[JC455]

Ok, so Ccass said in another thread that Max Perf. was looking into a kit to modify the Non-A/C support so it would house the larger (17-1/2" core) radiator.
This sounds like a GREAT idea to me! I have a 64 Tempest 6 that is about to get a Pontiac V8 injection-- I 'KNOW' I'm gonna need a big radiator to cool the eventual 400 stroker that'll end up in it. Since I'm gonna be doing it, might as well do it right the first time...
So, with that being said, anyone ever modified a 15-1/2" support? It seems like you could cut the bottom section of the support out, make some extension straps (probably 6" - 8"), and either bolt, rivet, or weld them to the upper and lower parts with the 2" gap being provided by the extension pieces.
Am I missing anything? Is there a huge difference in how the big radiator is mounted vs. the smaller one? Can ou use the smaller mounting brackets on the bigger core?
Thanks!

[64speed]

I didn't know there was a size difference till I ordered my radiator. The 17 inch bolted right in the hood just wouldn't close. I saw what you were talking about modifying the saddle to take a 17 inch core but in a private message ccass told me to order a 66-67 radiator and appropriate hoses and waterneck and other than it not being correct it will cool just fine. They also assure me that the 15 inch non ac radiator for the 64 is more than adequate. The 66-67 is just overkill.

[64speed]

My 64 radiator upper hose is on the drivers side. Am I missing something?

[b-man]

'64 & '65 V8 radiators all have the upper inlet on the passenger side.

'66 & '67 radiators have it on the driver's side.

The later design radiator is a direct bolt-in on earlier cars, other than having to notch the fan shroud for the new inlet location.
------------------------------------------------
Sorry I have nothing to offer on modding the standard radiator support to fit the taller radiator.

But I can tell you that the A/C support sits pretty much even with the bottom of the bumper so there really isn't any room to spare. Scraping the bottom of the bumper isn't all that hard to do once or twice and if you do that once with a modded support that hangs below the bumper you'll be in for a big disappointment.

[64speed]

I had a tripower setup on my warn out 326 when I got it and I took it off and put the two Darrel intake on it. When I ordered my champion I just used the thermostat housing that was on it and used the tripower hose. I guess I got a funky setup

[mrgto69]

The 64 rad support is already at it's biggest... meaning there is only 1 size radiator for non AC & AC. In 65 Pontiac changed to two different sizes. That followed suit in 66-67 also. We have a 66 non AC & AC rad support here and they are quite different. Yes we are thinking of making an adapter that you would have to "splice-in" to a non AC support. Check out the pictures I have attached of the differences. The AC is on the right.

[b-man]

Originally Posted by mrgto69

The 64 rad support is already at it's biggest... meaning there is only 1 size radiator for non AC & AC. In 65 Pontiac changed to two different sizes. That followed suit in 66-67 also. We have a 66 non AC & AC rad support here and they are quite different. Yes we are thinking of making an adapter that you would have to "splice-in" to a non AC support. Check out the pictures I have attached of the differences. The AC is on the right.

This information regarding the 1964 radiators and core supports is incorrect. The 1964 factory A/C cars used a different core support (17-1/2" core height) than standard non-A/C V8 and six-cylinder cars (15-1/2" core). Below are pictures of my personal 1964 cars and parts.

1964 A/C core support. This car started life as a 6-cylinder car, I replaced the original 15-1/2" support with a GTO or A/C car 17-1/2" support during a 455 V8 engine swap.



Another 1964 A/C support, as you can see this car is equipped with factory A/C.



1964 non-A/C V8 and six-cylinder.



1964 non-A/C support with six-cylinder radiator and sheetmetal baffle used for the narrower six-cylinder radiator. This is the radiator and core support that I removed from my 6-cylinder Tempest.

[b-man]

Again, if you're going to modify your non-A/C support it's not as simple as extending the bottom downward by 2".

If you do that the bottom of the modified support will now extend 2" below the bumper, sacrificing much-needed ground clearance and looking rather ugly too.

The bottom of the factory A/C support is essentially flat with the radiator resting on some small rubber insulated brackets that are welded to the flat floor of the support.

[JC455]

Originally Posted by b-man

Again, if you're going to modify your non-A/C support it's not as simple as extending the bottom downward by 2".

If you do that the bottom of the modified support will now extend 2" below the bumper, sacrificing much-needed ground clearance and looking rather ugly too.

The bottom of the factory A/C support is essentially flat with the radiator resting on some small rubber insulated brackets that are welded to the flat floor of the support.

Bart-
Thank you for posting this- it is VERY enlightening!

[Ccass]

Originally Posted by b-man

The 1964 factory A/C cars used a different core support (17-1/2" core height) than standard non-A/CV8 and six-cylinder cars (15-1/2" core).

