BlackDemonSS

Ok pure the instruction of the guy that tuned my car today he recommended i put a 160 thermostat in my car for best results. he has been tuning since the LT1 and is a highly respected guy. i do all the maintenance on my car. On a nother thread a debate has begone between AWDTBSS and WhiteKnight'01 on whether i should or shouldnt put the thermostat in my car...Keep in mind i live in california and Southern california at that so let me know your opinions everyone

sjsingle1

iTrader: (1)

i say 160.......other opinions may vary

Canbarelygo

i definately say 160

LS1121

iTrader: (17)

I have a standard 185 and have no issues. I live in southern NC and it is very hot here also. I can't see what a 25 degree difference is going to make. GM designed the motor to run at a specific temp. But......we all know most people are smarter than the Tech's who designed the car. lol lol Just a personal choice I guess, unless someone can offer why the metal would perform better at a lower temp.

Canbarelygo

its just personal preference i suppose. i just like the idea of lower temps for more reason than 1. it helps reduce the chance of alot of bs and the dreaded #7 piston meltdown. also the cooler temps i would think would cut detonation down but thats me spit balling.

i know for a fact as i witnessed it in my driveway we put a real time scanner on a buddies stock t/a with the stock thermostat and it got up to 227 before goin back down. thats a little high for my liking

WhiteKnight '01

I'm watching this thread closely, would like to see more opinions on here. I for one, am against it. I think the car was made to run at 200*, running it cooler will give you no HP gains or any other advantage whatsoever.

I remember having this same argument on another forum when I owned a 3.8 V6, granted those engines are a bit different than the LS1, I think the same rule of thumb applies here though.

Also would like to point out, from what I have read, (I don't claim to be an expert on these things) that the viscosity of the oil will thicken if it is not kept at a high enough temperature, right around 200* for conventional oil, maybe a little bit less for synthetic. Anyways, the less viscosity of the oil, I think that fuel economy would suffer slightly, you'd have more sludge build up in your engine, and you might be robbed a couple of HP. Someone correct me if I'm wrong.

ULTIMATEORANGESS

iTrader: (4)

im running a 160 but im highly modded.



ive never heard of them being harmful.

WhiteKnight '01

I forgot to include that part. A 160* stat (from what I know, again I don't claim to be an expert) will be beneficial on a well modified car, I.E. cam/heads/headers, lots of bolt ons, S/C, T/C, etc. But on a mostly stock car it will do nothing.

Also, if you live anywhere where it gets cold in the winter, which is basically anywhere outside of the very deep south, a 160*stat will make your car take a lot longer to heat up. So if you like a cold car ride in your DD, then by all means, take it.

LS1121

iTrader: (17)

So are you saying when i do my 799 Heads, LS6 Intake and Z06 Cam swap on my 98 LS1 I need to go with a 160 thermostat?

BlackDemonSS

this was from a guy on ls1.com "HP??? maybe,,,,,but what a cooler stat does do is help the engine to be more octane tolerant,,,,which in turn allows you to be a little more aggressive with the tune. In that respect you may see a few HP. It's a fact that the cooler the engine runs the less prone to detonation it is. With that said you can usually squeeze a little more timing in,,,there is a point where the engine will stop making power with more timing,,,but you may never get close to that point with an engine operating at 220 degrees.

I believe the main reason all engines come from the factory with hot thermostats is for emissions reasons,,,to burn off more hydrocarbons.
That could be an entire book of discussions.

Another reason I like them is for the simple fact that,,,if the engine is running cooler,,,that means cooler under hood temps as well,,,,which is much easier on all the rubber and plastic parts under the hood, belts, hoses, clips, plastic tubing etc....which these cars are stuffed full with. Also with cooler under hood temps I can't help but think that helps to keep the air intake tract cooler as well,,,,,which sits right on top of the radiator,,,and we all know that cool air is dense air,,,and makes more power as well.

