71 Big Block with new Griffin Radiator

[engineer_gregh]

I thought you guys might like to see how the Griffin radiator fits. I had to use modified brackets as the radiator is a little taller. I also used the kit with two 1600 CFM fans, so I no longer have the stock fan. I went to this set up as after rebuilding the engine, I was running too hot, the stock radiator couldn't keep up especially with the AC running. The kit number from Griffin was SU-70013, and the 1600 CFM fans were a ~$20 upgrade over the 1300 CFM.

[alsriv2]

Nice. Where did you locate the upper mounts?

I will be upgrading my cooling system after I install my newly OH'd 396BB.

Is this radiator setup available online?

Thanks for the posting.

[engineer_gregh]

I'm not sure where my engine builder got the mounts from, I believe he said they had been laying around his shop for a couple of years. I'll ask him later this week. If I had to guess it was probably Jegs.

[engineer_gregh]

I ordered the radiator setup directly from Griffin. Tom Knottek at 864-845-5000 was the tech I spoke with. He was very helpful. I decided that all of the help he provided was worth paying a few extra bucks and buying directly. Summit does carry it with two 1300 CFM fans. The link on Summit is http://www.summitracing.com/search?keyword=CU-70013

[darkhorse970]

It looks nice. Did this resolve your heat problems? How about in traffic? What were you running before you swapped to this setup?

[engineer_gregh]

Thanks. It did resolve the problem. I would run about 190 degrees at 45mph and about 195 at 60-65 mph. I removed the extra transmission cooler strapped to the a/c condenser and it lowered my 60-65 temp down to 192. If I got into traffic it would creep up to as high as 210-220 degrees especially if I was running the a/c. We tried a high volume water pump, 7 blade fan with clutch, water wetter, straight water, 50/50 mix, and a small electric pusher fan on the a/c condenser with no real results. The best improvement was removing the external transmission cooler. When using an infrared heat gun we were only getting a 3-4 degree drop between the bottom of the water pump and the thermostat housing and 10 degree drop between the drivers side and the passenger side of the radiator. You should see a ~40 degree drop between the drivers and passenger side of the radiator. We installed a new 4 row brass radiator and it was not as good as the original 4 row that was on the truck. Now it never goes above 190 degrees and most of the time stays at just over 180 with or without the a/c. I do notice the fans run more with the a/c on. Huge improvement. By the way the Griffin holds almost 3 and half gallons of 50/50 mix. I'm only running the 50/50 mix with no additives. Griffin will void your warranty if you use water wetter or such. I hope this helps. It was a lot of hard work and frustration, so hopefully this helps someone else from weeks of troubleshooting.

[darkhorse970]

That's great info for a guy doing a big block build. Thanks!
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[engineer_gregh]

Mine is a numbers matching 402 block with 65-66 325 HP heads. I used Comp Cam High Energy 268 with matching lifters, springs, retainers, pushrods. Double roller timing chain, ported and polished heads with 3 angle valve job. Had to bore the block 30 over and used aluminum pistons. Also had to replace the crank with a forged steel, mine couldn't be turned. I kind of wish I had gone with the gear drive for the timing, I like the sound.

[del4fun]

Nice job with the Griffin! Is the 1300 CFM fans loud when they both run?

[engineer_gregh]

I upgraded to the 1600 CFM fans. Not bad with the hood closed. I used my iPhone to record it running but the file is too big to attach it to the thread.

[alsriv2]

Many thanks for sharing your information with us.
I have been concerned about the cooling with my new engine and the upgrades my builder incorporated. Right now it Dyno's 469hp and 450+ tq.

[engineer_gregh]

What mods did you do? What cam are you running and what did you do to the heads to push that much horsepower and more importantly torque? Are you going to run headers and A/C?

[67ctener]

I know this is an old thread but was curious how you still like your radiator? I was considering buying one but they have poor ratings on summit so now I'm not sure

[engineer_gregh]

Hi Scott, I'm very happy with the radiator. I've put about 5k miles on the truck and no issues. If you do go with an aluminum radiator just remember to not synch it down to tight. The frame on these trucks flex a lot and will crack the radiator, you can probably figure out how I know that. With moderate pressure I can move the radiator up and down and side to side.