Custom aluminum radiator

[Glenn M]

Consider a Ron Davis radiator...I have one in my V12 XKE
and it is awesome. I am considering one for my GT but it hasn't been pressing. Quoted $450 or so a while ago. Good Luck

[spamseptictank]

Thanks for the info everybody. Looks like I'll still be using the good ol' external oil cooler with some fancy ducting.
Grace and Peace,
Dave

[greensmurf20]

only took half hour to get to lake michigan and another half hour to find a place to park. temp was halfway, 85 degrees, crawling through town at 10-20 MPH. way home i got caught in traffic unlike last year. 65 degrees, and pretty much moved a mile in an hour, people on feet were doing better than us in the cars. at long standstills car woulud still get hot unless i kept the engine reved to about 2,000 RPM, to keep the fan pulling air through the radiator. soon as we started moving again the temp dropped to between the blue and first notch on the gage. i'm not a firm believer that radiators are a good investment, they DO make all the difference.

[jordan]

I have a 3 core radiator and no fan shroud and it has never been past half way on the temp guage.

[jpavlack]

For whoever successfully has installed the Griffin radiator on their Manta/1900, what did you do with the lower radiator hose? It looks like it may have to be trimmed but the hose diameter looks like it is too small to fit onto the radiator.

[jtb]

You could try AFCO for a custom rad:
AFCO: Cooling

See what they quote, I'm guessing it would be between the Griffin and the Ron Davis, but worth a call or email.

jtb

[RallyBob]

Originally Posted by jpavlack For whoever successfully has installed the Griffin radiator on their Manta/1900, what did you do with the lower radiator hose? It looks like it may have to be trimmed but the hose diameter looks like it is too small to fit onto the radiator.

I used a custom setup consisting of a 1.5" 90* silicone connector, a 1.75" 90* silicone connector, and a straight piece of aluminum tubing that is made from a piece of 1.5" that is welded into a piece of 1.75" tubing. Not sure what others have done to be honest...

Pic of upper hose connections.

[oldopelguy]

I used a brand new hose and stretched it onto the radiator.

[jpavlack]

oldopelguy,
I'm assuming you cut part of the hose? The lower outlet on the opel radiator comes out the side. On the Griffin radiator it comes out behind radiator

[oldopelguy]

Mine was actually in a Kadett, with quite a bit of metal work involved. A Kadett lower hose should work fine, though, on a Manta.

Often times you can fit everything together, figure out what sizes you need the ends to be, and mock up something in the general shape. I've used all sorts of things, from pool hose to bicycle inner tubes filled with expanding foam to make myself a model of what you need. Then, model in hand, head to your parts store and ask them to look at what they've got for hoses. It'll be pretty obvious what won't work, and scrounge around a bit to see if you can find something right, or close enough to right you can cut a bit off and use it. I've never failed to come home with something that'll work this way.

[neuropel]

Originally Posted by oldopelguy This isn't a radiator custom made for an Opel Manta. It is a universal racing one Griffin already makes that is exactly the right size for a Manta already. It just needs the proper brackets to mount it in the Opel. If you look at the pics Bob posted of this radiator, you can see the parts he had to weld onto the side tanks and the bottom for it to be a drop in using the stock Opel mounts. I have some brackets I made to replace the rubber mounts on the sides of the rad and a mount for the bottom so that the rad can be dropped in without any aluminum welding. The mounts I made bolt in to the body and channel the tank on the sides and bolt to the bottom to use the Opel mount there. Same effect, but like I said, no welding aluminum.

I'm ordering one of the Griffin radiators from Summit - Stephen, do you still have the plans for the brackets, or even possibly still have some brackets available?

Todd

[GoinManta]

Ditto..

[Mr V]

People .opel gt source has them.

[oldopelguy]

No pictures, though I'll try and scrounge up my camera and get something before I head back to SD tomorrow.

The Griffin Radiator is a side tank variety, with "U" channels on the top and bottom of the radiator. On the bottom I cut a 2" long piece of square tubing the size to fit either over or inside the "U" in half length-wise to make my own steel "U" to nest with the aluminum one on the radiator. I then drilled 4 small holes in the overlapping portions of the two channels and bolted them together with 4 small machine screws and nuts. Once the radiator was fitted in place I marked the steel "U" with where the top of the stock Opel mount needed to be and drilled a hole through it to attach the stock lower radiator bushing, using an additional nut I scrounged up from somewhere.

Were I to do it again I would just get a chunk of aluminum block to fit inside the channel and stick out about 3/8". In the part sticking out I'd drill a couple holes through the block and match up a couple of small strips of aluminum to either side to pinch the sides of the channel and clamp it that way. Then for the stock mount I'd drill and tap a hole in the bottom to screw it into instead of using a nut.

Why the change? So there's no steel bolted to the aluminum and no corrosion. I ran the radiator in salty NY for two and a half years with the unpainted steel bracket and had just the beginnings of corrosion on the radiator.

The side brackets were even less complicated. Two pieces of 1"x1/4" flat steel about 6" long were cut and had the ends rounded and smoothed off with a grinder. One 3/8" hole was drilled in the center of each piece of flat stock. On the stock Opel radiator shroud there is a rubber "nub" on either side captured by brackets on the top sides of the radiator. Pop them out and you have a pair of holes on either side through which a bolt can go with a nice fender washer on one side.

Set the radiator in place, with the bottom mounted solid and figure out where the flat straps need to be bent to form them into "U"s around the tanks on either side of the radiator, leaving yourself a 1/8" to 1/4"gap between your bent steel and the radiator. Once you are happy with your bends, paint the steel brackets then lube them up with some dish soap and slide 4 appropriately sized chunks of 3/4" heater hose over them, covering everything but the holes. Insert 3/8" carriage bolt through the holes from the inside out, so the head sticks out less than the rubber from the hose, insert them into the holes in the body, add a washer and double nut.

Same type of mounting as stock, just as easy to insert and remove, I think just as solid or more so, and nothing to it. You get extra bonus points, though, if you make your inner fingers on the side brackets and the inner piece of strap pinching the bottom bracket long enough that they stick out into the radiator exactly enough to use them to mount an electric fan.

[neuropel]

I have since received my Griffin radiator, and there are 4 welded nuts on the back face of the radiator (i.e. same side where the hoses attach). I would assume these are for attaching a fan shroud of some type since they are in the same general area where the fan shroud rests on a stock radiator. Unfortunately, they're no where near the right distances apart to use for mounting the stock shroud.