383 stroker overheating

for starters throw that edelbrock in the lake... that 383 motor need at a min. of a 750 to an 850 carb. I recomend Demon carbs. I use them on all my motors. they flow better and tune just like a holly. Get one with mech. sec. As far as the cooling, take the heads off and make the flow holes that are on the head gaskets a little bigger. That will make the flow through the motor better. Next put a high flow water pump on, somewhere around a stage 1,2. You can also plug the bypass hole in the water punp. It is not needed. By doing that will create more flow. if you do that you need to bypass the heads. Jegs part# 555-51100. This takes the heat off the heads. This should do the trick. Remeber it all about flow. Thats why taking the t-stat out cools it down, but that is very bad for the heads.  

In my 383 with alum heads and 10.7 to 1 comp with stock type water pump and no fan what so ever it runs 182 degrees with a 180 thermostat no matter what the air temp.Think i would be looking for some type of blockage.

good luck.

PS. DUMP THE CARB! get a holly or demon 750-800 i've heard rummors about the edel running to lean esp. on idle circuit.Just curious you don't have intake gaskets with blocker plates installed backwards?  

I sure appreaciate all the info. I should be home on leave in a week and will check things. I am sure that the intake gaskets are on ok. It did not have any kind of blocker plates. I have a 192 thermostat in it right now. I noticed that when it opened up it would flow through the coors at a slow rate. I did notice that the coolant did drop as I added more coolant. But for some reason, it did not seem to flow fast. I have a 6 pound radiator cap on it now. Is this ok or should I go back to the 12 pound cap. I did purchase a 650 holley, maybe I should of went to a bigger carb. Is the carb worth a try or maybe should I send it back and get the 750? I still have the air conditioner cooler on the front that is not in use. Maybe taking this off may help. Back on the thermostat= should I go back to a 180 degree or less? I sure appreaciate the imput from all of you. Thanks  

send that 650 holly back and get a 750 to an 850 holly or demon carb. The 650 cfm carb is just like putting a restrictor plate on your motor. That and it will not flow the fuel that your motor needs. That WILL make your motor run hot and run the risk of cracking your heads or block deck. Remember lean is mean. Now also you need to leave the 180 t-stat in. One cheep way to make more coolant flow is to plug the bypass hole in the water pump or block (which ever), and drill four .080 holes in the t-stat. That will take the flow though and out the top instead of though and out the bottom were it can be reheated again.

good luck  

Thanks, I appreaciate the info. I will take the 650 back and change back to the 180 thermostat. I have seen an article about drilling the thermostat to take care of air lock. I sure appreaciate the info. I will be home on leave for two weeks, and in hopes to get this taken care of. Thanks again.  

No prob. I've been there before. If you have anymore problems just holla.

P.S. don't forget to block the bypass hole in the water pump. If not and you drill the holes, you'll just be spinning your wheels.

good luck  

Thanks, I should be home in a week to try the changes. What would you suggest to plug the by pass on the water pump? Could I just take a regular gasket and cover the hole? Or maybe would there be to much preasure? I just hope this does the trick. I have had that motor in and out of that car so many times. I gave the car to my boy a few years ago and want to close the chapter on that thing. Would the over heating problem cause the oil preasure to drop? My boy mentioned that when it got up around 220, the oil preasure dropped down to 30. Im guessing if it got that hot, things do expand, and with that in mind,,,you will have that. It is a fresh rebuilt motor,everything is new in it.  thanks  

Ok plug by threading the bypass hole with a tap. Then use a female hex plug. Its not hard. Use teflon tape or a liquid thread sealant (recomended) to seal the pug up real good. When putting coolant back in, use a 20% coolant 80% water and a bottle of water wetter. That does help.

As far as the oil droping to 30 psi is that at idle or open throtle. If at idle or crusing that ok, crusing shoulb be around 40psi. Open throtle around 5,000 rpm should be about 65ish 70 to 80 perfect.

If your worried about it then get a high volume pump, a remote oil cooler with fan, and take the rear main cap off bur gring the oil collecter bowl a drill out the oil path from the pump to block. Make it the same size as the hole thats in the block.
One more thing. Header wraps work. And what size headers do you have.  

