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Need more heat - which thermostat

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Robby

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My 79 MGB runs good and cool all through the summer - and winter. Now that it is getting a little coller out - and I still want to drive my B some - I need better heat. It blows great and warms pretty well but since the car runs so cool, the heat isn't as good as I woudl like. I figure changing the thermostat would make a huge difference. I am pretty sure it has a 160 in it now, should I just bump it up to a 180 or go all the way to a 195?

Thanks

Robby
 
Just block off the rad some.
 
My Volvo 122s came stock with a window shade arrangement to block off the radiator. Of course I never needed it because I've never been anywhere below 15 degrees F. :smile: Ever.
 
What's a good way to block off the radiator? I have a similar problem in the spring and fall with my B -- car never even gets to N on the temp gauge.
 
One of my pals used to use a piece of cardboard. But I know nothing about it other than hearsay.
 
drooartz said:
What's a good way to block off the radiator? I have a similar problem in the spring and fall with my B -- car never even gets to N on the temp gauge.
Click to expand...

I'd go for cardboard that's what most cars i see use
 
I run an 180 thermostat in the MGB year around and have no problems. The needle runs dead in the middle of the normal range. The rad has a new core and the block was cooked before rebuilding. If the thermostat in your car is an older one, it's possible it's not closing fully. I'd put a new one in. But that's just me. PJ
 
All you need is a piece of cardboard and 2 small pieces of masking tape to hold it in place when the car isn't running.

Start with the lower 1/3 and then work your way up.

Or use a 195 tstat and then see if you have to add cardboard to cut the flow down.
 
When I was in college I would use a converted pizza box on my Sprite. Worked fine, didn't put it on until real winter started around christmas, then blocked off a good portion of the rad maybe 50% or more by cutting a squre hole in the box which was trimmed to radiator size. I don't recall ever using anything to hold it in, I think I just trimmed it to a size where it could tuck under various lips on the radiator or other handy parts in that area.
 
If, after trying the cardboard and the new stat, you still don't get enough heat, google or search for the modified heater valve trick. Takes about half an hour, but it greatly increases the flow through the core.
 
Another way is to increase the fan speed. I have some help on that buried in my computer 's attic somewhere.
If interested I'll up and see.
 
I am curious as to why GM, Ford, Chrysler and every other car manufacture in the world, didn't use the cardboard method than a sophisticated temperature controlled thermostat designed for a particular engine? I guess those $100,000 + a year engineers need to go back to school and learn the cardboard method, as it would be much cheaper in the manufacturing process. I guess their not as smart as I thought they were. But that's just me. :blush: PJ
 
It all depends on where you live. My stint in north dakota cardboard was needed on pretty much anything modern that you wanted heat out of in a reasonable time in the middle of winter. Nothing was worse than getting to the cusp of having the slightest bit of warming coming out of the vents then getting stuck at a stop light and with it the return of icy air out of the vents. On the coldest days in a car that was fully warmed up you could loose heat when stuck at a stop light.

Once of the bigger reasons I bought my current car was the fact it had an electric aux heater that puts out heat pretty much instantly.
 
Good point on fan speed/volume, most of the LBC's I have owned have not problem producing warm air but there is just not enough flow to heat even the small interior of an LBC, or in this case MGB. I think there are some tutorials on the internet about getting more juice to the blower motor, I remember reading one article that the wire guage to the motor should be increased to get proper voltage, but have also read that is not necessarily correct.

Greg
 
According to Vizard, 180 F is the best compromise between power and efficiency. So use a 180 or 185 thermostat and supplement with cardboard as needed.

--Jack
 
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