running hot.....really hot
 

79 body with a new crate motor. SBC 350/400 nothing too big, and mortor runs real smoothe.

new radiator, new hoses, new cap (dunno lbs), fresh prestone 50/50, water wetter, seven blade fan, electric fan kicks on at 190.
both heater hoses are hot and the same temp, no leaks, no weird noises, 4 degree adv on timing, AC 45RT plugs, carb is edelbrock 600 at factory specs. Maybe too lean?

Radiator is full ! belts are tight, nothing slipping as far as I can tell

Any ideas on cooling both of us down will be appreciated.

RE: running hot.....really hot
 

Check the thermostat in a pan of boiling water to see if it opens fully. New ones have been known to be bad.

RE: running hot.....really hot
 

How hot is hot? I took mine out this week and it runs around 210

RE: running hot.....really hot
 

IMHO, if ya can keep 'er under 220 that's fine. I don't see aprob with 190 at all.

RE: running hot.....really hot
 

gigabyte,

Try punching out the thermostat thus giving a greater but restricted flow. This works good during the summer. You must replace for winter use. In order to get heat. If that doesn't work. Tell me if you have a belt driven fan or a electric.

RE: running hot.....really hot
 

One prob with that,....
The water needs to remain in the block long enough to pick up the heat. The water heat may drop off, but the engine it's self will get hotter. I don't suggest that you open up to free flow. [sm=nono.gif]

RE: running hot.....really hot
 

Hi gigabite, here's a few more things to check to cool down your "Hot Vette"
Do you have a "Spoiler" on the bottom of your car? That helps a let to direct the air up into the radiator.
Have you checked to see that all the seals around the radiator are there? They help to direct the air thru the radiator rather than let it pass by the sides and top.
You said you have a new radiator but did you change and install the proper cap?
How's the fan "Clutch"? A quick test is to let the engine idle and turn it off. A good clutch will stop the fan from spining in 1 or 2 seconds.
Timing: You didn't say what kind of distributor you have but 8* to 12* initial ( with vacuum can disconnect and pluged )might help.
At idle with the can connected you should have about 24* to 28* ( that's with a vacuum can that gives you 16*, not sure what yours is or does).
Than you should have a total of 48* with a max of 52* at 2800 RPM to 3000 RPM.
You can also change to a colder plug like AC 44 RT. I'm not sure about this one since I'm not sure how much heat one heat range plug adds, but maybe someone else will chime in.
One last thing, you don't have to drill out the thermostat, you can get a "Mr Gasket" #4364 at the auto parts store, they come with holes in them and if they fail they do so in the open position so some water passes thru them and the block dosen't crack.
Hope some of this is some help to you, PG.

RE: running hot.....really hot
 

The heat range on a spark plug relates to the temperature the tip runs at. A hotter plug means the tip will run hotter cuz the heat path to the block is longer than on a colder plug. I always run a hotter plug in mine to keep it clean since most of my driving is in the city.

I don't think the plug temp will have any effect on engine temp.

RE: running hot.....really hot
 

Hi 73shark, I never figired that the heat range of a plug had much difference on the engine temp since I've tried higher and lower and never saw any change on the temp guage.
The way I heard it, if you have a low compression, low HP motor ( as I do ) than a hotter plug would burn off some of the carbon build up, is that correct? PG.

RE: running hot.....really hot
 

When does it over heat, while shes running, in traffic, at idle, with the acon or all of the above??

RE: running hot.....really hot
 

I misunderstood you re: plug heat range vs engine operating temp.

That's why I went to a hotter plug cuz most of my driving is in town and it just burns cleaner.

RE: running hot.....really hot
 

Hey everyone thanks for answering up with all the info. I've been away for a few days and unable to answer all of you. The distrib is a Wysco. A friend came over and checked the timing and told me that the hole in the intake (edelbrock) is too big and most 3rd party intakes have a hole that is too big for the distributor. This one lets the distrib wobble some and needs a shim. (Jegs and Summit both carry a distributor shim kit) With a hole too big the hold down cannot be tightened enough to stop the wobble which in turn causes the timing to change. In this case it went from 8 BTC to 4 ATC which probably causes the overheating. It runs like a gazelle until it gets hot (220 plus) and then just about refuses to run at a stop light. It chugged about a half mile to the house.

The fan clutch is OK and she has the stock spoiler on the front. I did order a "high flow" 160 thermostat from summit to see if that helps.

thanks again guys for lending a thought

RE: running hot.....really hot
 

Be sure to let us know how it turns out w/ the new 'stat. :)

RE: running hot.....really hot
 

What kind of radiator do you have? I had a brand new 4 row brass and copper radiator that simply did not do the job. I switched over to an aluminum radiator (under $200.00 if you shop around) and my overheating issues were resolved.

[sm=icon_cheers.gif]

RE: running hot.....really hot
 

Hey DV8, where'd you get an aluminum radiator for $200, I may need one once I get my stroker transplanted.

RE: running hot.....really hot
 

Hi,

How close is you fuel line to the block or exhaust? It may be to close and getting hot causing vapor lock. Mine is also boiling the fuel in the bowls causing pressure spikes in the jetting. When you come off of a red light does it lurch forward and back like it is not getting enough fuel or bogging?

My 2 cents, hope it helps!

-Ross

RE: running hot.....really hot
 

I got mine from Southwest Speed
http://www.southwestspeed.com/?sec=view_menu&cat=Cooling%20System⊂=Radiato !rs&ssub=!Southwest%20Speed%20Radiators&ss sub=Chevy

If I remember right I got the 19" x 29" unit. It is not a direct fit - I had to modify the top radiator hold down slightly. I can get the info and some pics if you need them.

[sm=icon_cheers.gif]

RE: running hot.....really hot
 

Thanks for the info DV8, I'm running a new four row copper right now but may have to upgrade to aluminum, I'll have to see how it works once I change to the 383.

RE: running hot.....really hot
 

I understand that you need to use an anti-freeze condusive to use with an aluminum rad. It deals with corrosion issues. Electrolysis, etc.

RE: running hot.....really hot
 

A new high flow 160 degree thermo really helped with the cool down. The radiator is a new stock radiator I got from auto zone. The distro shims helped alot also. no more wobble. The fuel line is runnig about three inches from the block, up the front next to the h2o pump. I am concerned about heat there and bought a tube of thermo-flex from "cool-it", which should help. I am also thinking of putting in a alum radiator sometime.

Quote from my wife, "you are crazy putting all this money in an old car, you should have bought a new one." What do you think guys; should I go for it?

RE: running hot.....really hot
 

I'll take that 'old car' off your hands. ;)Then ya can go out and buy a brand new Vette. :)

RE: running hot.....really hot
 

Should you go for it - meaning a new Corvette? OF COURSE!!!!!! Especially if you have your wife's blessing.
Then there are those of us who love getting up close and personal with our old cars - you know the type - grease under the finger nails, skinned and greasy knuckles.....
Or you can really test the wife's patience and ask for both! [sm=badbadbad.gif]

[sm=icon_cheers.gif]