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Drivetrain => 1964-1967 300CI Engine => Topic started by: BuickGS65 on March 09, 2024, 08:53:35 PM

Title: 1965 CROSSflow THREE row radiator 300 V8 - anyone running this?
Post by: BuickGS65 on March 09, 2024, 08:53:35 PM

Just wanted to confirm that a 3 core copper radiator will fit without modification in a 65 Skylark with CROSSflow radiator.

I was told OE was a 2 core with 1.25" core thickness vs. a 3 core which is 1.9375 core thickness.

Anyone running a 300 V8 Crossflow 3 core?

I think it will fit easily, but wanted to be 100% certain.


Thanks.

Title: Re: 1965 CROSSflow THREE row radiator 300 V8 - anyone running this?
Post by: WkillGS on March 10, 2024, 08:53:19 AM

Dan, I put a 4 row in my '66 Special. I think the rad was spec'd for a '67 GS 400, it was around 1998.
The 65-6 GS used wider tanks that would accept 3 or 4 row cores. Most of the small blocks used narrower tanks except for some wagon and HD cooling versions which used the wider tanks like the GS.
The wide tank radiators used a different top plate, the insulator cushions were different too. They mounted directly in the lower saddle of the rad support, without brackets. Insulators are avail from CARS or Steele.

I have an aftermarket aluminum Griffin radiator in my GS, 27.5" x 19" size. There are versions with in/outlets that fit Nailheads and another version that fits the 300-340 and 400-455.

Title: Re: 1965 CROSSflow THREE row radiator 300 V8 - anyone running this?
Post by: BuickGS65 on March 10, 2024, 09:09:56 AM

Thanks, Walt.  Are you using the 4 row radiator in your 66 Special using the small block top plate and the small block lower brackets? I’d like to keep it all “stock” appearing while upgrading the cooling capacity.

Title: Re: 1965 CROSSflow THREE row radiator 300 V8 - anyone running this?
Post by: WkillGS on March 10, 2024, 10:18:05 AM

Dan, I'm using the GS style top plate and insulators for the wider tanks.

You'll have to check with your radiator manufacturer to determine what width tanks they use.
US Radiator has a comprehensive listing. The 1966 page shows a GS 300/400 radiator with 2-3/4" mounts and the GS 401 using 3-1/2" mounts.
They do offer a 2-3-4 row option for the 64-66 300 radiator, but don't mention the tank size. Maybe they have the combo you are looking for.

 https://usradiator.com/radiator-finder?make=Buick&model=GS&_year=1966

Title: Re: 1965 CROSSflow THREE row radiator 300 V8 - anyone running this?
Post by: jmos4 on March 10, 2024, 10:55:54 AM

Hi,

My 65 Special had a 3 core when I got it, when it came time to redo I put in  4 core, I had to modify the top plate which involved flattening out the 2 bends where the rubber insulators are and getting GS insulators worked out fine and if you're careful should be unnoticeable.

Regards,
Jim

Title: Re: 1965 CROSSflow THREE row radiator 300 V8 - anyone running this?
Post by: BuickGS65 on March 11, 2024, 07:31:55 PM

Thanks everyone.

I believe I put a 3 row in my other 65 Skylark 20 years ago. Did some additional measuring, and it looks like the 3-row will fit comfortably.

Appreciate all the replies!