Anyone have luck running without a thermostat?

Can running without a thermostat make your car run significantly cooler under normal driving conditions? I know alot of guys have said it makes it worse, since the coolant has no time to cool off in the radiator, but has it worked out well for anyone? Thanks,
-Dean

 

use a restrictor if you want to run with out a thermostat. its like a thermostat with just a hole in the middle of it to slow the coolant down enough. moroso makes those. i used one in my 1961 chevy. they work good.

 

I have a SBC in my very unHAMB friendly El Camino. I bypassed the heater core and have a restrictor in the housing. Its a 400+ horse engine with a lumpy hyd roller cam. I have a stock waterpump and a Griffen radiator.

The Camino never goes over 190* even stopped in traffic. On the highway in 90* heat its running 170* Hell, at the dragstrip I had to TRY to get some heat into it to get it warmed up. Still made the pass at 165* (12.71 @ 104 for those who care)

The truck has a cowl hood but it also has sheetmetal panels that hold in alot of heat.

It worked for me.

 

I have a hopped up sbc 350 w/high compression,I run a restrictor plate with a hole of 1/2 inch. It runs at about 180 when I do abuse it it runs 190-200. My brothers car is a mild mill his runs at 150- 160 all day long his has a 5/8 hole in it.

 

Just curuous but why run without one?
On a street driven car they just make sense, serve a purpose, and rarely cause any problems. Plus it costs like five bucks.

 

The engine is a supercharged 465-500hp sbc. We took it just around the block and it ran 185, then got up to 190, then maybe a tad bit more by the time we got back. Came back, shut it off and it went up to about 215 before coming back to 160, at which point we attempted a second run, but it was already up to temp by the end of the road. It just seems to be running a little too hot. It has a 6 blade flex fan about 5 inches from the radiator, which is a 4-core. The problem is one of the fan bolts is stripped and wont come out very easily to move it closer, so I was thinkign a shroud or no t-stat.
-Dean

 

you need a shroud for sure, i think

 

after having some heating issues (thermostat sticking or not working smoothly..) in my 61 biscayne....i pulled the thermostat out and put in a cutout ring.....car was going 210 within 5 miles....and throwing belts like a mother.....without the thermostat... it will stay under 150 driving around the house.....even in the 95+ degrees we've been having all summer.... brandon

 

It won't run cooler. It's just i don't trust them not to stick. So, I don't run them. No issues in 35+ years. This has been covered before, but restricting the flow of water is more a wives tale than anything. If the water runs through the system twice as fast without a stat, and only transfers 1/2 the heat, it does it TWICE as often resulting in a push, or a tie situation.

 

If this is a new setup and gauges you've never run, hit it with an IR gun on the radiator hose before you start changing things on the cooling system.

My vintage gauges are about 20 degrees off!!

 

I'd say aim the gun at the thermostat housing (unless it's chrome) for the best reading. If you want to check the accuracy of the gauge, aim the infrared as close to the temp sending unit itself.

 

I have heard that if you don't use a stat the front half of the engine runs cooler than the rear half, which causes faster cylinder wear on the front half. Don't know if that is true or not however.

 

WAY TOO FAR if no shroud!

 

Actually I'd be pretty happy with those numbers. Pretty close to normal IMHO.

The fan is too far away.

I'd run a 160 stat. I need to put a stat in my Stude motor. Summertime is ok but in the cool weather it won't heat up enough to run right. I'll need it soon. I'd think it would be worse with a huffer. It's actually harder on an engine to run it too cool than to run in the 190-200 deg range.

 

i poke the center out of thermostats all the time, just make sure you have something to restrict the flow or it will flow too quickly and you may run a little warm. hence the reason i just knock out the center.

 

With a street built SBC, having a thermostat is a necessity the minute it cools down below 60F degrees outside. Usually in the cases I've seen, the engine will pump enough liquid thru, but not restricting it will cause more cooling than is needed. You end up needing to choke the carbs, to run off idle at least. Black smoke? Fuel washed cylinder walls, due to too rich, or starved due to too lean? Why not keep the block at temp? I'd not chance it by running an open housing.

