96 cobra shortblock build

JrFox said:

I just recently purchased my cobra sometime around sept. and been trying to figure out why its overheating. I came to a understanding that i need to rebuild the head. So i decided that i have to tear the head off i should build the short-block. I talked to my brother talked to chicane, but did not really help (sorry i'm not some one to throw dirt on someone's name) lets just say it didn't clear many things up. Then i talked to CHP and they priced their pro-street kit (short block assembled) ran 3799. In the future i will go with forced introduction. (Most likely twin turbo) Just wanted to get some feed back on my situation, and i'm oped to suggestions and different options. I do live by torrence CA, so its somewhat convenient for me.

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Rebuild the head to fix over heating? Did you blow a head gasket? Havent heard of head rebuild to fix heat issues. The most common heat issues with 4.6's is improper burping when doing a coolant change. I think we need more info on the head problems.
Why are you doing a short block? Did you do a compression and leak down before pulling the heads? Are you seeing oil pressure drops at temp? Have you done a blackstone oil analysis? There are many steps you should take before dumping money into un-needed work.

96 Cobras have a TSB on the cooling system. The radiator is too small and the TSB they switch it to the 97+ Cobra radiator. Since your car is out of warenty you have to do it yourself, you have to drill new holes for the radiator brackets because the radiator is wider. Pretty easy job. The other thing to check is the Thermostat, when I bought mine the previous owner took it out cause he didnt know how to burp the system. Car was always running with the needle pointing at the "L" on NORMAL which is way too high. I put in a OEM thermostat and properly burped the system and the car NEVER gets warm enough to turn on the fan, always between the N and O on the gauge. Burping the cooling system is very important on our cars aswell. The crossover pipe (in front of the alt ) had a plug you have to unscrew (1/4 drive wrench) run the car and add coolant in that hole till its full with the car level and that will get all the air out of the system.
Hope it helps.

In 1996 I lived in Redondo Beach. At that time, my 96 Cobra only had an "overheating" (which meant running hot) problem when I was in the high desert between Apple Valley and Vegas/Kingman. In Torrance/Redondo, the car ran fine. I did have the TSB performed back late 1996 though...

JrFox said:

Well see, i bought the car from a body shop, the previous owner was running nitrous in the system. First things first i properly burped the system, and added a 160 thermostat from brothers performance, the car would still start up with a ton of white smoke then after a while it (10-15 min) would overheat. I ordered compression and leakdown tools from snap-on and I'm just waiting on them to come in. (our tools didn't fit) But the only reason im asking on peoples take on the situation is cause the car is at 100k miles and has been through hell, so i expecting the worst. I spoke to 2 of the tech at don knott ford and they told me that around those miles the car starts to take a crap. Thanks for the all the help!

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It sounds like a head gasket or a crack block/ head. The compression test will tell you quite a bit. The 160 stat is not nessary and in most cases does more harm than good. The smoke is telling me that you are leaking into the cylinders from somewhere. The nitrous statement kinda scares me. You may be looking at a new engine not just doing a short block. If the compression test comes back bad then you need to see where its losing it. Rings, valves, gasket, crack.

Keep us updated and we will hope for the best.

The new info helps alot. I dont think you are looking at a new engine but I do think the heads will have to be worked. My 96 had a Vortech on it before I bought it, caused the head gaskets to blow. Thats how the previous owner bought it, overheats after running a few min. He pulled the engine and decided the heads were too warped and put in new heads with the old heads valve train. He also dismantled the block and said everything was in perfect shape so he just did new rings, testamony to how good our engines are So yeah with the miles and nitrous and the white smoke I would bet money that you just need new headgaskets and resurface the heads. BTW mine was at 104K when it blew them and had been running the blower since 22k. I guess at around 102K the first owner decide to step the boost to 14 lbs and the tired gaskets didnt like it.