INMY01TA

iTrader: (1)

160 here.

Paul57

I have seen a chart on longevity (wear) verses power with different thermostat settings. It showed that 170 degrees had the best combination of engine longevity and power.

However, (my opinion) that a warmer 180+ may provide better MPGs (and emissions) allowing more vaporization...at the expense of HP because of the warmer (less dense) air and thus (likely) allowing less timing (less power in most applications). MPGs and emissions are far more important to GM than a few HP.

It seems that most of the 160 stats don't get below 170 temps...from the posts here. How much HP is this worth?...would be a great test and would interest everyone. Right now it seems that it is mostly speculation. If you run synthetic oil, then the longevity question/issue is almost a non-factor.

FiredUpZ28

Wow this thread went from hearsay to fact real quick. Definitely interesting hearing everyones views on the subject.

WeathermanShawn

iTrader: (1)

I still respectfully think there are few documented facts when it comes to testing of an ideal LS1 ECT for maximum power and engine longevity.

A lot of the online material does not seem to pertain to LS1's. For whatever it is worth, just observing a 2002 LS1 ECT/IAT Spark and Fuel tables. ECT plays a far greater role in engine VE at idle and low speeds. IAT is far more critical for engine performance. On a 2002, timing is not pulled until you hit an ECT of over 212F. Hot IAT's pull spark and HP exponentially faster than ECT's at highway or WOT speeds.

I guess when people say 'I have not had a problem with a 160F Thermostat', I do not know if that is purely subjective, or they dynoed and gained 10Hp running a cooler engine.

You can read forever, but at least from a tuning perspective it appears that if you can reach at least 176F on your ECT..nothing changes tuning-wise until you hit over ~212F.

That is not the definitive word, but in all honesty I think only someone posting a dyno sheet with various ECT's would ever solve this debate.

Respectfully.

..WeathermanShawn..

disc0monkey

iTrader: (10)

lets try to gather results of actual sustained temperature. I would like to get some more insight.

give your state and season that you recorded your temperature, also major mods.

Gregorya24

iTrader: (13)

stock thermostate i like running my car around 190 heat is power

Paul57

Part of the advantage with a cooler stat (160) is the ability to run more timing without spark knock. It would not be a surprise to find out that going from a 180+ to 160 netted minimal power without a new tune.

WeathermanShawn

iTrader: (1)

See Paul, I would like to see 'proof' of that (on a LS1).

I understand that if the air entering the intake is cooler and more dense then that makes sense. If the IAT is cooler, it is easier to run more timing (usually).

I have seen a couple of polls on LS1 Tech..if memory serves me right, a majority ran 180F Thermostats. I have seen a couple of threads where one OP made his maximum engine power at 200F.

I guess this is one where I would like to see some dyno numbers as various engine temps (LS1's). My conjecture is that it is of such minimal power gain/loss that few spend the money just to test it.

And please do not take my views personally. If you prefer one engine temperature over another that is your prerogative.

For the record I ran a Thermostat that is fully opened at about 190-195F. I set my fans about 20 degrees (F) higher. In my humble opinion IAT controls fueling and spark to a much greater degree than ECT. Perhaps if you are sitting at a track waiting for your next run, you might have to take a different approach.

If anybody has any objective data, I am always wanting to learn more.

Thanks.

..WeathermanShawn..

Ice78Transam

iTrader: (1)

Higher engine temperatures are conducive to lowering emissions. Thats a large reason for the higher temp from the factory. But really, I'd do a coolant flush first. Increase the systems capacity to cool, not its workload. And it has been shown time and again that LS engines perform best with a little heat in them.

LS6427

iTrader: (2)

My stock LS1 always hovered around 210-220*, pretty much no matter how I drove the car in HOT weather with my A/C "on" or "off".

When my 427ci went in, along with a 160* t-stat and tuning the fans accordingly to come on a little earlier...almost 8 years now and my 427ci engine, on a 90* day, in traffic with my A/C "on"....never see's more than 200*. It will only get hotter than that if I stomp all over it in those conditions.

On the highway cruising steady with the above same conditions...it runs about 185* constantly. If I run around a race it around with the A/C off it really never gets above 185*-190*.

The 160* t-stat will do two things.

-You will perform a tiny bit better simply because a cooler engine performs better.

-You will get longer life on just about single part of the engine, the hoses, the wiring, alternator, A/C compressor, sensors...etc, etc, etc.....

A cooler engine and engine bay = longer lasting everything.

.

Paul57

How much is "a little heat"?

Paul57

I would like to know if he had an "additional" way (cool can - ram air - etc.) to keep the fuel and air from getting heat soaked.

I believe the combustion chamber should kept hot for maximum vaporization...but, everything up to that point should be cool for maximum density. It is a compromise.