Lowering under hood temperature

[Jayhawk851]

Hey all. So I’m beginning to have a problem with my truck and I’m not sure what to do. I have a gen vi 454 that’s been mildly built. Bored over .030 with higher compression pistons. I’m running 93 octane gas and the timing is at 12 degrees. On cooler days it runs perfect, but now that it’s been getting pretty hot where I’m at(90+ degrees) I’m having an issue with pinging sometimes on moderate acceleration. Normally the coolant temp runs about 195 and I have no issue. Now that it’s warmer the temp gets up to about 205 at time like when I’m sitting at a light, that’s when I’ll get the pinging. I’ve got the largest radiator that will fit with good dual electric fans, so I don’t believe the cooling system is the issue. Under the hood just gets VERY hot. I’m trying to think of a way to get some better airflow under the hood. It is a stock hood with no cowl, not sure if a cowl hood would help. Just trying to think of ways to get some better airflow under the hood to lower the temp. Thanks in advance.
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[Lee H]

I see your initial timing is 12, is that with vacuum? What is your total timing at what RPM? Do you ever get run on when you turn your truck off?

[72SB]

1. back off timing 2 degrees
2. get better EL fans

when truck is sitting at idle in traffic and starts to overheat, you don't have enough fan....assuming your radiator is in good shape

When ypu get ping under lad (detonation), you have to much timing

[Jayhawk851]

No run on. I have a champion 4 core radiator. Timing is without vacuum. I have not checked total timing. One of my cooling fans is making noise so I have some new ones ordered that should be here next week. More cfm than what I have now. I will also try backing down the timing 2 degrees
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[KQQL IT]

Look at your advance weight plate. Make sure it's free moving and no broken springs

[68 P.O.S.]

Try re-timing it, first setting total timing to 36 degrees with vacuum advance disconnected and plugged. Then check where your initial timing sits at as a mental note, but don't adjust it. Then reconnect the vacuum advance to manifold vacuum, if not already there. Reset the idle (750 for auto, 600 for manual). What temp thermostat and is it regular or hi flow? Is water pump regular or hi flow? How are the e-fans wired and where is the temp sender installed at? Which distributor is in it?

[Jayhawk851]

I believe it’s a 180 thermostat, just a standard one. Have a high flow water pump. Temp sensor is in the intake manifold. I run a fitech fuel injection that controls the fans to come on at 197. Same with idle speed. I think I have idle around 750. Pertronix flamethrower distributor with a Petronix ignition box I bought as a kit.
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[68 P.O.S.]

You need a high flow thermostat to match the water pump. Right now it's slowing the flow down. I don't know about the FiTech units, so can't really speak on how well they operate the fans. Have you looked to make sure the fans are activating at the set points? Does the FiTech control the timing as well?

[Jayhawk851]

Does not control timing. I I know that when the engine is cold the coolant temp is spot on. I’ll try to track down a high flow thermostat
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[Getter-Done]

Years ago, I had a 76 Blazer.
It had a built 454.

I went from a clutch fan to a set of electric fans.
It started running hotter.

So I put a pusher fan on the front of the radiator that I could control manually.
That solved my issue.

[my67c20]

An important but overlooked issue is the temperature of the air entering the intake. Just like a human that if your sucking in hot air, your body ain't gonna stay cool. While cold air intake benefits are heavily debated, there is some value in trying to get the intake air from a cooler source, even if that is an area lower under the hood.

[Jayhawk851]

So I have been looking into making a “cold air intake” for the motor. Get one of those carburetor hats with the 90 degree elbow and run pipe down to the front under the battery or the same spot on the drivers side
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[Willie Makeit]

Originally Posted by my67c20

An important but overlooked issue is the temperature of the air entering the intake. Just like a human that if your sucking in hot air, your body ain't gonna stay cool. While cold air intake benefits are heavily debated, there is some value in trying to get the intake air from a cooler source, even if that is an area lower under the hood.

the temp of the air entering the engine by way of the carb/throttle body has nothing to do with the coolant temperature.

does it effect fuel density? maybe - again debatable. coolant, no.

[Jayhawk851]

You are correct willie. It does not affect coolant temp. But the engine drawing in 100+ degree cooler air could definitely affect the way it runs. The motor isn’t overheating, I just get the pinging when the coolant temp gets around 205. I’ve noticed if it hangs around 195 I don’t get detonation. Idk if I need to draw cooler air to help the issue or try to get the under hood temp lower so it stays around 195
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[Rickjz]

I have a 1969 big block Corvette that I tried using an electric fan on. It had a hard time keeping the temperature down. Went back to the original clutch fan and I have no problem.

[72c20customcamper]

205 if the sensor is in the head isn’t hot at all my fans don’t kick in till 205 and cut out at 185 that with the sensor for them in the radiator the head temp will be around 215 . The pinging is timing

This is the 496 in my Chevelle

[jimijam00]

Originally Posted by Jayhawk851

So I have been looking into making a “cold air intake” for the motor. Get one of those carburetor hats with the 90 degree elbow and run pipe down to the front under the battery or the same spot on the drivers side
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https://www.summitracing.com/parts/spe-733

[Willie Makeit]

Originally Posted by Jayhawk851

You are correct willie. It does not affect coolant temp. But the engine drawing in 100+ degree cooler air could definitely affect the way it runs. The motor isn’t overheating, I just get the pinging when the coolant temp gets around 205. I’ve noticed if it hangs around 195 I don’t get detonation. Idk if I need to draw cooler air to help the issue or try to get the under hood temp lower so it stays around 195
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you got too much timing in it