 

well i think 5 inches away from your radiator is a big issue..just my opinion..waanna make a bet with me that if you pulled that fan within 2 inches of that radiator and you could shroud it ,..betcha your temp would drop significantly..ask me how i know..

 

Seriously, run a shroud. We had an old beast of a BBF that we couldn't keep under 200 degrees until we put a shroud on it. After that, it ran 180 all day long. Made a huge difference.

Braden

 

I've been running my SBC (330 hp) without a thermostat. Stays right around 150-160 degrees all the time. However, took it out the other day when it was cooler and it didn't run as well so I'm going to put one in.

Can an engine run too cool?

 

You really need to get the fan much closer or get a shroud on the setup. THe fan should be not much more than an inch away for best draw, and rule of thumb is if running a shroud, you should have the fan nearly centered in/out of the shroud. I have 'adjusted' the fan to radiator spacing on a few cars and dropped the temp considerably (15-30 degrees).
I run my buick(401) with just a restricted opening using the outer portion of the t-stat ring and it runs a little cooler than I would like. On the 327 in the wifes 54 Chevy, I run a 160 t-stat and it runs nice and cool. I would recommend using a t stat to get the engine up to temp and keep it there in cool weather as opposed to not running one.
You might find that if you get the fan in the right spot, there is no need to change or remove the t-stat.

 

jpmachado ...to answer your question..yes..an engine can run too cold and it isnt a good thing always..for many reasons..oil is manufacured to run a certain temperatures and it could coke up and leave a nasty sludge in your engine..and fuel consumption is increased..the operating temp of 180 to 200 is definetly a good area to run in..there are a few other reasons like engine wear and some others that play a role in too cool an engine..just cant put my finger on them tonight.

 

HR28

I've always had to use a thermostat. After going through about a half dozen, I came across the "Fail Safe" Brand. I use a pump riser in my hot rod and nothing works better.

Check it out for about $9.

RGV

 

I don't know why you wouldn't run one ,if heating is the problem you need to look at other things.No thermostat will keep it cool on short trip,but once motor gets warm it ain't gonna make a differance.

 

Im using a flathead 8ba. I have no thermostats. I found when i used them my motor ran hotter than normal. To help compensate i installed a electric fan plus it helps that im not using my hood. Since i have taken them out, my motor runs much cooler. On the freeway i can keep up with traffic and it will run around 180-190. And with all this it helps to have a 200r4 backed up to it with a tranny cooler. So far its great!

 

i can think of a lot of reasons to run a thermostat, but to not run one in a driver none.

 

I agree with Da Grouch, But you live up north, so just run a cool thermostat. Hell, you'll need it!

 

my buddy swears by it in his '53 235.

 

the fan being 5" away would be more of a problem when your going slow, at 30mph and just crusing your car should run as cool as its going to, the fan doesnt do much at speed.

 

On our 406 sbc alcohol burning dirt car with an aluminum radiator, fan shroud, and a big fan. There was no opening in the nose for clean air so we had problems with it either not warming up or running hot. Our solution was a thermostat with a 3/16 hole and a bleeder valve in the thermostat housing to get trapped air out when filling it

 

Those comments remind me of when my brother was racing stock cars on dirt tracks decades ago. He had me fabricate a variety of restrictor plates to test which worked best at keeping the engine at preferred temps. I made some with holes of varying diameter and several with a number of small holes in one restrictor. Too many years have passed for me to recall which worked best.

For folks that wish to save a few bucks, they're simple to make. I merely used the bottoms of coffee cans, similar containers, or sheet steel.

Just place a thermostat housing on a piece of flat sheet steel; trace around the perimeter of it and inside its bolt holes with a pen, pencil, or a scribing tool of some sort; mark or scribe whatever size hole or holes you wish to use in the center of the marked/scribed outline; drill out the restrictor hole(s) and the mounting holes; cut the sheet steel on the marked/scribed perimeter; deburr the whole thing; and then, install it in place of a thermostat using a gasket or goop and test it out. Simple and cheap.

After fabricating your own you could purchase a store-bought one with a restrictor hole of similar size as your test piece, or, keep running your fabbed one.