Thanks, I should be home soon and will check out what I have to do. I have a high volume oil pump in the motor. It is a fresh built motor. It was running around 70 psi cold as that should be normal. When it warmed up, it dropped down to around 30. When I was home the last time, i built that motor to the 383 built. I ran it about 20 miles and found that the oil preasure dropped. At normal cruise speed it dropped to around 10. I pulled the mains off and found that the new crank had wear on it. I had to pull the motor and put in a new crank and bearings. Everything was checked for clearance as .0015( 1 1/2 )thousands was what i was getting. I did replace the high volume oil pump,,,,,added a high dollar 7 quart pan and matching pick up. The headers I have are, im guessing  1 1/2-or maybe 2 inch comming off the heads. What kind of wrap is out there for that? I guess I will have my hands full for the two weeks home. Once i plug the water bypass hole, will that make the water run much faster than what im having now? I sure appreaciate it. Thanks  

Sounds like the oil is getting to hot as well. Try to put a oil cooler on it. Conventional oil doesn't like getting above 270 deg. thats about when it starts to brake down. (you'll notice it turning black sooner than normal).

The header wraps are made by (Cool it, Thermot tec). You can find that in jegs under exhaust or at advanced auto parts. The wraps will make the header act like a factory mantifold by keeping the heat away from the motor and out of the engin bay. Not to mention a little more hp.

Now this 383 sould be running cooler and better after all that. If there is anything else just ask.  

Thanks. I may of missed one thing. Do I tap and plug the block, or plug the water pump by-pass hole? I will also need to go back and check the timing. I was told by Jeg's that I should set the timming at 18 degrees. I have been reading the forum and finding that 18 is not enough. If I take the vaccum off the distributor, crank it up to 3 grand, is the setting on the timming around 38? I guess the heating problem is the number one thing to take care of at this point. Maybe with the water pump modification on the plug and a change over to 180 thermostat will get this motor back to normal temp.  You mentioned the oil cooler. How does that work? Is this something that I can get from Jegs? I sure appreaciate the imput. I will check back once i get across the pond. Thanks  

You can do both, but I recomend tapping the block a pluging it. Don't forget to put a bypass kit on the t-stat housing or drill the .080 holes in the t-stat itself. I recomend the kit from jegs or summit.

Bad or wrong timing can also make you motor run hotter. Your total time should be around 38 deg. Thats a good start. That needs to be done at 3000 to 3400 rpms with vacume off. Your 18 deg. is probly your stadic time meanning at idle.

Yes the oil cooler. That cools the oil coming out of the oil pump to your oil filter to a cooler that acts as a rad. to cool down the hot oil before the oil goes back into the motor. Mostly trucks use then due to hauling which jenerats heat. By putting a fan on it will cool the oil down faster. (Yes you can get that out of jegs or summit)  

I made it home to work on the 383. Here is what's going on with it. I changed the thermostat to a 180. Changed out the clutch fan. I wanted to try the easy things first. I have the temp down to around 200 at idle as it will drop once it is moving. I will run it that way to see what happens. Now,,,,the 750 Holley is on. I set the carb as specified. I went back to the timing and set it at static, 38. I went in and changed out the springs in the distributor to a mid size. Now I am getting a bog. I tried to power break it to see where the power is as it falls on it's face. Once I drove it down the road, it just does not have the power it should have. When I had the edelbrock on it, power breaking it would smoke the tires. Would it be possible that the 750 may be to much of a carb? I was thinking of someting. When I had the car cranked up to 3 grand to set the static timing, the mark some what moved around at first before it stablelized. Could the distributor be a problem? I have the HEI distributor in the car with a MSD electronic module. The centrifugal weights seemed to move easy. Any idea what to do next? Thanks  

I don't think you set the timeing right. Did you set the total time at 38 deg. with the engine at 3000 rpms. Does your hei have a vac. advance. If so did you disconect it be for setting the total time. If conected the timing will not read properly. and at idle you should be getting a much lower Timeing reading.  

750 holley doublepump, Is a common used carb for a 383