350 SBC -- How Hot is Too Hot?

Howdy!

I finally got my buick inspected and registered today, so I'm all set for the Roundup!

However, it seems to be getting too warm (or maybe I'm just being ****).......

Brand new scoggin ****ey goodwrench 350, 290 horse, aluminum pistons, 180 degree thermostat.

It's only been in the low 80's here, and at a red light she's heating up to about 190. No big deal right? But it gets up over 100 here in the summers - so.....how hot can I let this particular motor get before I need to worry about causing damage?

Also, I'm running a 16lb radiator cap too.....is that appropriate? It spits just a little when I kill it and it's hot (just running an overflow tube, not a recovery tank).

Have a 19" fan and a 20" shroud (about 1/3 of the fan is in the shroud and 2/3 is outside).

Is the fact that it's heating up 10 degrees when it's 80 degrees outside indicative of overheating in 100 degree weather?

Should I worry? What else can I do to keep 'er cool?

Muchas Gracias,

Heckler

 

If it stays under 210 and isn't leaving puddles after trips I've always been good with that but to each their own.

 

shouldn't be an issue. remember, the thermostat and/or the gauge could easily be inaccurate. With a good cap, 230 shouldn't be an issue, but 210 sounds better. Drive it like you stole it

 

Put a recovery tank system on it if you can. Just get something from the junk yard. Whatever it pukes up, go back in as it cools down.

 

If you want some peace of mind, install a small pusher fan in the front and wire it through a toggle. I was running warm in traffic last year at the Roundup, so I grabbed a $20 12" fan from one of the vendors. I wired it up with some extra wires, etc. in my toolbox and it bought me an additional 5-10 degrees in heavy traffic.

I rarely need it, but it's nice to have that little toggle switch on the dash when I need it.

With all that said, you're fine at 190. My thermostat on my SBF is 192 degrees and routinely reads 195-200 on my cheapo Moon temp gauge.

 

Should not be a problem, but if you are concerned drop a 160* stat in it. As the motor gets broke in it will run a little cooler as well....

 

190° isn't a problem but be sure to check your timing. Slow timing will cause an engine to overheat. You don't talk about your distributor but you probably need about 8° to 10° initial with 34° total all in by 3000rpm. These figures with vacuum advance disconnected and plugged. After setting reconnect advance.

 

this is a great thread im curious to see every ones opinion. i personally get nervous when my engine goes over 215. Usually if im parked some where in july or august waiting in line at a show etc. but it can be fraustrating. i by no means understand engines but am trying to learn.

 

You'll know it's too hot when it boils over. Otherwise anything under 220 is easy-cheesy. But realistically 240 won't hurt anything for short times as long as it's not boiling over and forming steam pockets. Boiling = bad

 

common scenario..... that said, trusting temps are only done by testing everything with a real (accurate) thermometer.

- first of all, before i install any thermostat i confirm the opening temp by watching it in a heating pan of water with an accurate thermometer.

- do the same thing with your gauge. put the sensor in a hot water pan and the same accurate thermometer. Vary the temperature of the water and see different temp points that the gauge is off.

it's realistic for typical car gauge to be +-10% off. That said, your motor could be warming to 180, the stat opens, and your gauge shows 190.

know what the temps really are. new commodity built (in many cases made in china) car **** can't be fully trusted. confirm and you'll know the real deal.

-scott noteboom

 

You will get a higher reading on the side of the head than you will up by the thermostat, and yes, put a puke tank on it, they work better with no air in the system.

 

With a 16 psi cap the system can not boil until the water gets p***ed 250 degrees,
So I don't think you need to worry none,
If anything higher temps equal better running and gas mileage.

Notebooms is far too kind to typical dash gauge, most tell random lies, never believe them, they are only a vague indication a best.

 

Check your vacuum to the distributor--ported will make you run hot at idle, Manifold vacuum runs cooler-Do a search for post by CX9

 

Great points above about gauge accuracy and sender placement. But if you have quality modern aftermarket gauges installed properly, they outta be real real close.

I have friends that watch gauges like a hawk and freak out about the tiniest thing. Know what really gets under their skin? Me asking what they're gonna do about it. Unless you got a full effort race car, gauges are like a forest-thru-the trees thing. You're looking for trends and you're looking for changes to the trends. They're not the gospel by any means. Frankly I wish street car gauges could slide under the dash, outta sight, and only be used for break-in and troubleshooting.

Another sign you should be concerned? Pinging under load and dead spots in the throttle that don't exist at lower temps.

Your 190 temp is not concerning. However, back to forest thru trees......if that 190 is indicitive of constant temperature creep at idle......and 190 just happens to be how hot a light cycle gets it.......and it'd go to 250 if you had to sit another 15 minutes......that's bad.

good luck

 

You really need to ****yze more than a single point temp, also. To further Shifty's point, if you just look down at the guage, you don't know much. Imagine you can have a register tape coming out of that temp guage with a wavy EKG kind of line on it. What does the temp cycle look like through an hour of routine driving?

I had a TBI small block in a *****y little OT pickup once. Radiator was application appropriate, fan was temp controlled electric and T-stat was 190* (EFI thermostats are intended to create a ~210* average temp). This truck would have a tape that looked like a really slow heart beat. It would slowly ramp up to about 225*, stat is wide open, fans would kick in and the pulse would drop to 185*, fan would shut off and cycle would repeat. It ran like that in any traffic, any time of year, and loading, always. To be that stable in the bigger picture, it must have cooling reserve capacity in the btu dissipation of the radiator(and fan), adequate coolant circulation capacity and a means of control(T-stat). If you have all those match ingredients, you will be fine. If you have these elements and the temp goes out of control now and then, you need to look at timing and control of the elements.
Flex fans without a fan clutch are counter productive because they cool too much at lower speeds. A fan clutch adjusts it's output to operating temps like an electric fan with a good controller. Leaving a thermostat out creates a cascade effect that can run out of control if cooling capacity of the radiator core is not high enough to compensate for coolant that moves through too fast. A missing fan shroud will make a fan ineffective in an otherwise well designed system. None of this is new ideas, we just all have a habit of looking at a single piece of a larger puzzle. Food for thought.

 

I always use a 160 degree thermostat, 7 pound cap, 12 degrees initial, 34 total timing, recovery tank, mechanical fan. A general rule is that engine temp should be 100 degrees above ambient. As stated above, thermostat and temp gauge should be checked for accuracy. The FOGGER

 

Heckler I've looked at the picture of your car and think you should dump it, thats right, get rid of it now.I'll give 5,000.for it..kidding a side the puke after you shut it off could be expansion in your radiator the water will level off after it pukes a few times just don't top it off..Good Luck.....