How hot should the engine be?
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From: San Antonio, TX
How hot should the engine be? Whats the normal operating temp for an old school sbc? Mine usually runs@ 180-190 but it runs bad at that temp. It got up to 210* the other day and it ran great. I have been driving it with no thermostat lately b/c the old one went bad. So now that I have to get one what temp shouldI get? A 180* or a 195*?
you are right at the correct temp, 180 is great for the engine, 220 is too hot for a carbureted engine, I would not run anything hotter than a 180, MYSELF I live in texas, I would run a 160. The fact that the car ran better at that temp is leading me to believe it is probably out of tune, Timing is my first hunch, maybe a idle air mixture issue, it should not run noticably better when it is hot. Fuel injection engines are engineered to run at higher temps, but the carbed engines only need to be between the 170-195 from what I have always learned. Hope this helps a little.
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From: Tulsa, OK
You're playing with fire, and could be over heating your engine and not know it. With no tstat, the coolant can't stay in contact with the engines components long enough to remove heat. Temp range doesn't matter that much, that you have one does. Were it me, I'd do the 180, and sooner rather than later.
i've run 160s in both my thirdgens, they have always run fine, usually overheated with the 195*. 104* today outside and the drive home i topped 200* in neighborhood traffic. direct drive fan, no clutch.
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From: knoxville tn
stock usually has a 195 t stat. and usually run around 210. they say it helps reduce wear on cylinder walls. but for power i use the 160. i can get it. 210 or even 230 is not that hot. 260 is when you should start worrying. the electric water pump stopped working on mine one day and it hit 300. ran the engine 2 more years untill i sold it. never had a problem.
a buddy of mine borrowed my car and made it about 35 miles with the cooling fan off on the interstate...got hot enough to blow the upper radiator hose in half and the motor seized. still got the motor in the car, and now its getting hit with the bottle. poor old 305...
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Verdad Gallardo TECH Addict
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From: Tulsa, OK
a buddy of mine borrowed my car and made it about 35 miles with the cooling fan off on the interstate...got hot enough to blow the upper radiator hose in half and the motor seized. still got the motor in the car, and now its getting hit with the bottle. poor old 305...
I run a 195 thermostat on my 383, with aluminum heads.
Your running W.P. sportsman heads right? (Sig line) Since these are Iron, I would run a 180 t-stat. Iron heads should be cooler, because they don't disapate heat as well as Aluminum heads.
Running a 195 would be fine, but there is not point to it.
Your running W.P. sportsman heads right? (Sig line) Since these are Iron, I would run a 180 t-stat. Iron heads should be cooler, because they don't disapate heat as well as Aluminum heads.
Running a 195 would be fine, but there is not point to it.
180* or lower. Texas is pretty unforgiving. Run all your air dams, even the ones in the bumper by the washer resevior. If you are still running the stock LTx fans with your Gen 1 then make sure they are programed either way.
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From: San Antonio, TX
I think Im going to go with the 180* simply b/c im scared of it overheating too easily. I have removed the washer bottle and I have no condenser so all the air goes straight to the rad. The only thing is that its the one out of my third gen so its pretty freakin old but it does the job pretty good.
I used to have a 160*(the one that went bad) and the angine ran at 190* durin the day and right at 160* at night.
I think the reason why it ran better when hot is maybe due to having the wrong spark plugs. World recommends using Accel 276 plugs but due to lack of funds I used AC delco R45T.
When the engine was @ around 180 it would sputter at the top end and when it got warm it ran perfect all the way up to 6K
Thanks for all the replies BTW
I used to have a 160*(the one that went bad) and the angine ran at 190* durin the day and right at 160* at night.
I think the reason why it ran better when hot is maybe due to having the wrong spark plugs. World recommends using Accel 276 plugs but due to lack of funds I used AC delco R45T.
When the engine was @ around 180 it would sputter at the top end and when it got warm it ran perfect all the way up to 6K
Thanks for all the replies BTW
On The Tree
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From: Central NJ
I had a 160 in the 350 in my 84 Camaro - ran ok, but never really heated up to the proper temp. I changed it to a 180 and had my electric fans come on at 200 and 210, which made the car put out more power. As as been said before, most engines make max power with water temps ar 200 to 200, but intake air temps at ambient. Obviously injected motors with long metal intake tracts have other issues with the intake air temps...
what also has to be taken into consideration is where you live. i don't know about nj but down here in tx we're coming off a 5 day straight of over 100*. then compound that with sitting in traffic and no airflow except the fans(which aren't really adequate) and then the 160 thermostat looks good. btw today was 92* i think and you could feel the difference in temps though.
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you are right at the correct temp, 180 is great for the engine, 220 is too hot for a carbureted engine, I would not run anything hotter than a 180, MYSELF I live in texas, I would run a 160. The fact that the car ran better at that temp is leading me to believe it is probably out of tune, Timing is my first hunch, maybe a idle air mixture issue, it should not run noticably better when it is hot. Fuel injection engines are engineered to run at higher temps, but the carbed engines only need to be between the 170-195 from what I have always learned. Hope this helps a little.
Might be a long shot, but compare the two plugs.
I know I used to always run ac delco acr45ts plugs in my iron heads. when I got my aluminum ones, I disregared the "instructions" which said the use Plug "X".
The acr45ts plugs thread shank was way to short, the electrode was not even close to the bottom of the hole.
May be something to check, Go the a local parts house and compare the 2. See if what they recomend is a longer plug.
I know I used to always run ac delco acr45ts plugs in my iron heads. when I got my aluminum ones, I disregared the "instructions" which said the use Plug "X".
The acr45ts plugs thread shank was way to short, the electrode was not even close to the bottom of the hole.
May be something to check, Go the a local parts house and compare the 2. See if what they recomend is a longer plug.
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From: San Antonio, TX
Might be a long shot, but compare the two plugs.
I know I used to always run ac delco acr45ts plugs in my iron heads. when I got my aluminum ones, I disregared the "instructions" which said the use Plug "X".
The acr45ts plugs thread shank was way to short, the electrode was not even close to the bottom of the hole.
May be something to check, Go the a local parts house and compare the 2. See if what they recomend is a longer plug.
I know I used to always run ac delco acr45ts plugs in my iron heads. when I got my aluminum ones, I disregared the "instructions" which said the use Plug "X".
The acr45ts plugs thread shank was way to short, the electrode was not even close to the bottom of the hole.
May be something to check, Go the a local parts house and compare the 2. See if what they recomend is a longer plug.
If I were you, I would try to find some spec on your heads. Figure out how deep the spark plug thread hole is. Or if your creative figure some way to measure the depth with something.
If you have a speed shop near, see if they have the same heads in stock. Then ask If you can try different plug in the head, therefore letting you Phyically see how deep they are seating.
Then spend a little bit at whichever parts house your "friends" with, pulling different plugs. If your like me, You know most the people inside by first name. haha
When I built my 383 I physically brought my heads up with me, then tried different plugs until I found the one that worked best. Which turned out to be factory LT1 spark plugs.
If you have a speed shop near, see if they have the same heads in stock. Then ask If you can try different plug in the head, therefore letting you Phyically see how deep they are seating.
Then spend a little bit at whichever parts house your "friends" with, pulling different plugs. If your like me, You know most the people inside by first name. haha
When I built my 383 I physically brought my heads up with me, then tried different plugs until I found the one that worked best. Which turned out to be factory LT1 spark plugs.