Engine temp on chevy small block

Rob_Roy said:
I don’t disagree with you on that, but this is clearly not the stock engine for this car. My experience with SBCs (especially ones with aftermarket cams) is that they do well with ported vacuum advance. Your mileage may vary - nothing wrong with trying it both ways (will need to adjust timing and carb accordingly, and see what drives best.
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If…if this distributor is set up correctly then manifold vacuum is best. During acceleration the mechanical advance takes over as vacuum drops with open throttle. More expense but If this engine has poor vacuum at idle due to performance cam then a programmable distributor that allows for a simulated advance at idle then a preset all in advance programmed at WOT. There are adjustable vacuum advance cans. LT-1 350 (1970) had one of the best factory distributors with a correct vacuum can and mechanical advance. (Nostalgia) it was manifold vacuum.
 
Carburetor1 said:
Nothing moved around the engine ran consistently when advanced timing. Will remove thermostat tonight and flush system again the water is looking a little rusty
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Can you give me clarity on your comment "nothing moved around" ?

Do you know what spark scatter is and how to diagnose it?

I specifically mean was the timing mark steady when revved and held to say 1500 rpm, 2000 rpm, 2500 RPM
and not jumping back and forth 2 -5 degrees.

Not trying to be snooty at all , just trying to assess the health of your timing system from 1000 miles away ;)
- Ken
 
wag123 said:
If you are getting a total of 20 degrees advance at idle (I assume this is what you meant when you said "Got vacuum up to 20") you need to adjust the vacuum advance pot to give you more advance. You need to aim for 22-24 degrees of advance at idle. How you do this is by inserting a small allen (hex key) wrench (I think that it is 3/32") into the vacuum port on the vacuum advance pot (if it is adjustable, most were in points ignition vehicles). If it doesn't have an adjustable vacuum advance pot you should obtain and install one.
If you get pinging when cruising in 4th gear at lower RPMs when trying to accelerate, you need to back-off on the static advance a little, and then compensate with a little more vacuum advance at idle (you still want 22-24 at idle).
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I read that as the vacuum level is up to 20, not the ignition advance.
 
The vacuum gauge read 20 when hooked up to carburetor originally it was a little above 15. There is no ping while driving and had noticeably more pick up in gears 3 and 4. The vacuum advance hooks into carburetor. Overall the car runs great now except for temp at idle, but it drops to 180 190 while driving. One thing is the heat soak if the car runs and ya shut it off sometimes it will take 10-15 min before it starts. Mabe that's the electric choke needing adjustment
 
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ARCOgraphite said:
Can you give me clarity on your comment "nothing moved around" ?

Do you know what spark scatter is and how to diagnose it?

I specifically mean was the timing mark steady when revved and held to say 1500 rpm, 2000 rpm, 2500 RPM
and not jumping back and forth 2 -5 degrees.

Not trying to be snooty at all , just trying to assess the health of your timing system from 1000 miles away ;)
- Ken
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The mark on the balancer didn't move from where it was set
 
Rob_Roy said:
Could be the choke, or vapor lock. I had a Camaro that would literally boil the fuel in the carburetor. I solved it with an insulating carb spacer.
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I have seen those.. so it's just because everything is hot and needs to vent a little basically?
 
PontiacHO said:
If…if this distributor is set up correctly then manifold vacuum is best. During acceleration the mechanical advance takes over as vacuum drops with open throttle. More expense but If this engine has poor vacuum at idle due to performance cam then a programmable distributor that allows for a simulated advance at idle then a preset all in advance programmed at WOT. There are adjustable vacuum advance cans. LT-1 350 (1970) had one of the best factory distributors with a correct vacuum can and mechanical advance. (Nostalgia) it was manifold vacuum.
Click to expand...
The fact that he is getting 20" of vacuum at idle tells me that the engine has a stock (or very near stock) cam.
 
Carburetor1 said:
The vacuum gauge read 20 when hooked up to carburetor originally it was a little above 15. There is no ping while driving and had noticeably more pick up in gears 3 and 4. The vacuum advance hooks into carburetor. Overall the car runs great now except for temp at idle, but it drops to 180 190 while driving. One thing is the heat soak if the car runs and ya shut it off sometimes it will take 10-15 min before it starts. Mabe that's the electric choke needing adjustment
Click to expand...
So, what does your total advance look like at idle? Are you getting 22-24 degrees?
 
Carburetor1 said:
The vacuum gauge read 20 when hooked up to carburetor originally it was a little above 15. There is no ping while driving and had noticeably more pick up in gears 3 and 4. The vacuum advance hooks into carburetor. Overall the car runs great now except for temp at idle, but it drops to 180 190 while driving. One thing is the heat soak if the car runs and ya shut it off sometimes it will take 10-15 min before it starts. Mabe that's the electric choke needing adjustment
Click to expand...
If your temp is holding steady at 210F when idling in warm/hot weather, and you are running a 50/50 antifreeze/water mix with a 10 psi radiator cap, the boiling point is 252F so you have a good safety margin before it actually overheats. Problem solved. BTW, a 15 psi radiator cap will give you a 267F boiling point.
If the hot engine is cranking and not starting I think that carburetor heat soak is causing your restart problem. You might want to consider installing a carburetor insulating spacer like Rob Roy recommended. If the hot engine won't crank you will need to back-off your static advance and increase your vacuum advance.
 
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wag123 said:
If your temp is holding steady at 210F when idling in warm/hot weather, and you are running a 50/50 antifreeze/water mix with a 10 psi radiator cap, the boiling point is 252F so you have a good safety margin before it actually overheats. Problem solved.
If the engine is cranking and not starting I think that carburetor heat soak is causing your restart problem. You might want to consider installing a carburetor insulating spacer like Rob Roy recommended.
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My radiator cap has a 7 in the middle on a button also have a chrome chevy cap with bigger spring in it but not sure on psi rating.and I'm looking into a spacer. I have a carb rebuilt kit and this winter it will be maintained so will prob install it then.
 
Carburetor1 said:
My radiator cap has a 7 in the middle on a button also have a chrome chevy cap with bigger spring in it but not sure on psi rating.and I'm looking into a spacer. I have a carb rebuilt kit and this winter it will be maintained so will prob install it then.
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The 7 on your radiator cap means that it is a 7 psi cap. That was common on Chevys back in the day. I would recommend getting a 10 or 12 psi cap.
 
wag123 said:
The 7 on your radiator cap means that it is a 7 psi cap. That was common on Chevys back in the day. I would recommend getting a 10 or 12 psi cap.
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Gotta watch that. If it's the original radiator it won't take more than 7 psi. Stock pressure back then was 4 psi. Adding 10-13 psi will blow the tank off the core
 
Chris142 said:
Gotta watch that. If it's the original radiator it won't take more than 7 psi. Stock pressure back then was 4 psi. Adding 10-13 psi will blow the tank off the core
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The reservoir was replaced with a tall chrome slim cylinder...Not original plastic reservoir
 
Chris142 said:
Gotta watch that. If it's the original radiator it won't take more than 7 psi. Stock pressure back then was 4 psi. Adding 10-13 psi will blow the tank off the core
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I have heard that warning, but I have never personally seen that happen, or know anyone that had that happen, at 10-12 psi. I do know a guy that had a heater core fail using a 15 psi cap.
 
Carburetor1 said:
The reservoir was replaced with a tall chrome slim cylinder...Not original plastic reservoir
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They didn't come from the factory with coolant overflow tanks/reservoirs in 56. Chevy did offer a cylindrical metal tank as a dealer accessory back then, but I never saw one.
 
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