runnin a lil hot

[chilwil86]

Bought a new gm crate engine all stock except intake and 500cfm performer, Runnin a hot in traffic 210 215 with fan goin. have the restrictor plate in place of thermostat,runnin the middle sized hole.New th350 too dont know if that will cause a problem.

 

[Northstar T]

Bought a new gm crate engine all stock except intake and 500cfm performer, Runnin a hot in traffic 210 215 with fan goin. have the restrictor plate in place of thermostat,runnin the middle sized hole.New th350 too dont know if that will cause a problem.

what's the temp run at cruising speeds? if it's ok at speed then you need more air flow through the radiator. a bigger fan, install a fan shroud, etc. In rare cases they are benificial, but as a rule I'm not a fan of restrictors in place of thermostats. what's your base timing with vacuum plugged?

Russ

 

[Golly]

Yep check the obvious first , Is it running lean for some reason. vacuum leak, retarded timing, carb running too lean etc. See if you can borrow an infrared temp gun and see what the actual temp is coming out of the motor as you may find the engine is just creating too much heat for the cooling system to handle. If that's Ok , then as Northstar T says you need to work out if it's an airflow problem or something in the cooling system itself.

 

[Wild Mango]

I don't like restrictors in place of thermostats in a street engine. Three reasons, 1/ Warm up is a lot quicker with a thermostat, and the sooner we hit operating temp. the better 2/ Engine temperature is far more constant with a thermostat in a street drive situation 3/ Thermostat interrrupts flow through the cooling circuit and gives coolant a lot more "radiator time" during which heat can be dumped. Effectively this creates a reservoir of relatively cool coolant under light load conditions the engine can use in times of heavier loads, like when the right foot has the pedal up against the firewall.
As usual, JMHO.

 

[chilwil86]

When its on the highway it'll run 180-190 just when it gets in traffic it gets hot.I'm gonna throw a stat in it just for kicks.I'm hopin to get some miles on the new crate and getter broke in.It's got 3.00 gear in it so it doesnt turn a lot of r's. gonna check all of the above.

 

[PotvinGuy]

1) check timing. 15 initial, 15 vacuum, 15 speed is a good start point. Number one cause of overheating is retarded timing.
2) 210 or 215 is not that hot. My crate SBC, 750 carb and 250 blower, runs 230 all summer. I disconnected the fans once and let it boil over to see how much headroom I had; it went to about 260 before it took off, so I know I'm OK.

 

[Wild Mango]

What Potvin Guy said.

One other thing to add into the mix, is that the majority of automotive instruments are not accurate. As usual, some are better than others. What I have always done is put in a new T'stat, say a 180F one and then after a good run note what the temperature gauge is saying. + or - 5F is as close as you can ever expect, usually its a bit more. T'stats are surprisingly set point accurate once everything has stabilised after the warm up.The important thing is, that the engine temperature is CONSTANT, that's the goal we strive for.

 

[blownt]

210-215 is not hot if you have anything higher than a 7lb radiator cap. I run a restrictor and have for 15 years. But here in Houston I ain't worried about it being too cold. Criusing in the evenings I run 185-195. Hottest in the afternoons it gets up to 210, but usually around 205.

PLEASE SEND RAIN. It's that clear liquid stuff that falls out of the sky, ain't it?

 

[railroad]

From your description, 180-190* on the hiway and 200+ while stopped, the advise about moving more air at idle is the easy solution.
While not the fix for overheating, I would recommend adding water wetter or equiv and running a good zddp oil or additive.

 

[Ted Brown]

Another thing to check, is what size water pump pulley are you running? I use the early small pulley on mine, runs faster and moves more water and air if you are running a stock fan, AC fan blades are a bit too noisy for me, but they work great if you are not winding too high... I don't run any Tstst in mine. They are made to great heat to dissipate water from the oil and keep the clean air folks happy, I know, you will say heat makes HP, that's fine with good fuel

 

[Screaming Metal]

Hahaha.....we were running a motor in on the dyno, and I was watching the water temp creep up as I raised the throttle, brought her up to 75%, I looked around at one of my guys and asked if he was sure he put the head gaskets on, as we were approaching 8500 and the temp was slowing some when it about 235.......I shut her down.
Partially plugged cooling passage in the head.....

Don't trust gauges....they aren't 100% accurate. Trust a heat gun.....they have come down in price enough that anyone serious about performance ought to have one. Thats like setting the idle with a tach......I use my feel, its whatever the motor is wanting, they're all different. Some like more rpm than others, some will normally run hotter than others.



210-215 isn't all that hot......if thats in traffic and never goes over 210-215, I'd say your good. You can always go with the non-water coolants and drop it some. Are you running a shroud? If not your fan needs to be within 2 inches. Are you running a flex fan or metal? Electric? If electric, are you pushing or pulling? What PSI cap? Whats your Thermostat temp? 195? Like Teds asked, what size pulley? All these have a bearing on your temp. What radiator you have?
Is it new? How many rows? Has it been flushed recently? How tight is your converter? Whats your idle rpms?

 

[Mike]

I use my feel, its whatever the motor is wanting, they're all different.

And you know, that really is the bottom line. What makes one motor happy might not generally won't work on the one right next to it.

 

[Screaming Metal]

And you know, that really is the bottom line. What makes one motor happy might not generally won't work on the one right next to it.

Mike, you are THE MAN!
:thumb: