I HAVE BEEN BATTLING A TEMP SPIKING PROBLEM IN MY SON'S 87 CAMARO AFTER INSTALLED A NEW JASPER ENGINE, CHANGING TO VORTEC HEADS, COMP XTREME ENERGY ROLLER(270)PERFORMER RPM INTAKE AND CARB.
THE CAR WAS A TPI BEFORE, BUT THESE CARS WERE AVAILABLE IN A CARB SETUP, I USED ALL FACTORY PEICES TO CHANGE IT OVER AND WE ARE NOT RUNNING A COMPUTER ON THIS SET UP. THE COOLING SYSTEM SEEMS TO BE AIR LOCKING TEMP WILL SHOOT UP TO 240+ AND DROP BACK TO 170 OR LESS, DRIVERS SIDE HEAD FEELS HOTTER THAN PASS AND THATS WHERE SENDER IS, GAUGE WAS FINE BEFORE ENGINE CHANGE AND TRIED A NEW SENDING UNIT AS WELL. THE RAD DOES NOT SEEM TO GET THAT HOT AT ALL, TRIED 2 THERMOSTATS(180)AND ALSO DRILED A HOLE IN THE LAST ONE, STILL SAME
PROBLEM, ANY BODY RUN INTO ANYTHING LIKE THIS
THANKS ROB...

Rob,
Try getting rid of the all capital letters first...very hard to look at and considered as "shouting" by most.
Which intake gaskets did you use ?? The TBI and TPI gaskets have one end blocked off at the water pasages. If you inatall one or both of them backwards, it will cause problems very similar to what you are describing. The front water passages have to be open, the blocked ones with the small hole go to the back.
Hope this helps,

sorry on caps, using felpro h/p gasket set #1255 , the 1/8 thick vortec only gaskets, they are open on both ends for coolant, but the intake is not, thats not it, thanks Rob...

You type faster than I do.

Vortec heads have a dedicated gasket. They fit either side. No blocked coolant passages.

Bad sender? Can't rule out 2 bad stats either. Test one in a pot of water w/ oven thermometer on stove. The cycling says thermostat.
What did you do for the pump bypass?
Not that I'm running one w/my vortecs.
If how did you run the heater hoses. With the TPI TB heater and oil cooler and bypass valve, you might have got something backwards.

I have a friend that had a similar problem. He solved his problem by installing the bypass hose.

the tpi set up does not use a bypass hose and I did not install one, you guys may be on to something here, when the car is running if you put your hand on the upper rad. hose you can feel almost a hammering inside the hose at times, I'll
look into setting up a by pass hose, Thanks Rob...

Somewhere in that year range,didnt they change the waterpumps? Run a different direction? if that was so wouldnt it cause cavitation? Just floating ideas...

I've gone through as many as five new thermostats before I found one that functioned properly. I even managed to get a pair of Robertshaw thermostats, back to back, that didn't function properly.

In all of the above instances, symptoms were exactly as you describe. Temps cycling up and down, never settling. I only noticed the pulsations once, I hadn't checked for it before then.

I have a box of thermostats at home in Baton Rouge, each of them displaying different characteristics even though they're the same brand and rating. I just couldn't bring myself to throw them away.

You didn't pick up an old rebuilt water pump? I put a 327 together for the Nova and it acted like yours. I took out the plug in the head and there was no water at plug. It turned out to be the rebuilt waterpump had such a worn impeller it wouldn't push the water through the engine properly.

Well the heater hose setup is totally different from tpi to carb set-ups. Thought we had it, changed it over to the carb arraingment(normal hose set-up 1 from water pump, 1 from intake) now
the water flow in the radiator is just a trickle, still jumps temp up to 240 !!, changed therostat
again and tonight removed a year old (new)waterpump, removed back cover, everything looks ok
shaft seems tight, going to put a new one on anyway, this is getting very old, any more idea's
Rob...

How did you fill the block with water? Sounds like a huge air pocket. You can't just re-fill it through the radiator, need to remove the thermostat and fill the block completely, re-install the thermostat and housing, then continue filling through the radiator. It will also need to be refilled once or twice after heat cycling.

Jody

is the belt turning the pump the right way? clockwise when viewed from front. It definately sounds like a circulation problem, does the lower radiator hose also get hot?

The pump is turning correctly, the air pocket is a possibility and I will give that a try when I put a new water pump back on tonight, thanks guys Rob...

My vortec 350 does the same thing. Started after I put in a new higher temp thermo for the winter [went to 180*] I've had two 180* thermos now and both do it. Spikes a couple time while warming up, then settles down. I don't worry about it much.

Ok, by removing thermostat and filling block(twice)that cured the air lock problem, thanks to all, Rob...

Cool!

Jody

so it was just an air bubble then?

that was it, had to run twice and refill, cured problem after that, Rob...