B, I'm going to have to ask that we hear from more 1964 owners on this. For 30 years, we here at PY have operated under the assumption that all 1064 GTO's had AC height radiator supports. And in that 30 years, I can't remember getting a radiator returned for the radiator being too tall unless the owner originally had a 6 cylinder car. We're even fairly confident that even 326 cars had the taller radiator support. This goes for 1964 only.

So I can certainly see by your cars that the shorter support was used on a 6 cylinder but I'd like to hear from other 1964 owners that have original v8 cars....Tempest, LeMans and GTO owners alike.

[Ccass]

So to specifically cover the conversion topic, B-Man brought up a good point. By just lowering the non AC lower brace by 2", the brace will protrude below the bumper and probably won't look good.

Our plan would be to duplicate the bottom of the AC support.
Here's the simplest of instructions.
1. Cut your non AC support just below where the main upper part of the support ends.
2. insert our new AC bottom brace conversion.
3. Weld or bolt to the existing non ac support.

The new conversion will not hang down any lower than factory and it will be very difficult to see that a conversion has been made even upon close inspection.

[JC455]

Originally Posted by Ccass

So to specifically cover the conversion topic, B-Man brought up a good point. By just lowering the non AC lower brace by 2", the brace will protrude below the bumper and probably won't look good.

Our plan would be to duplicate the bottom of the AC support.
Here's the simplest of instructions.
1. Cut your non AC support just below where the main upper part of the support ends.
2. insert our new AC bottom brace conversion.
3. Weld or bolt to the existing non ac support.

The new conversion will not hang down any lower than factory and it will be very difficult to see that a conversion has been made even upon close inspection.

This sounds like a great idea.
As I was looking at Bart's pics, I noticed the hood latch support bolted to the bottom of the core support-- Are your conversion brackets going to have all the holes for the support bracket, radiator mount holes, etc.?
Thanks!

[AdamIsAdam]

Subscribed. This sounds interesting.

As for me, my car was originally a 6 and I have the 15" rad support (and aftermarket radiator for that matter). So I'm probably not much help. Just interested in the outcome of this conversation about 64's.

[b-man]

Originally Posted by Ccass

B, I'm going to have to ask that we hear from more 1964 owners on this. For 30 years, we here at PY have operated under the assumption that all 1064 GTO's had AC height radiator supports. And in that 30 years, I can't remember getting a radiator returned for the radiator being too tall unless the owner originally had a 6 cylinder car. We're even fairly confident that even 326 cars had the taller radiator support. This goes for 1964 only.

So I can certainly see by your cars that the shorter support was used on a 6 cylinder but I'd like to hear from other 1964 owners that have original v8 cars....Tempest, LeMans and GTO owners alike.

Hi Chris,

I'm afraid your assumption that all 1964 V8 cars used the tall 17-1/2" core and the flat-bottom GTO or A/C support is incorrect.

My old '64 GTO clone (shown below) started life as a 326 car and it had the smaller standard V8/6-cylinder core support. By the time I first acquired that car it had been modified for street racing and didn't have a 326 in it, it had a '69 RAIII 400 engine.

However it did have all the signs of being an original 326 car. You could see where the 2 emblem holes for the '326' fender badges had been filled in each fender and the clincher being the fuel line running down the driver's side of the frame. All 6-cylinders cars as we all know have the fuel line on the passenger side.

Also while hunting parts about 20 years ago in our local Pick-Your-Part yard I came upon a '64 LeMans 326 car that was still mostly complete. I pulled the front bumper and brackets, the hood, core support, inner fenders, instrument cluster, tail lights, valley pan, exhaust manifolds and the non-power steering alternator bracket assembly.

The core support (standard V8, 15-1/2" core) clearly had never been removed from that car and the 326 engine was essentially untouched as well. The core support was a bit rotten near the frame mounts and after keeping it in my '64 parts stash for many years I gave it to the scrap man a couple of years ago because it wouldn't have been worth the trouble to repair the rust.

A couple of my friends were both '64 fanatics and coming up with a GTO radiator support was rare. If the GTO-style supports were as common as you think we'd have had plenty of them, but they were quite hard to come by. The GTO support that I have in my white Tempest was a damaged unit that I had professionally straightened, the one in my Le Mans convertible is the factory original since it's an A/C car.

Think about one thing - why would GM use a core support for the 6-cylinder cars that requires a sheetmetal filler piece, so air doesn't bypass the narrow radiator that sits in a wider opening?

The logical answer is because GM is very cost-conscious and designed that support as a dual-purpose part. It can be used for the non-A/C 326 cars as well as for the standard 6-cylinder cars by simply using that sheetmetal baffle when installing the narrower radiator. GM wouldn't have designed that core support solely for 6-cylinder use unless it fit the 6-cylinder radiator without the need of the baffle plate.

