LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Ever had an LT1 that...

Thread Tools
 
Search this Thread
 
Old 09-10-2013, 09:06 AM
  #1  
TECH Enthusiast
Thread Starter
 
93Euphoria's Avatar
 
Join Date: Feb 2012
Location: Orlando
Posts: 631
Likes: 0
Received 0 Likes on 0 Posts
Default Ever had an LT1 that...

Stayed at around 165 degree’s? Ran my car yesterday from Orlando to Tampa and the needle got no more than a hair above the 160 mark. It was at that point of it making me nervous. “Is my gauge broken, is the car really running this cool, ect?” I thought it might of been my Tstat broken open. Then this morning I drove her and she didnt do that again. around 180-200. Is that too low of a temp? The hell happened? Very strange but as long is its reading accurately I wouldn't mind if it ran 165 the rest of its life.
Old 09-10-2013, 09:16 AM
  #2  
TECH Enthusiast
iTrader: (22)
 
Stroked96Bowtie's Avatar
 
Join Date: May 2007
Location: DFW, Tx
Posts: 739
Likes: 0
Received 0 Likes on 0 Posts

Default

Sounds your t-stat might be hanging open. Mine always ran between 180-200 no matter what the outside temp was.
Old 09-10-2013, 01:35 PM
  #3  
Teching In
 
beaver50's Avatar
 
Join Date: Mar 2013
Location: KENTUCKY
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
Default

Mine always runs around 160.the first engine I had in it ran around 150.
Old 09-10-2013, 03:24 PM
  #4  
TECH Fanatic
iTrader: (2)
 
draggin97s10's Avatar
 
Join Date: Mar 2009
Posts: 1,471
Likes: 0
Received 0 Likes on 0 Posts

Default

mine stays about right there on the gauge but the computer says it stays at 173 electric fans on switch and 160 tstat
Old 09-11-2013, 07:33 PM
  #5  
TECH Addict
iTrader: (7)
 
KW Baraka's Avatar
 
Join Date: Apr 2013
Location: S.A., TX
Posts: 2,180
Received 130 Likes on 99 Posts

Default

Orlando to Tampa?

On the expressway?

70+ mph the whole way?

That would EASILY explain the low temps.......

IMHO, of course .

KW
Old 09-11-2013, 08:14 PM
  #6  
8 Second Club
iTrader: (2)
 
fex77k's Avatar
 
Join Date: Sep 2006
Location: AR
Posts: 1,668
Likes: 0
Received 1 Like on 1 Post

Default

Mine used to run right around 165-170, mild weather here thou.
Old 09-11-2013, 08:35 PM
  #7  
TECH Enthusiast
Thread Starter
 
93Euphoria's Avatar
 
Join Date: Feb 2012
Location: Orlando
Posts: 631
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by KW Baraka
Orlando to Tampa?

On the expressway?

70+ mph the whole way?

That would EASILY explain the low temps.......

IMHO, of course .

KW
Not as obvious as it would seem. Yes highway cools the motor down but before it would stay around 180 instead of 165. Just seem unusually cooler. Not to mention a 85 degree day, at around 80-90 mph 3000rpms the whole way.
Old 09-12-2013, 04:37 PM
  #8  
TECH Regular
iTrader: (3)
 
nitroheadz28's Avatar
 
Join Date: Aug 2012
Location: San Diego, CA
Posts: 435
Received 1 Like on 1 Post

Default

I have a 160* T-stat and fans that come on at 180 I think. Gauge indicates about 175* normal temp, my laptop shows 195* somehow.. lol

I put a pcm in with a stock tune for one night, ran at 225*. Now THAT was making me nervous.
Old 09-14-2013, 01:19 PM
  #9  
Banned
 
cardo0's Avatar
 
Join Date: Jan 2013
Location: Las Vegas
Posts: 588
Likes: 0
Received 0 Likes on 0 Posts
Default

So u want us to diagnose why your car is running good and cool instead of 20* hotter? Only gauge check i know is remove your temp sensor and place in boiling water to see if it reads 212* with ign ON but not running of course.

hope this helps
cardo
Old 09-14-2013, 01:23 PM
  #10  
TECH Enthusiast
 
BIGCAT7274's Avatar
 
Join Date: Oct 2011
Location: Apopka FL
Posts: 556
Likes: 0
Received 0 Likes on 0 Posts
Default

if the t-stat is stuck open they will run cooler than normal. you could pull it and see if its stuck.
Old 09-14-2013, 01:30 PM
  #11  
TECH Enthusiast
Thread Starter
 
