Radiator replacement problems... not cool!

[undy]

Originally Posted by rustyBob

I have never liked the fact that they rate them by horsepower rateing, they are a heat exchanger and should be rated by B.T.U.'s. I spent 10 years working in a nasty dirty smelly radiator shop and i have never heard of so many people haveing overheating problems or "cooling" problems in my whole time working at that shop as i have heard here on Club Cobra. Ihave built some big radiators and have heard of people that can't cool a small block Chevy with a radiator out of a Suburban........MAYBE it's not the radiator that's the problem.........under what conditions does the car run hot ...are you sitting still in traffic....running down the highway at 70 mph turning 4 grand on the tach.....a little info would go a long way on helping you solve your problem and MAYBE you wont have to throw a credit card at it to fix a problem that may not exist with the radiator.

Unfortunately, "horsepower" is sort of a universal rating system, one that the racing layperson understands. It's not exacting but it gets the concept across to the masses. If you rated in BTUs you'd have to have an accepted standard, @ a given engine temp, @ a given outside ambient temp and @ a rated CFM ... then you'd have to get it standardized in the industry .... not likely..

Our Cobras, by design, have small frontal areas and engine compartments. That's a recipe for overheating woes, more so than the "average" vehicle. The small frontal area severely limits the radiator core face area. (my actual core size is 18" x 17", about VW Scirroco size) Since you can't grow in size left to right or top to bottom that just leaves core thickness (wider cooling tubes) The tight engine bays (tighter with big blocks) makes it harder to get rid of the air too, once it's pulled through the radiator. I honestly feel that my existing radiator, coupled with the newer high CFM fan, will adequately cool my motor. The larger capacity radiator will give me a bit of much appreciated cooling redundancy. I really don't want to deal with this cooling issue again.

Originally Posted by elmariachi

Ughhhhh, that sucks! Hopefully they can mod it for you. Or surely there is a Tig artisan somewhere close to you that can. Hang in there Dave.

Jim

Ton's of good TIG/MIG guys around here.. It's dealing with the epoxy/leak issues that stymies everyone..

Originally Posted by vettestr

Dave,
I feel your pain on this one ! If you run into trouble with Griffin not wanting too modify the radiator there is still hope. I have welded a radiator with the epoxy on the tubes myself. I had to add a port and it was epoxied. I rigged up a way to hold it in the needed position and I filled it with just enough water to cover the epoxy but left as much air as possible. I had to really throw the heat to it but no biggie, it worked.

I HOPE Griffin is willing to do something!!!??? I plan on paying for the mods/new radiator anyway as Griffin didn't screw it up, just a little ignorance on my part. I'm holding off shipping it back to them until I can get them on the phone this AM. I don't want it to be on the way to them if they're unwilling to help me out.. It'll be off to Fleabay otherwise.. I'll do some more research today on acceptable ways to repair with that epoxy sealer.

Dave

[kitcarbp]

Hi Undy, I just finished my Griffin install and noticed your thread. The first rul of thumb is have maximum frontal area, followed then by going deeper (1.25 to 1.5 " tubes. If you are running a rad as small as 17" x 18" ( 306 sq in) you will struggle to cool anything over 400 hp even with 2 rows of 1.5" tubes for street duty, I would have expected them (Griffin) to give you better advice and inform you of the fan cfms you need. Hope is not lost in these cases because the solution is to "over-fan" the rad with very high cfms and a good shroud. BTW 2,000 cfm is for smaller hp engines, not our monsters. I threw my flexalite in the bin. Its an aftermarket joke. I mean you need 4,000+ cfm or more (like the Taurus fan), as long as your alt/harness is up to the job. I went the route of twin 13" SPAL fans to get ,max rad core area coverage. check my gallery for install pics. I am running a 16 x 26 core (for 416 sq in) with 1.25" tubes with about 450-475 hp in my application. My rough calcs. tell me I should be good to 550 hp (Griffin claims 600hp) but I will spend 1% of time at rated max power anyway. Engine compartment must be vented you're right, to avoid recycling the hot air. Are you using vac advance on your dist ? That will also help reduce engine temps. Good luck.

[undy]

Yep, I'm limited to a overall sized 22" x 19" radiator, by frontal frame design .... can't go larger (H x W) if I wanted to. My only possible radiator cooling "growth" was a thicker core and more CFMs, which I've done to the max.. Griffin rates "categories" of radiators by horsepower, 1" tube (400), 1 1/4" tube (600), 1 1/2" tube (800), 1 row, 2 row ...etc. If you have a 2 row 1 1/2" tube then it's 800 hp rated, no matter what the face measurements are.. It just gives a "ballpark" idea of what total heat rejection capacity it has. I knew all that going into it. (30+ years of mechanical engineering experience) My smaller core won't permit the use of 2 fans due to size constraints. You have 4" more radiator width that I do, a good thing ... for you. I'm running a Powermaster 140 amp 3 wire alternator with a #4 wire to my connection point and a #8 feeding the fan. I have enough amperage redundancy in my electrical system to pretty much handle anything I throw at it. The distributor's a MSD Pro-Billet, 100% centrifugal.. Changing it would be my last ditch effort. I really don't think I'll need to go there though...

Dave

Originally Posted by kitcarbp

Hi Undy, I just finished my Griffin install and noticed your thread. The first rul of thumb is have maximum frontal area, followed then by going deeper (1.25 to 1.5 " tubes. If you are running a rad as small as 17" x 18" ( 306 sq in) you will struggle to cool anything over 400 hp even with 2 rows of 1.5" tubes for street duty, I would have expected them (Griffin) to give you better advice and inform you of the fan cfms you need. Hope is not lost in these cases because the solution is to "over-fan" the rad with very high cfms and a good shroud. BTW 2,000 cfm is for smaller hp engines, not our monsters. I threw my flexalite in the bin. Its an aftermarket joke. I mean you need 4,000+ cfm or more (like the Taurus fan), as long as your alt/harness is up to the job. I went the route of twin 13" SPAL fans to get ,max rad core area coverage. check my gallery for install pics. I am running a 16 x 26 core (for 416 sq in) with 1.25" tubes with about 450-475 hp in my application. My rough calcs. tell me I should be good to 550 hp (Griffin claims 600hp) but I will spend 1% of time at rated max power anyway. Engine compartment must be vented you're right, to avoid recycling the hot air. Are you using vac advance on your dist ? That will also help reduce engine temps. Good luck.

[elmariachi]

Originally Posted by undy

I'm running a Powermaster 140 amp 3 wire alternator with a #4 wire to my connection point and a #8 feeding the fan. I have enough amperage redundancy in my electrical system to pretty much handle anything I throw at it. The distributor's a MSD Pro-Billet, 100% centrifugal.. Changing it would be my last ditch effort. I really don't think I'll need to go there though...Dave

You get the radiator issue resolved and I'll be my hat that your wiring and the Taurus fan handles the rest.