Can someone tell me?

[Carmine]

Well, here I sit in the frozen tundra of the northeast with alot of time on my hands. I have a question that I've always wondered about and I think I'll ask it. Why is it that on a hot summer day, in my C-6 Corvette, with the a.c. on, in bumper to bumper, stop and go traffic, my temp. guage never moves from normal. Doesn't even come close to running hot or overheating. Now, if I was to try this with one of my trifives, it wouldn't be pretty. A few times I have had to pull off for a short time because the temp. was creeping up there. Has that much technology changed over the years? Also, if the temp. does start to creep up, is it better to bring the motor up to a higher steady idle or not? Thank you, Carmine.

[acardon]

I'm running a 671 BDS blower in my '57 Belair.

Might have something to do with it, especially if your runing a stock cooling system designed for 162 horse power engine. :happy0030:

[Kiwi56]

Carmine
Technology has changed
BUT
your trifives should do the same !
what is the set up ?
engine sizes ?
what fans do you have/use ?
shrouds ?
thermostats working correctly...or in there at all ?
correct pressure rating on your radiator caps ?
lots of variables :confused0006:

[557B210]

Carmine....My stock 265 with a stock cooling system does not overheat on the hottest days in Florida.

Now throw a 350 in there with a little HP and more than likely you'll have to upgrade the cooling system to match.

[Rick_L]

If you put the following on a 55-57, it will have temperature control just like your Corvette:

1. A big crossflow radiator, 16-1/2" tall x 27" wide core (like a PRC).
2. A correspondingly big electric fan setup, like a dual 11" or bigger, with proper controls for turning it on and off, including a trinary switch for the a/c. Maybe a dual setpoint setup so that when the temperature is high but not real high, it only runs one fan or runs both at half speed.
3. Good timing control, no excessively retarded ignition timing.
4. EFI makes it better yet.

There are intermediate solutions too, like clutch fans (more blades help), shrouds, etc.

[Carmine]

Well, here I sit in the frozen tundra of the northeast with alot of time on my hands. I have a question that I've always wondered about and I think I'll ask it. Why is it that on a hot summer day, in my C-6 Corvette, with the a.c. on, in bumper to bumper, stop and go traffic, my temp. guage never moves from normal. Doesn't even come close to running hot or overheating. Now, if I was to try this with one of my trifives, it wouldn't be pretty. A few times I have had to pull off for a short time because the temp. was creeping up there. Has that much technology changed over the years? Also, if the temp. does start to creep up, is it better to bring the motor up to a higher steady idle or not? Thank you, Carmine.

Many thanx to all who responded. My '57 Belair has a 406 sbc with a 671 BDS blower. The thermostat is a highflow 180 degree, initial timing is about 14 degrees, 4 blade steel fan, aftermarket aluminum radiator, 8-1 compression and I'm only pushing about 5 lbs. of boost, 400 turbo trans., 3.42:1 ring/pinion the temp. sending unit is in the head by the combustion chamber.
I really love this car and it brings me alot of joy when I drive it. It will run all day long 40-45 mph at about 190 degrees. Slower speeds, long stop lights, bumper to bumper, I can watch the needle rise. I've seen it at 240 and pulled off the road. I'm self taught with most of this and I don't know what to try next. I try to plan my course/route to avoid problems but sometimes it can't be helped. As the car warms up, I see the temp. climb to about 210 and then drops quickly to 180. Is this the proper opening procedure for the thermostat? Real dumb question, but with 190 degree reading in the head, if the sending unit was in the intake, would this be the same reading? Thank you, Carmine

[Rick_L]

"4 blade steel fan"

From your description, you need more air flow. The 4 blade fan has to go.

With your blower, I don't know what your fan clearance options are. Consider dual 11" or bigger electric fans. I think the problem will clear up quickly. Thing about electric fans, when your engine is running at idle or low speed, the fan(s) are running hard if they are on. Not so with a mechanical fan.

It's amazing the thing does as well as it does.

[Carmine]

"4 blade steel fan"

From your description, you need more air flow. The 4 blade fan has to go.

With your blower, I don't know what your fan clearance options are. Consider dual 11" or bigger electric fans. I think the problem will clear up quickly. Thing about electric fans, when your engine is running at idle or low speed, the fan(s) are running hard if they are on. Not so with a mechanical fan.

It's amazing the thing does as well as it does.

Thanks Rick L. You are not the first one to recommend a fan change. Others have told me the same thing; ditch that 4 blade fan. This was the original fan on the 283 and I guess I'm just a sucker for nostalgic things. I really did want to use it but not at the expense of the motor running hot. I'm not sure how much space I have but I'm definitely going to do something different. If I can fit the electric fans, that will be the way to go. Guess I'll just hang up that 4 blade in the garage and look at it for therapy purposes :) Thanx again to you and the others, Carmine.

[hqtrqd55]

I once heard from a really smart gm man that the newer cars with factory temp gauges basically tell us what we want to see. The manufacturer pads the reading a bit . The newer cars actually run hotter (it has something to do with emission) than what we would feel comfortable with so they make the gauge tell us something acceptable to us. That is why your vette doesnt creep up in temp on the gauge even though it may in actuality. I cannot promise this is totally accurate info but that gm man has proven me wrong on many occasions. :bowtieb:

[56owner]

I agree with hotrod that newer temperature gages are lying to us . We must have heard the same thing from different sources. If you'd put a acurate gage in a new car you'd drive it back to the dealership and tell them to fix it. :anim_25:

[dnsdoor]

carmine i switched to the electric fan temp dropped 40 degrees im not kidding you i could not believe the diff

[Rick_L]

Even if it's wrong, why is it so steady if the cooling system is inadequate?

My 09 GMC runs at 210 degrees once it's warm. I see no problem with that. Never goes past. It's never boiled, nothing.

My 95 Chevy was similar, except it had a mechanical fan and thermal clutch. The gauge was not marked, but it always stayed at whatever it leveled at.

Previous vehicles did not do that.

[Carmine]

Thanks again to everyone. I do believe I have to concentrate on the fan first. I'll see where that takes me. I might be back :), Carmine.

[jwmbishop]

Make that a third on the newer temp guages - the sender sends the data to the ecm and the ecm tells the guage what to say. So if there is a reason for it to run hot (such as a hard accel up a hill with ac on) the ecu can "filter" the guages reading so as not to alarm the driver. Its when the condition of cause is not there while the condition of effect IS (for a period of time) that the guage will show the increase.

Scary. Especially because the oil guage is under the same thing - Dodges are notorious for that! My friends 318 Ram was showing good pressure at idle - yet knocking when he tapped the gas (indicative of mains) so we added a mechanical and saw 8 psi at idle!