93Euphoria's Avatar
 
Join Date: Feb 2012
Location: Orlando
Posts: 631
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by cardo0
So u want us to diagnose why your car is running good and cool instead of 20* hotter? Only gauge check i know is remove your temp sensor and place in boiling water to see if it reads 212* with ign ON but not running of course.

hope this helps
cardo
No, its really not a big deal. I was just curious. As a matter of fact I like the fact that the car runs cooler. But always heard that if the car runs too cool it would do some kind of harm in the long run and running without a Tstat would confuse the computer. Personally I dont see how running cooler can do any harm. Regardless im pretty happy around 160-200.
Old 09-19-2013, 10:24 AM
  #12  
TECH Fanatic
iTrader: (8)
 
96TransAmboosted's Avatar
 
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes on 0 Posts
Default

I run a 160 stat and stock water pump in florida as well never goes above 160 ever even on nitrous boosted runs still stays there. Coukd have been a fluke or a sign something maybe starting to fail like sensor ect.
Old 09-19-2013, 01:06 PM
  #13  
TECH Addict
iTrader: (7)
 
KW Baraka's Avatar
 
Join Date: Apr 2013
Location: S.A., TX
Posts: 2,180
Received 130 Likes on 99 Posts

Default

Originally Posted by 93Euphoria
......Personally I dont see how running cooler can do any harm......
'People' say that low engine temps is an indicater of low oil (engine and tranny) temps.....and that low tranny temps is a bad thing. Kinda runs contrary to the conventional wisdom of installing tranny coolers if we race these cars or even just install a performance TC.

My Impala has had a 160* T-stat for the past 15 years, or so. It consistently runs at about 165* on the HWY and about 175* in town.....unless I'm in a traffic jam; then, it skyrockets to about 190* ......

Anyway......I've only replaced the tranny once in all these years......so I guess I'm a bit of a non-believer like you .....

KW
Old 09-22-2013, 12:42 PM
  #14  
Teching In
 
Jaybdaboat's Avatar
 
Join Date: Mar 2013
Location: Indianapolis, in
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Default

I have an 180* thermostat. It stays at 170 city and hwy. but I drove over 35 a lot too lol
Old 09-22-2013, 04:35 PM
  #15  
TECH Enthusiast
Thread Starter
 
93Euphoria's Avatar
 
Join Date: Feb 2012
Location: Orlando
Posts: 631
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Jaybdaboat
I have an 180* thermostat. It stays at 170 city and hwy. but I drove over 35 a lot too lol
Really? Interesting, I had the idea that the stat open & closes at whatever temp it was and when it got lower than its temp specs its closes at that temp then, opens again after its higher than its temp spec (which in your case is 180) unless yours is broke open? lol


But as far as your 2nd comment; over 35 what?
Old 09-22-2013, 05:06 PM
  #16  
TECH Enthusiast
Thread Starter
 
93Euphoria's Avatar
 
Join Date: Feb 2012
Location: Orlando
Posts: 631
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by KW Baraka
'People' say that low engine temps is an indicater of low oil (engine and tranny) temps.....and that low tranny temps is a bad thing. Kinda runs contrary to the conventional wisdom of installing tranny coolers if we race these cars or even just install a performance TC.

KW
Couldnt agree more, some wisdom believes that doing anything outside of GM’s purposes on specs will do harm to an engine. You’ll get the common “I think GM knows how to make cars last longer than anyone who thinkers with temp settings" I’ve noticed that there are advantages to tinkering with stock settings sometimes (especially lowering temp settings)

But all temps effect all the other fluid temps in some way shape or form. Lower coolant temps = lower oil & tranny temp = longer fluid life. The cooler the fluids the cooler the cooling components. Cant forget colder colder engine bay will have some effect on colder A/C aswell Basically I believe the cooler everything is the longer it will last, cooler heads, cooler combustions chambers = cooler compression. LT1’s are just cooler engines than regular small blocks or LS’s , but LT’s flow horrible compared to LS motors. I would think that is the difference besides our ignition systems. lol



Originally Posted by KW Baraka
My Impala has had a 160* T-stat for the past 15 years, or so. It consistently runs at about 165* on the HWY and about 175* in town.....unless I'm in a traffic jam; then, it skyrockets to about 190* ......

Anyway......I've only replaced the tranny once in all these years......so I guess I'm a bit of a non-believer like you .....


