazer028.jpg




The Iron Maiden is somewhat Nakid.
I'm happy with how solid this body is for being a MI truck...It has had a bunch of panels replaced with the cheap Chinawanese type metal, but its pretty solid underneath.

blazer031.jpg




Drivers side underbody looking from the firewall

blazer030.jpg




Pass side underbody

blazer029.jpg
 
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Having no inner rockers to trap salt and debris helps a lot in places that get winter. I did re-install inner rockers, but plan on adding some oversize drain holes so I can easily hose em out now and then.

Rene
 
for the record Dave..... on my 87 support, i have my rad blocked up 2"....
 
Having no inner rockers to trap salt and debris helps a lot in places that get winter. I did re-install inner rockers, but plan on adding some oversize drain holes so I can easily hose em out now and then.

Rene


NO doubt Rene, the salt likes to get into every crack and crevice imaginable. I hope to not expose it much to salt, but plan on cleaning up the underside (maybe sandblasting) and seam sealing, and painting. The truck has definitely had some floorboard issues, but the cab supports and structures are pretty solid still. They do show the surface rust on em, but hitting them with a pick hammer is pretty solid still.



Paul, so is the overall height of the radiator supports the same you think, and the top radiator reatiner plate the difference?
I was thinking that with the sheet metal change the radiator support got shorter also.
 
i really have no idea on the support.... i'll be kneedeep in that soon tho.... i have 2 at my disposal to do checks, 80ish and 87...

i didn't bother to figure that out when i did my install... gutted it, fit the new rad up, and it needed to go up.... obviously with the custom shroud/top plate, etc, my mounting is very different....
 
From what I have found, the radiators are probably the same size, the radiator supports up to 80 are the tall design, as evidenced by the higher profile hoods. The radiator securing top plate (does that describe it right) is different between the 80 and down, and 81 and up. This is the 77 K5 radiator support I will be using with the factory top plate that came with the truck. If you compare it to the 81+; this one has more of a drop to accomadate the taller height of the 80 and down support.

blazer027.jpg
That is the short style radiator top plate. Looks like the radiator fit nice with it.

As for what size radiators fit what years, to me the short style seems to to the same from 1967 to 88. It just the first Gen blazer have a curved outlet. I can't say for sure.
Now trucks 73 to 80 with the "tall" 4 core have a plate that mount to the top of the core support.
I think 81 four cores are the same size as the "short" radiators however the diesels have a wider radiator. Not to sure, I have to compare I diesel radiator I have with the one in my blazer.

As my blazer, it is in pieces. More on that later. I have to go.
 
I can post up a diesel radiator/top plate tomorrow for some comparison also.
 
this is the diesel radiator with shroud/top plate combo...

HPIM2173.jpg
 
Well, that blew my theory out of the water. The diesel radiator looks like the tall style, and since it wider, it extend past the top radiator mount.
 
Been trying to get more motivation to get back into this heavily. One thing I think might help is to have a check list of things to work on and an order with which to do them.

If you see something you think might be in a better place please comment.
If you see something missing please comment.

This is what I've come up with off the top of my head:


IRON MAIDEN TASK COMPLETION LIST



Break in engine……call Jerry Arnold for spring change

Make transfer case cradle, Check t/c output angle

Weld rear axle tubes

Mount rear axle truss

Check and modify rear pinion angle

Mount anti wrap kit to axle/frame

Route exhaust system

Fab and mount midframe skid plate

Fabricate front axle truss

Check front axle pinion angle

Figure suspension travel

Check front shackle angle

Figure shock mounting

Figure bumpstops and travel limiters

Weld on roll cage tie in plates

Figure Rock rails mounting points

Modify frame rail @ rear fuel line

Mount fuel filter @ tank

Fab and mount for fuel tank skid plate

Figure routing for PS hoses/ Make hoses

Route Hydroboost lines

Route and fabricate brakelines/proportioning valve

Remount rear brake calipers for proper positioning

Fabricate battery mount

Figure battery cable layout, and run conduit

Figure trans cooler mounting

Fabricate trans cooler lines

Figure trans temp guage placement and needs

Mount front winch bumper

Mount 9.5XP winch

Figure winch cable routing

Install battery master shutoff

Install remote starter solenoid

Run Battery cables

Clean and zinc coat inside of frame rails

Weld up frame boxing kit

Fab rear recovery points

Fab and install tie down tabs

Weld on Spring limiting block mounts (for trailering to limit suspension travel)

Fab and install axle venting system






Dis-assemble Drivetrain and frame



Sandblast and paint frame

Dis-assemble the 205 for replacement of the front output, add a spacer,
replace the shifter rails w/ ORD rails for triple stick, drill and tap for a sightglass oil level tube.

