rsylxstr , hows it going ?
If we may , lets sorta start this again . ( Keep in mind I've messed up my bold/graemlins - java script thing so CAPS are FOR EMPHASIS ONLY )
Quote:
how bad of an idea is it to run the 180 degree thermostat in my 2001 F150 5.4L?
1 (( Short answer ; DEPENDS . ))
1a (( Somewhat longer answer ; somewhere between very bad - to ( OK - marginal tradeoff net benefit//not worth - worth doing ) - to good/ great idea ))
on another forum, i'm hearing it will make it wear faster (( AND/OR COST MORE TO OPERATE )) and i should change the oil every 1k miles.
(( Again , that would Depend on a lot of things not covered ))
BTW, i'm running a K&N Series 77, cat back exhaust and Hypertech Power Programmer
MC5W20 said the following in various posts here, and his comments are a very good foundation to work up from .
( my mods in (( )) . Also some unaccounted for editing .
A ) I disagree with this 100% ((60 - 90%)). I will even go farther and say about the above - you (( are taking the/a special case(s) for the general case )) (( and have over generalized somewhat in regards to )) what your talking about.
B ) Under no (( limited - to very limited )) circumstances should you change your thermostat (( 15 degrees )) ON YOUR 2001 Ford F150 with the information we have so far , with the mods listed , and operated in upstate/central NY State .
This is subject to change with more information .
C ) Your computer (( and your engine/engine subsystems in general are optimized under certain assumptions so it )) is calibrated for this (( thermostat function/ )) temperature.
D ) (( One of )) The most mis-understood aspect of modern gas engines and the computers that control them is the importance of the hi-temp OEM thermostat.
(( Yep , although I wouldn't call a 195 hi temp - also need Cap pressure . ))
E ) (( It is more common/quite possible )) I assure you , if you change it (( -15 )) you will (( may/likely / need to investigate farther to prevent/determine )) lose way more then 1/10 of a MPG (( and maybe more importantly , depending , could create other undesirable outcomes/tradeoffs as well. Then again in regards to fuel economy , maybe not AND with a HYPERTECH IT (MAY) DEPEND(S) ON HOW YOU DRIVE/USE IT -it might even be " higher " ))
F ) All around (( For 80 -90% of the people/ 80 - 100% of the time its just a bad (( inefficient or good to poor second/third choice )) idea to change to a lower (( 15 degree )) temp stat.
I once was of the opinion lower temperature was better. It took me a lot of research and reading technical papers to change that way of thinking .
G ) Your fooling yourself if you think a hotter thermostat is ONLY used for better fuel economy.(( Yep ))
H ) I never said engines didn't wear ACCEPTABly at lower thermostat temps. Just making the point that they (( more often/usually when considered as a power plant/cost SYSTEM )) wear better at the (( factory optimised )) higher temp.
I ) Thermostat changes (( AND MALFUNCTIONS FROM SLUGGISH to small to large )) are why people have a lot of "unexplained" problems on computer contolled cars/trucks
(( Big time YEP . ))
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So then , there are the special cases ie 20 - 10% of the people/20 - 1% of the time where its a OK/good/great move .
( Good move arbitrary definition - acceptable trade off for useable gain - ALWAYS IN THE EYE OF THE BEHOLDER. )
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Gary Allen covers the most important situation/concept ( GENERAL/SPECIFIC DEPENDING ) where gain could/does occur here .
" There's no gain to running a 180F thermostat in one spec'd for 195F unless it's in a Hi-per " ((AND/OR HIGH LOAD/HIGH HEAT - GENERALLY RPM INDEPENDENT )) setup (( situation )) where your WOT ( not necc . although agreed more common/important ) -
- (( RPM/THROTTLE SETTING/ ( air/fuel mix. )/ LOAD MATRIX ie " engine HEAT GENERATION/COMBUSTION CHAMBER PRESSURE )) event " overwhelms " your cooling system
(( OR WHEN THRU CYLINDER HEAD TEMP/PRESSURE VALUES - FUEL DISTRIBUTION PERFORMANCE ETC YOUR OPTIMAL SPARK ADVANCE SCHEDULE IS NO LONGER AVAILABLE/SELECTED OR WORSE , " YOUR SYSTEM " CAN'T RETARD ENOUGH TO PREVENT PREIGNITION/DETONATION WITH THE OCTANE/FUEL/ " CONTROLLER MOD " YOU ARE RUNNING AT THAT MOMENT .
Variation on a theme ;
(( AND/ OR really warms up your clyinderhead/piston assembly/combustion chamber surfaces/deposits )).
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It will give you whatever time that it takes to reach 195 ..that's it. "
(( which may be useful if you're really cutting it close OR LOOKING FOR A BURST MODE KIND OF " BOOST " but more typically is too short to give much practical benefit .
(( More specifically to your situation/application this type of logic also applies to when a more agressive Spark advance schedule is applied/or could be applied for gain as well - so again , theres the general case the special case and YOUR case and it depends .))
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I posted earlier and I'm going to flesh out the following ;
Personally , I wouldn't want a 180 in upstate NY in the winter .
( Unless I was plowing/towing and seeing substantially elevated coolant temps on a fully functional/maintained strong running engine .
(( As far as trans goes I WOULD HAVE ALREADY SUBSTANTIALLY upgraded many things - or I wouldn't be using this truck for these purposes ))
I would recognise this as a somewhat 1/2 a**ed but acceptable 1 season solution until I could properly upgrade my cooling system .
" Given your other mods/and street use ( intake/exhaust mods which hopefully , in situations where it would be helpful , already are giving you a small but useable net decrease in " knock/ detonation tendency "
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These are some of the cases that G A/myself are talking about - including the ones where you really don't want to have to stop .
" - on a maintained engine thats not towing large and heavy up a big hill ( fast or slow )..............................I'm not sure what you would really accomplish and if it would be worth it "
Of course, a 180 degree thermostat won't really HURT anything in the vast majority of cases- it simply isn't worth the trouble (usually). But if this guy is running an aftermarket chip that reccomends said thermostat- then ByGawd he ought to run it to get the maximum effect of his monkeying around with the well-engineered stock setup. That engine can still run many hundreds of thousands of miles at 180 degrees and there will be absolutely no measurable difference in wear.