Bart

[Lemans64]

I have 2 rad supports and both v8 cars, both are the non a/c style. Still have original from my car, just rusted a bit so found another. did not know of the a/c support or would have looked for one of those. 2 inches make a big difference according to my wife, LOL.

[Tom Vaught]

Originally Posted by Ccass

B, I'm going to have to ask that we hear from more 1964 owners on this. For 30 years, we here at PY have operated under the assumption that all 1064 GTO's had AC height radiator supports. And in that 30 years, I can't remember getting a radiator returned for the radiator being too tall unless the owner originally had a 6 cylinder car. We're even fairly confident that even 326 cars had the taller radiator support. This goes for 1964 only.

So I can certainly see by your cars that the shorter support was used on a 6 cylinder but I'd like to hear from other 1964 owners that have original v8 cars....Tempest, LeMans and GTO owners alike.

Bart Is Correct!

Two Totally different Horse Collars for the same 64/65 GTO Vehicles.

As Bart had posted the 17" radiator WILL NOT fit into the 15-1/2" core support height envelope. The upper tank position will Not allow the hood to close.

I have taken 15-1/2 Three core Radiators and added Higher Fin Count parts and an extra core but the height size locked in that dimension.

Not all 64 GTOs got the 17" core support, My car was a April Built car and as John V can explain was built with the 15-1/2" radiator horse collar parts FACTORY.

Early in the year the "Only 17" radiator parts were used. Later production cars got both.

So it is some effort to actually add the 17" core support to the 64 GTO.

You can mod the 15-1/2" core support so that the flat bottom parts are there but it is a bunch of work according to Scott Tiemann.

So your assumption here was based in early info from literature and does not reflect actual production.

Tom V.

[Ccass]

Originally Posted by Tom Vaught

Bart Is Correct!

Two Totally different Horse Collars for the same 64/65 GTO Vehicles.

As Bart had posted the 17" radiator WILL NOT fit into the 15-1/2" core support height envelope. The upper tank position will Not allow the hood to close.

I have taken 15-1/2 Three core Radiators and added Higher Fin Count parts and an extra core but the height size locked in that dimension.

Not all 64 GTOs got the 17" core support, My car was a April Built car and as John V can explain was built with the 15-1/2" radiator horse collar parts FACTORY.

Early in the year the "Only 17" radiator parts were used. Later production cars got both.

So it is some effort to actually add the 17" core support to the 64 GTO.

You can mod the 15-1/2" core support so that the flat bottom parts are there but it is a bunch of work according to Scott Tiemann.

So your assumption here was based in early info from literature and does not reflect actual production.

Tom V.

While I think we're all in agreement that the 17" radiator will not fit the non ac radiator support........Wow, 30 years of making the wrong recommendation and not having it come back to bite me! Incredible.

I still am very curious when during the 1964 production they started to use the non ac/6 cylinder supports in GTO's?

Tom and 64Lemans., Thanks for the contribution. Bart, sorry to have doubted you but after 30 years, I think being convinced in less than 24 hours isn't all that bad.

[Ccass]

Originally Posted by Lemans64

I have 2 rad supports and both v8 cars, both are the non a/c style. Still have original from my car, just rusted a bit so found another. did not know of the a/c support or would have looked for one of those. 2 inches make a big difference according to my wife, LOL.

build dates? Where built?

[Ccass]

Originally Posted by b-man

Hi Chris,

The logical answer is because GM is very cost-conscious and designed that support as a dual-purpose part. It can be used for the non-A/C 326 cars as well as for the standard 6-cylinder cars by simply using that sheetmetal baffle when installing the narrower radiator. GM wouldn't have designed that core support solely for 6-cylinder use unless it fit the 6-cylinder radiator without the need of the baffle plate.

Bart

I was thinking about the same cost-consciousness on the other side. GM just had just dropped a big motor in a small car. If I'm the engineers, I already have an AC support for AC cars, why don't I save production and service nightmares by giving all the GTO's an AC support. There had to be speculation that the bigger motor needed a bigger radiator? And from Tom's info, that's pretty much what they did....at least in the beginning.

[John V.]

Wading in to this discussion.

First, this only applies to '64. Things changed in '65 so don't assume what I am about to explain applies to '65.

For my own benefit, I will refer to the '64 core supports as the Tall Core Support and the Short Core Support. And I will describe the rads used by their dimensions. I know some guys say 3 row and 4 row but that is meaningless to me and not how PMD described them.

Tom V. I think you have crossed something up. I am pretty certain you DO have the Tall Core Support in your factory Tripower GTO.