This may all sound nit picky to some,,,but it's why I run a cool stat in all my cars."

http://www.ls1.com/forums/showthread...ermostat/page2

BlackDemonSS

i can see the logic in having the motor run hotter to burn-off more emission

WhiteKnight '01

Alright, I'm willing to admit, you make good points on the timing/tuning and all that. And cooler under the hood temperatures might help you a tid bit. I think you can argue either way with a cooler stat, but at the end of the day on a mostly stock car, it's not going to do anything for you, $20 for one of these, save that money and go buy some pizza and beer, more worthwhile.

jimmyblue

iTrader: (11)

Pay attention now... thermostat on these cars DOES NOT set max coolant
temp which is what "performance" arguments are based on. It sets the
minimum running engine temp, which affects stuff like how well you cook
the blowby volatiles out of the oil, vaporize fuel, etc.

If you want control of your motor you have to fix everything BUT the
thermostat. In the southland with a dirty stock radiator and running
A/C, you will fail to hold setpoint on a 160 'stat. I saw nothing from
the swap and went back to stock 'stat when I upgraded the radiator.

If you tune for 177F ECT and you fail to maintain 177F, that's ping on
you. If you tune for the worst case temp then you are leaving some
on the table at 177F.

Spend your money on a better radiator, your labor on cleaning out
the rad & condenser, and get the fans set right. Then you do not
need a "160" 'stat unless you are way modded (CR / boost) - and
have the cooling system to make use of it when it counts, not just
at idle & cruise.

BlackDemonSS

well heres a link from a GM design engineer for the cooling system on the ls1...
http://forums.corvetteforum.com/1557142528-post8.html

senicalj4579

iTrader: (41)

Im a fan of the stock t stat. I have different fan settings and thats it. in the summer coolant temps "most of the time" stay 194-203. Perfect for an ls1.

senicalj4579

iTrader: (41)

I had a talk with that guy a couple years back. He knows his stuff. One of the reasons I keep my stock t stat with lower fan settings.

BlackDemonSS

another link by the same guy...
http://forums.corvetteforum.com/1554901004-post64.html

Well as it sits right now the first fan comes on at 193 and the second at 200... Im still gonna change my plugs like i should. Do you guys think i should just leave the stocker in or maybe get a thermostat in between the 160 and the stock thermo?

senicalj4579

iTrader: (41)

Your low speed comes on at 193 with the stock t stat? They must be running alot.
Mine are set low on at 203 off at 196 high on at 208 off at 204.
Most guys will say go with a 160 t stat but I believe a stock t stat is the way it needs to stay. Send a pm to evil twin hes got some good info.

WhiteKnight '01

I like this above write up. He goes into it in a lot more detail than I ever though of, sounds like he knows his stuff.

I'm glad this thread was started, we got a good number of opinions on here. Gotta say though, seems like a 160* stat will not get you anything like I originally said in the other thread.

WhiteKnight '01

Just read that write up, thought I would post it on here for all to read:

I can tell you from first hand design knowledge that anything below 170 F for long periods of time will destroy an ls1. The shear alone will destroy the lubricity of the oil. It's not a question of if it will harm, but when it will harm.. running at these temps for long periods of time will cause catastrophic damage. I have seen it on our test platforms.
The sweet spot for an Ls1/6 is 180/200. All part of the design with very tight clearances, to help extract the most performance. On a stock lower end, too cold will rob the motor of HP, the motor has to work harder when cold. Thats why we put cold starts into the algorithm for the oil life monitor, because it destroys the oil.
Good Luck
Bill aka ET

What he says in there ties in with what I said about the oil getting too cold and losing its viscosity. Remember I also mentioned there were some negatives about running that cool of a stat? More oil sludge build up, decreased fuel economy, rob you of a couple of HP? Now this guy says it will cause damage on the long haul, I'd heed his advice. So much for your tuner who recommended this to you, sounds like he just wants to make another quick buck off of you.

Sounds like this "random guy on the internet" might know what he's talking about.