i have an 84 TA with a stock L69. i have a 195 thermostat and want to put a 160 in. the guys at the local auto parts store told me not to put one in so they gave me a 180. so is a 160 too low for the computer? and i live in PA so it does see cold weather.

 

also, should i switch back to a 195 or 180 in the winter when it goes below 32 F

 

160 isn't too low for the car to run right. All the computer does in your car is control timing adv/retard. It isn't gonna blow much heat but it will run better and alot cooler.

 

if you live in a cold climate i'd stick with a 180. i'm using a 160 but i'm down here in FL. weather's too hot in the summer to keep the engine temp anywhere close to 160.

 

I just ordered the 160 thermostat and fan switch today. I figure I'de test it out to see how I like it since it's not too expensive anyways and if I want I can always just go with the 180 in the future. I have a 160 with fans for that temp and it blows hot air in the cold just fine and I liked it so I thought Ide try it on my 92.

 

180 is usually the best compromise if you think 195 is too hot, if you have a 160 and the cooling system is good enough to make it run 160 all the time the piston rings and the bore will wear out a lot sooner.

 

care to elaborate on that?

 

i'm really wondering what u mean by that, y would they wear out sooner if the engine is running cooler

 

I don't know about wearing faster. I don't believe it's true, but stranger things are.

I do know that Smokey Yunick found 170* is an optimum compromise between power (efficiency) and wear.

IMHO, it's better to be a little warm than a little cold mainly due to combustion efficiency. Combustion chambers like heat (not to be confuse with "hot spots"). The warmer the combustion process is, the more efficient the burn. Cooling off the engine too much compromises that.

And the guys at the parts place are right. Unless you have the computer reprogrammed, you will have problems. The PROM is designed to run at 14.7:1 A/F ratio ~200*F. If you alter that, the ECM isn't going to like it. It will idle weird, you'll get worse MPG, and you're not going to gain a lot of power if any.

Reprogram the computer (new chip) and you won't have those problems.

 

160* stat won't damage an engine.
if you do search seems most with computers find 180* work bettr, but just be sure to get a lower rated fan switch.

 

Does the computer really control the air fuel in a carb car? Not to mention reprogramming is nearly impossible for a CCC ecm. The secondaries are completely out of the computers control so the cooler engine will defentally run better at WOT.

 

def not too cool but some will say the best gass milage is at around 180.... too cool would be around 125 ish but thats near impossable

 

I'll try to find the article about the cooler temps increasing bore wear, it was years ago that I saw it, it was an auto manufacturer test and they ran engines at different temps to find what resulted in the longest life, and I think it was around 190-210 deg. was the best, 180 had a little shorter life but anything cooler than 170 really had a lot shorter life.

 

Hear is one thing I just found after a quick search, not what I was looking for but it has about the same results. Read and look at the chart at the bottom of the page, it says best temp is 175-180 deg. and the bore wear is double at 160 deg.

Bore wear vs. engine temp

 

A buddy of mine has a 24' boat with a 350 SBC in it, it's salt water cooled, so to keep the corrosion down it runs at 140 deg. He installed a brand new engine 3 years ago and has run it 350 hr. in the last 3 years, it started using some oil and then it dropped a valve, destroying the engine, so we pulled it apart and the cylinders were really wore out, they had .010 wear at the top of the bore which I think is because of the cold temps. He's putting in a new engine with a better valvetrain now, but he's adding a heat exchanger so it can be cooled with regular coolant and going to run it at 180 deg., we'll see how long this one lasts.

 

Is that why I am only getting 16mpg with my 305TPI?
My engine runs at 155* most of the time with stock programming.

 

i dunno, mine runs right at 160 and thats with the 195 thermostat. I dont think the stock guages are that accurate.

 

Wow...Mark A Shields knows more about engines than Smokey Yunick and David Vizard!!

They're both published saying 170degF is optimum temp, and that the lower temps afforded by a 160deg stat will wear an engine faster than the correct temp.

But hey, Mark A Shields must have quite a bit of data to support his assertion and prove them both wrong...