Drill and tap for 203 sightglass oil level tube

Locktite everything doubler related.

Fab and install transfer case venting system

Paint rear axle/springs/all brackets/shackles etc

TH400, install trans temp sender unit.





Begin final (?) assembly


Cage and body



Floor mods for raised fuel tank

Seating

Rock sliders

Boat side

Cage installation

Battery mount

Fab a mount for Hi-Lift

Fab a mount for fire extinguishers

Fab mounts for coolers, spareparts, and toolbox.
 
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I realize I am a little late to the party, but I wanted to try to help out on the radiator information before it was real old news.

As for what size radiators fit what years, to me the short style seems to to the same from 1967 to 88. It just the first Gen blazer have a curved outlet. I can't say for sure.

Basically true. The first gens were in fact the only ones to get the curved outlet. There were some minor differences along the way (mainly thickness), but the one thing that did stay the same through the years was the height. A short rad was the same height across the board. GM never put a tall rad in a first gen. It will fit, but it is a full custom job.

Now trucks 73 to 80 with the "tall" 4 core have a plate that mount to the top of the core support.
I think 81 four cores are the same size as the "short" radiators however the diesels have a wider radiator. Not to sure, I have to compare I diesel radiator I have with the one in my blazer.

Yes, 73-80 trucks used that plate type upper mounting for the tall radiators. The '81 and newer four row rads are the same as the early ones (industry number 730), the diesel/later BBC radiator being the same height, but a few inches wider. From 73-80 versus the 81 up, the only difference is the upper mounting setup. Instead of the plate, they used two individual bolt-on upper brackets that held the radiator bushings. Now, some other things changed in that timeframe. From '81 on, HDC on a small block no longer got you a four row rad like it did in earlier years. It now got you a tall three row. The short three row was still used after '81, but it no longer had an upper mounting plate. The upper mounting plate function was now handled by the shroud which had the "plate function" built into it. A tall four row radiator can be a bolt-in deal for a '81 up small block truck. You need the tall four row rad, the upper mounting brackets for a BBC/6.2L and a fan shroud from a 73-80 w/HDC and A/C.

this is the diesel radiator with shroud/top plate combo...

HPIM2173.jpg

Part of the reason this looks wrong is because the upper shroud is '81up and it is shown on an '80 down core support. This setup is one that I had thought about, but never actually tried. It is hard to tell from the pics, but it looks like the upper mounting brackets are not there. This radiator was not invented until the later '81 up core support, so mounting it in an '80 down would require some engineering especially in the shroud dept to make it look decent.The pinchweld at the top of the core support changed--on the 73-80, it was a very flat-top core support whereas the '81 up had a "ridge" at the back of the top of the core support. I have seen some pretty hack jobs of making the early plate work on the later core supports, but it really isn't too right.

I hope this helps as, generally speaking, most of the rads are the same for a given height, just different mounting early to late.

Last note for future builders: the tall four row radiators are available in aluminum (two 1' rows instead of four) in AC Delco 20978 (or equivalent). I recently purchased one in a industry number 730 box and it had a Delco/Harrison rad in the box with all of the GM markings ground off of it. I think it was under $200.00. Just some food for thought.
 
And i thought i had a long list... Really like your build by the way:waytogo:

I'm sure it will grow by leaps and bounds, that is just what came to mind....thanks for the comps.:waytogo:


NICK....thanks for the input. :bow:

As you pointed out my supports are pre 81, and that diesel radiator came out of an 82 with all the brackets and shrouds with it from the same vehicle. I didn't get the support as I thought it would be a shorter profile than my 77 would fit. And I do recall my 85 having the two separate brackets for locating/securing the top of the radiator as you metioned.
I was going to make this one work, and it probably would have, but Aluminum seems to be the way to go for my application. I sure don't want to have to stop whatever I may be doing because of fear of overheating, hence the use of the Windstar fans too.
 

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