KW
Im curious what is it about the stat that is senses what temp to open at? Is it a certain spring thats on there?! Its kinda of a newb question but personally I rather ask a stupid question with detailed info, than to ask a base question in which I learn no more than what temp stat it is.
Old 09-23-2013, 11:45 AM
  #17  
TECH Addict
iTrader: (7)
 
KW Baraka's Avatar
 
Join Date: Apr 2013
Location: S.A., TX
Posts: 2,180
Received 130 Likes on 99 Posts

Default

Originally Posted by 93Euphoria
......Im curious what is it about the stat that is senses what temp to open at.......
Quite frankly......I ain't smart enough to give a coherent answer to that.

However......with each 160* stat install I've ever had.....I also had the tuner (usually PCMforLess) set the tune to include the 160* stat.

So.....maybe there's something in the tune that activates the fans sooner.....or maybe the 160* stat just allows more coolent flow than the 180* stat?

KW
Old 09-24-2013, 01:25 PM
  #18  
Teching In
 
kamesama980's Avatar
 
Join Date: Jan 2013
Location: Columbus, IN
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by 93Euphoria
Couldnt agree more, some wisdom believes that doing anything outside of GM’s purposes on specs will do harm to an engine. You’ll get the common “I think GM knows how to make cars last longer than anyone who thinkers with temp settings" I’ve noticed that there are advantages to tinkering with stock settings sometimes (especially lowering temp settings)

But all temps effect all the other fluid temps in some way shape or form. Lower coolant temps = lower oil & tranny temp = longer fluid life. The cooler the fluids the cooler the cooling components. Cant forget colder colder engine bay will have some effect on colder A/C aswell Basically I believe the cooler everything is the longer it will last, cooler heads, cooler combustions chambers = cooler compression. LT1’s are just cooler engines than regular small blocks or LS’s , but LT’s flow horrible compared to LS motors. I would think that is the difference besides our ignition systems. lol

Im curious what is it about the stat that is senses what temp to open at? Is it a certain spring thats on there?! Its kinda of a newb question but personally I rather ask a stupid question with detailed info, than to ask a base question in which I learn no more than what temp stat it is.
I agree, "some wisdom" doesn't realize that ALL manufactueres comprimise to make a car usable for 99% of people, get good emissions, good economy, good power, longevity/reliability (but not too much, people still need to buy NEW cars) safe in a crash, etc. If you're willing to run closer to the limit or sacrifice one of those (or maybe comprimise them a little) gains can certainly be had elsewhere.

While too-hot fluids are bad, they need some heat. Engine clearances are specified around oil having a certain viscocity. While there's a large margin for error in engine's meant for the general public, newer powerplants with variable cams and variable displacement are dependant on calibrated hydraulics. I've heard multiple cases where the wrong oil causes those systems to get flakey. same for auto trans fluid. Most fluids in an engine want to get over 200f also to evaporate out water from blowby and condensation too.

The thermostat has a wax bead in the big central cylinder. As it heats up, it eventually melts and expands (thermal expansion, phase change=volume change) The chemical properties, volume, expansion space, etc are calibrated so that this happens at a certain temperature (not unlike adding anti-freeze to water to change it's chemistry thus it's boiling point from 212f to a higher temp.)

At the same point, the rated thermostat temp is NOT where the engine wil necessarily run it. the LT1 comes with a 180 t-stat from the factory and runs about 200-210 in normal driving (in stock spec, average temps). Depending on a number of factors the operating temp might be at the t-stat rated temp or much higher (or I suppose lower too...I haven't observed it happen tho). My FB, I assume, has a 160 t-stat and sits dead steady at the 1/4 tick mark on the gauge (~180-185f) but hasn't had the PCM touched so the fans still kick in at 225/235. Both of my toyotas have 195 t-stats stock and aftermarket gauges in the t-stat housing outlet read 205-210.

Last edited by kamesama980; 09-24-2013 at 02:19 PM.
Old 09-24-2013, 04:18 PM
  #19  
TECH Regular
iTrader: (5)
 
fruitsalad's Avatar
 
Join Date: Dec 2012
Location: So Cal
Posts: 441
Likes: 0
Received 1 Like on 1 Post
Default

Mine would go down to right around 160* on the freeway, then it would heat way up to ~210+ in traffic or heavy stop and go city driving. This was probably a combination of t-stat stuck open + the leaky head gasket lol.



Quick Reply: Ever had an LT1 that...



All times are GMT -5. The time now is 09:39 AM.