I have explained in the past that the Tripower GTO started the year getting the 17.5" tall x 2-5/8" thick radiator. It also got the 3.55 axle. This rad was considered the HD rad option for the GTO but since it was always used with Tripower I do not know if it was included at Extra Cost or part of the Tripower "package".

In early January, PMD decided to switch the Tripower to the 3.23 axle. For a time, all Tripower GTOs continued to get the 2-5/8" thick rad but around March, they started getting the 17.5" tall x 2" thick rad that was standard on all 4 bbl GTOs without A/C.

I believe this was done because PMD believed the thicker rad was not needed with the 3.23 axle.

In any event, at this point if you wanted the HD rad, it was an extra cost option. It was a MANDATORY extra cost option with 3.55 or 3.90 axle. But since I have no original Window Stickers from this time period I do not know how it was treated at that time, additional extra cost or not.

Once it was removed from the standard Tripower equipment content, it definitely was an extra cost option and you had to order it. It continued to be MANDATORY at extra cost if you special ordered the 3.55 or 3.90 axle.

With A/C, all GTOs got the 17.5" tall x 2-5/8" thick radiator.

Consequently, ALL '64 GTOs required the Tall Core Support. Different insulators were used depending on rad thickness.

We know factory build errors did happen so I cannot say that a Short Core Support was never installed in a '64 GTO, but that should be a very rare thing.

All 6 cyl Tempests got either a 15.5" tall x 1.25" thick rad or a 15.5" tall x 2" thick rad.

Consequently they ALL got the Short Core Support, even the A/C builds. These 6 cyl only rads did not have an oil cooler since the Super Turbine and Powerglide auto trannies that were used as alternates to each other were both air cooled.

For the 326 Tempest builds without A/C, the rad was a V8 version 15.5" tall x 2" thick.

For a 326, the Heavy Duty rad option was 15.5" tall x 2-5/8" thick. This rad was MANDATORY if the 3.55 or 3.90 axle was special ordered.

These builds all got the Short Core Support, same one as for a 6 cyl.

A 326 with A/C got the 17.5" tall x 2-5/8" thick rad.

Same rad as might be used in a GTO and same Tall Core Support used.

For the V8 rads, each version came with or without oil cooler. The oil cooler was needed for the water cooled Super Turbine auto trans but often was used in a man trans build with the oil cooler plugs left in place. The V8 rads without oil cooler could only be used in a man trans build.

The A/C option was pretty rare in a '64 Tempest, so you won't find too many that were built with the Tall Core Support.

Tom, I would really like you to confirm that your GTO has the Tall Core Support. Pretty sure it does.

Anybody that believes they have an original Short Core Support in a '64 GTO, I'd like to hear more. Unless evidence is clear, it would be pretty difficult to know if a GTO had front end collision repair with used parts from a wrecking yard resulting in the Short Core Support.

A factory error is not impossible. For KC and Balt builds, the PHS doc will show the intended rad. And the intended rad would dictate the Core Support that should have been installed. Doesn't mean the factory didn't mess up but at least clear evidence of what was intended.

The production of the '64 GTO meant that the usage of the Tall Core Support probably more than doubled from how many would have been needed for the V8 A/C Tempests. From a cost perspective, that probably was a good thing. Still the Short Core Support usage far exceeded the usage of the Tall Core Support.

The above outlines the rad and Core Support usage by application.

But this thread was about the possibility of modifying the Short Core Support to allow the usage of the 17.5" tall rad.

The upper maybe 80% of the two '64 Core Supports is identical. The mount to the frame area is identical

The Tall Core Support measures about 22-1/4" at the center from the upper most top rail to the lower flat bottom. The bottom is a separate fabrication that was spot welded to the upper portion of the Tall Core Support.

I don't have a Short Core Support to measure. Looking at b-man's pic of one, it also looks like the bottom was a separate piece that can be removed by cutting out some spot welds.

If somebody could replicate the bottom piece of the Tall Core Support, it would be fairly easy to cut away the bottom of a Short Core Support and graft on the repro bottom.

I would think you could do it without having to incorporate the frame mount portion which would greatly simplify the fabrication, just cut the Short Core Support off 4" below the top of the frame mounts.

I don't know what kind of market there would be for such a thing. It wouldn't be exactly correct looking unless you opted to fabricate the bottom with the frame mount sections as part of it. And it could be tricky to align it and spot weld it. You could bolt the pieces together, but again not correct.

Other than to make it look correct, I'm not sure the mod would be worthwhile. With a modern rad you probably can live with the Short Core Support.

ccass, after writing all this, I see that is the very thing you are planning.

It makes perfect sense.

I think Tom may have crossed you up. I think once he checks, he will confirm that he does have the Tall Core Support in his GTO and that never changed thruout '64.