How to install a Cobra Heat Exchanger

[Blown 4-Banger]

Ok on request from NJHK, I put my how-to on here from css.net. I'm going to tell you how to install a Cobra heat exchanger in a Cobalt SS S/C. Its a fairly long and difficult project, but I got through the entire project and spent less than $100!!!
Things you will need:
- Cobra Heat Exchanger (DUH)
- 4 Metal "L" brackets, 2 long and 2 short
- Hack saw
- Drill
- 6 self drilling sheet metal screws (or other mounting hardware)
- 4 small bolt/nuts
- Lots of zip-ties
- 8 Hose clamps
- A good length of 3/4" heater hose (8-10 feet)
- Pliers
- A set of tools (wrenches/sockets)
- A jack and 2 jack stands
- A person to help you
- A clear head & lots of patience

Heres the heat exchanger, your going to cradle the heat exchanger with the 2 large L brackets, and secure it to the heat exchanger via 6 zip-ties. Then your going to cut the long L bracket so that the top of the bracket only sticks about 1/2" to 3/4" above the top of the heat exchanger. Then just cut a little bit off the small bracket so that it doesn't touch the zip-ties.

Then your going to take the brackets off, and line them up ready to drill the holes.
Your going to drill 2 holes near the top of the bracket. After you've done that, secure the brackets together with 2 bolt/nut assemblies. It should look like this
Once again secure the new bracket to the heat exchanger via zip-ties.
Due to metal to metal contact, we used this cloth stuff (not sure what its called) to place between the heat exchanger and the brackets, it helped prevent rattling and made a tighter fit.

[Blown 4-Banger]

At this point your heat exchanger should look like this
Now that the brackets are out of the way, we can focus on hose fittings. Due the lack of space, we had to use 2, 3/4" 90 degree elbows, we soldered two pieces together for ours, I'm sure you could find a single piece fitting somewhere.

We then cut a piece of hose to about 2" in length, we put one end on the heat exchanger fitting, and one end on the elbow fitting. The piece of hose should be just long enough to keep the two fittings from touching. Then use 4 hose clamps to secure the two fitting together.

Since the heat exchanger will sit so close to the front of the vehicle and to the air flow, I decided to do a lower mesh grill to protect the heat exchanger from flying debris. If you want to learn how to put a lower mesh grill on, Click Here

[Blown 4-Banger]

At this point we lifted the heat exchanger in place and made marks where the brackets were.

Now comes the messy/difficult part. Removing the stock coolant line. Your going to remove the stock return line from the stock heat exchanger to the pump, and put the new lines in place to plumb in the new heat exchanger.


This is the line you need to remove

Then connect the new hoses and route them out through the driver side front fender

[Blown 4-Banger]

Now cut the hoses to length and connect them to the heat exchanger

This is where it may get difficult, due the fact that there are now air pockets in the system, you need to bleed the system. We simply submerged the heat exchanger and return line (disconnected) in dex cool, and turned the pump on. It bled its self out and we re-connected the return line while submerge to eliminate exposure to air. It took a few tries but we got all the air bled from the system.

Now that the system is bled, place the heat exchanger in place and line it up with the marks you made earlier. Its a pretty tight fit, but if done right it shouldn't touch the a/c condenser

Now drill small pilot holes for the 6 self tapping screws. Then use an extension on the drill for sockets and drill in the screws

Now secure the return line with zip-ties so that it doesn't hang lower than the front bumper, or touch the a/c condenser. Now your done, lower the car from the jack stands and go for a test drive!

I want to give a HUUUUUUGGGGGGGEEEEEEE thanks to George (Cobalt_Supercharged) for all the help and support! I owe you one!!!

[black06g85]

a/c cond.... there is no use for that come on man.... lol

but yeah.. nice shit man. but I prefer removing the front bumper to make things a bit easier (only takes about 10 mins) and the top rad supports to give more room to play around...

[Admiral Jedi]

That's awesome. Much better than my head exchanger installation. I used nothing but zip ties!

[ionjentzsch]

I have thought about using this in a slightly diff way. I have thought about connecting this in line with with my radiator so that the engine coolant gets pumped through the radiator then into the cobra HE, then into the engine.

Since I will be boosted soon, I figure attempting to cool the engine down a bit more would prove to be beneficial.

My only issue with this is: If I decide to try this, finding a home for the HE will be difficult with my IC taking up much of the room.....Hummm

[en0onmai]

I've been told the Ecotecs like a little higher operating temp so doing this might not be as beneficial as you think. Especially if its just to cool the engine more. But I could be wrong.

[04cavalierss]

Thats a pretty good writeup however im a little lost on some of the pictures. I want to do this to my 04 cav, but still seem a little baffled.