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I just installed a 160 t-stat with an intense pcm upgrade with it. I was telling some of the guys at work & they r concerned that I'm going to cause damage to my engine from it running too rich. They thinly running that cold the pcm will call for fuel constantly to heat it up. What is the real answer?
 

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I am not positive but I would agree. Also your oil is not happy that cold unless yuo have a nasty race set up or are running alot of non intercooled boost down south in the summer. My uncle dyno tests motors for ford and does alot the fuel mapping and they experament with different thermos all the time. He swears by a 195 thermo. Also when motors run to cold they tend to develop more sludge than normal. I would put a 180 in to be honest, your pcm wont need any retune though so you should be good. I wouldnt be concered abuot damage to the motor from running rich though. I think it is kindof the opposite.
 

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I run a 160*F and am thinking about going back t o180*F thermostat. My fans are setup @ 160 & 165*F and I found a lot of sludge on the inside of the valve covers, the forged pistons don't like it either, they have a lot of slap when cold, kinda like the 3100 V6 in my beater. I have ran the engine @ 180*F and seemed to run smoother. Doesn't hurt to have both thermostats, at least they are a cheap mod ;)
 

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I disagree completely. At my shop in the winter we see several different types of cars that come in with a check engine light on and a cold coolant temp failure code. When looking at the data stream from these cars PCM's, we have never see any excessive fuel trim changes caused from cold cooling systems. If you were to run it with a coolant temp well under 100 degrees, maybe there would be some correction. I personally run no thermostat in the summer and a 180 drilled in the winter(this way if it does get out of the garage in winter I will have a little heat).

Next time someone tells you that ask them to show you some recorded data supporting their claim.

Good luck, Jake L.
 

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160* is pretty unnecessary, you're not gaining anything from it, just shooting your mileage down some more. Depending on where your fan triggers are you may want them readjusted for running a 180
 

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your fine where you are with the 160. I'm running a drilled 160 in my gt with timing up'd out the azzz.. And my mpg's are high 20's-30's in the city and mid 30's on the open road
 

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It's up to you, personally i'd just run a 180 on the street and if you want to just pull it out completely for the strip, but it does get a lot colder here than Missouri, maybe you won't see the same kind of drive-ability chagnes
 

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I'll keep my 160, thank you!! It's still warm down here!!!
 

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My engine only has approx 8000 miles on it since major rebuild/mods. The inside looks as clean as the day it was assembled. I do however still have my PCV valve functional. If you block these off, you will see sludge build faster than normal. The rest for me is in frequent oil changes. I change it at or close to 1500 mile intervals. TWO reasons I do this are.... you will never seen an engine have a failure from dirty or contanimated oil, AND, if a failure does start, I will see it in the drained oil as it is examined as well as the oil drained from the filter. I slowly pour the old oil onto a flat drain trough and examine the oil with a light shining on it as it slowly runs past looking for any metalic particals. There were a few sparse flakes at first during berak-in but now it's as clean as when the oil came out of the bottles(motocraft super duty diesel oil 10w30). Heck, now that it's settled down from break in, maybe I could go all the way to 2000 miles between changes.

Good clean oil is the easiest way to ensure good engine lubrication and lessen the possibility of a failure....my 2 cents

Jake
 

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Oh there is one more thought I have concerning oil sludging and thermostats. I believe running a hot thermostat or running the engine consistantly hot will eventually cause a small "baked on" oil film on many internal parts. This usually is somewhat normal and minor in most cases without harm unless you try doing a crankcase clean and flush. If you do this, there is a very good chance the sludge could be caught in the oil pump pick-up screen or oil filter and cause a major bearing/lubrication failure.This happens cause crankcase cleaner works very well. But a large amount of this sludge in the oiling system causes havock. If you insist on trying to clean the crankcase, do it with 3 or 4 rapid succession oil changes (say 500 miles apart). New oil will have very good cleaning ability. This may seem like a wierd way to demonstrate, but next time you hands are full of grease/grime, pour some clean oil in your hands and use like a hand cleaner. You will be surprised how well it works. Don't ask how I found this out...........

Jake
 

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ATF has a lot more detergent than motor oil ;) use a quart in your next cycle and you will see some dirt coming out of the engine when you change the oil.
 

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At 160*, it's unlikely the oil pooling temps are high enough to properly evaporate moisture in the oiling system. For our supercharged cars, a 180* stat should keep the pooling temps at 212* or a little higher.
 

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What I am saynig is that oil is not designed to run that cold is does not flow right and is not at the right vicosity therfore could cause a major bearing failure or outher pajor failure. Why do you think that you never go wide open on a stone cold motor? And why is there a thermo in a car to bgine with? Because heat makes power. Too much heat doesnt, but you need heat to make power. And believe it or not if your car were to over heat you would have a had time getiing it cooled down because when the coolant becomes super heated it does not spend enough time in the radiator because there is no thermo slowing the coolant down. And thats why ever car has a thermostat from the factory so they run correctly and have maximum reliability..... :icon_conf
 

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I hope this isn't one of these discussions that never ends, but then again, everyone here has their views and so be it. The talk of running a colder thermostat or maybe none at all during hoter weather(like me) goes further than many here recoginize.

First issue is the reason one would want to run a colder cooling system is to keep the upper engine cooler....heads, intake, combustion chambers, etc. This where fuel delivery occurs and this is what one would want to keep cooler. This said, how much do you think running a cooling system at 160 to 170 degrees is going to cool down 1400 to 1500 degree combustion temps that saturate the entire bottom end of an engine? And, don't you agree that these kind of temps will more than keep the oil plenty hot enough to do a good job? If there are any doubters out there, run you engine at 160/170 and drain the oil. Oh, and while your at it, pit your hand in that draining oil and tell me it's not warm enough to fo the job. Or better yet, use a pyrometer on it to check actual temps. It will probably be 250 or more. The only oil temps the cooling system has direct affect on would be the trans fluid via the coolers in he radiator tanks.

Guess I better shut up now and onto another topic. Thanks for listening, Jake
 

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I have been running the 160*F to try and keep the supercharger cooler and also to help out the intercooler any way I can- phenolic spacers, very low contact area with the LIM, freon cooling etc. The engine does run a little rough at these temps (160-165*F) and oil pressure is low due to my huge oil cooler infront of a constantly running cooling fan. I am soon going to 10W30 (from 20W50) and will raise the fan triggers to 180 and 185*F. Hopefully the little hotter supercharger will not cause any extra KR so I don't have to lower the blower boost and turn up the turbo :icon_conf
 

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It will probably be 250 or more.
Oil pooling temps for cars like ours are about 30-40* higher than the coolant temps. Corvette guys see temps like that after running down the track at WOT. Ours should be similar.
 

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The point is not to cool down combustion tempature. Because again you just want the radiant heat to be lessened and also once again that is what makes power. You do realize a car can over heat very easily without a thermo right? Just be careful. And you will gain very very little power running no thermo. You might actually be loosing because your oil is not hot enough and is thicker and is causing more friction. Not worth the risk imo.
 
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