old muscle cars and summer heat...

[427dart]

If you were to take any muscle car of say 1969-1970 brand new and drive in todays world in the summer would it overheat in traffic/cruising?
Now the one reference point I have was my brother's 1970 Hemicuda with Super Track Pac which was the 4.10 gear and HD cooling system.
Thru 1970-74 when it was on the road it NEVER had an overheating issue in the summer.
In late '71 when we added the Race Hemi parts along with a smaller 6 cyl radiator and still retaining the factory clutch fan...never had any heating issues while cruising the blvds. in the Summer.
Could the E10 pump gas be at fault?
I had a new 1974 Z/28 Camaro L-82 350 and never had overheating issues with it's lower 9.5 compression but running still leaded fuel.
Also had a new 1977 Pontiac LeMans Can Am with the 6.6 T/A Pontiac engine and never any heat issues with it's low 8.2 to 1 compression on Unleaded fuel of that time.

[travis]

I think a lot of that would depend on what/where your driving. I had to go to downtown Dallas many years ago and the only vehicle I had was my ‘83 ford truck with a C-6 trans and 3.55 gears, and a very tired 351w. The poor thing had its tongue hanging out trying to keep up with the 85+ mph traffic. I couldn’t imagine doing those speeds for long durations with 4.10’s and no overdrive in 105* temps.

Now someplace like Atlanta, where the max speed limit is 55, I don’t think you would have any problems. Here in Texas, speed limits are merely a suggestion

[hoodeng]

When cars were new in the late 60's early 70's i would say the majority were produced with adequate cooling systems and head lights,even in 40°+ outback Australia your Falcon,Valiant or Kingswood V8 did not overheat to a major extent {you could also see a fair distance with the headlights of the day} air conditioning was not common. Mind you i think driving to the conditions was something drummed into every new driver then,if the temp gauge was creeping,back off a bit. Restore and run one today and weather is a consideration even after de scaling and new cooling systems. English cars here were another matter.

Is it the fuel? i don't think so, as an engine only produces the power it needs to overcome the load placed on it, so if it has to make say 50HP to cruise at 70MPH,it makes around somewhere in the vicinity of 30 to 50% of extra heat to be rejected, pretty much the same in its new days, the margin given to cooling systems in the day was worst case scenario ,manufacturers tested to death in the conditions that would dish up the worst outcomes,,,,then sold the car.
I can remember driving in the bush on red hot days in Bedford S and TJ series petrol trucks that had bare metal fire walls and cabs that were liner less even the roof was stupid hot, the motors didn't miss a beat,although a fuel stop could result in a vapor lock [which didn't hold you up anyway as you were expecting it].

An interesting point in a 'Detroit Series 53 Service manual ' is that If a 1" thick section of cast iron has 1/16" of mineral deposit on it, it has the same heat transferability as a 4 1/2" thick section of cast iron.
Years ago when i was still involved with machine and vehicle maintenance we started to get cooling systems professionally flow tested by a cooling system specialist company,what was found was there were deficiency's sometimes built in sometimes created that could explain vehicles that ran hotter than the norm.Pretty much all of them could be rectified.

Cheers.

[Dave Koehler]

If you were to take any muscle car of say 1969-1970 brand new and drive in todays world in the summer would it overheat in traffic/cruising?
Now the one reference point I have was my brother's 1970 Hemicuda with Super Track Pac which was the 4.10 gear and HD cooling system.
Thru 1970-74 when it was on the road it NEVER had an overheating issue in the summer.
In late '71 when we added the Race Hemi parts along with a smaller 6 cyl radiator and still retaining the factory clutch fan...never had any heating issues while cruising the blvds. in the Summer.
Could the E10 pump gas be at fault?
I had a new 1974 Z/28 Camaro L-82 350 and never had overheating issues with it's lower 9.5 compression but running still leaded fuel.
Also had a new 1977 Pontiac LeMans Can Am with the 6.6 T/A Pontiac engine and never any heat issues with it's low 8.2 to 1 compression on Unleaded fuel of that time.

Did I miss something? Are you now having issues with the same cars listed? or just doing a what if?

[lefty o]

imo , most of them will do just fine. most of them start having problems when people start adding flex fans, tossing fan shrouds in the trash etc. as mentioned above condition of the cooling system has a bunch to do with them keeping their cool, add in scale and corrosion, and they cant do their job.

[GARY C]

If you have a proper cooling system and tune I don't think it would matter what you drive, I have had both stock and performance stuff that worked and some that over heated.

Many git rid of the clutch fan thinking they are going to pick up big power with an electric fan but few aftermarket electric fans are capable of the job at hand.

[GARY C]

imo , most of them will do just fine. most of them start having problems when people start adding flex fans, tossing fan shrouds in the trash etc. as mentioned above condition of the cooling system has a bunch to do with them keeping their cool, add in scale and corrosion, and they cant do their job.

True That! Even where the fan is placed in the shroud can be the difference of working and not.

[chevyfreak]

like mentioned fans and shrouds, that gets changed or dumped. There is also alot more cars on the road compared to then. So slower moving traffic at various intervals.

On my cars i use solid fans. Mostly the gm clutch type with a clutch eliminator Where i can and Works very well And a electric unit in front that gets switched on in heavy traffic if needed.
On my one car that i do have a flexfan on due to size constraints i need to switch the electric on earlier but It helpes a great amout.

Chevyfreak.

[427dart]

On my 85 Mustang LX with the 427W I run the factory 17 inch plastic 9 blade fan with the Police clutch. Also have a 12 inch pusher fan
down in front of the radiator for use if needed in a traffic delay or extended idle in hot weather. It all works fine at keeping it below 190.
Now I had tried a HD fan clutch I think was a truck piece but high rpm during occasional full WOT would cause fan blade cracks at base of blade.
Got to watch fan RPM with the stiffer clutches.

[Fireonthemountain]

Drive the same old cars new off the dealers lots today and they would be fine, but old cars are old cars regardless of any new paint.

Then most have been tinkered with the trick of the moment over he decades, which is not the same tune or build the factory used.

For good cooling now a days I would recommend using a vacuum canister distributor hooked up to manifold vacuum, and not the ported vacuum port. Much cooler running especially around town in stop and go traffic. I would also recommend the largest new aluminum radiator that can fit in there. Then the carbs probably need to be taken off and clean thoroughly, to make sure as much gas as they were designed to flow still is. Next you might want to check the exhaust system to make sure it is still flowing fine and not partially getting blocked over time. A high pressure radiator cap also helps and an overflow tank. Antifreeze keeps them from corroding as fast and freezing but too much is bad for cooling.

[Roundybout]

I don't know how much difference there is between ethylene coolant and propylene coolant in heat transfer and viscosity but I believe ethylene would be more suited but of course more toxic so we've moved away from it. That could be one instance were the difference between running hot and over heating could occur in a borderline situation.

[Truckedup]

The only new car I had was 69 Dodge SB 383/335 4 speed.. It had the standard roundish top radiator and regular fan...In summer traffic jams going to the Jersey Shore it would heat up, the gauge would be on the high side but it never boiled over..When driving at 60 mph the gauge was reading lower...I sold it and bought a 69 Chevelle 396/350 4 speed. it had the heavy duty radiator and a 6 or 7 blade clutch fan...it also ran hot in the summer, in traffic or down the road the Sun temperature gauge was 200-210....Never seemed to hurt it...

[jake197000]

big cities had big traffic jams in the 60's did they overheat then ? i dont know but would think the were designed to operate in all conditions unless they were way extreme or overloaded

[jake197000]

pure water is the best coolant but not possible in cold climates

[jake197000]

with a rust inhibitor