I have done dyno tuning, but not for various collant temp stats. I agree that blanket statements are a bad idea, and yes - most of my EFI tuning experience was on 5.0 and 4.6L Mustangs, which typically won't get into closed loop until 170'F. Open loop = ignore O2s [and other sensors] and usually this means rich running. I couldn't tell you exactly what minimum collant temp an LS1 engine uses for starting closed loop operations.

But factory built engines are almost universally built with clearances set for 190-192'F running temps, because this is what most of them come with. Miniscule power advantages from running 30'F coller temps [or more agressive timing] aside, the various machined clearances [piston/bore, bearings, etc] are still set for a specific temp, right?

Iron and especially Aluminum both have substantial thermal expansion properties, yes? Changing their temperature changes their size, ever so slightly. When you are talking about .004" piston to bore clearances or .0025-.0030" bearing clearances...?

I would rather run the proper temp stat for engine clearances and pull a tick of timing to avoid detonation rather than try to eek out 1-2 extra hp by running the engine at 160'F or whatever.

To each his own. If there is some magical 20 hp to be unleashed from running cooler stats on certain engines then I guess I am the sucker and you'll have that advantage on race day and/or for your customers. On a drag car motor, with much shorter life spans, maybe there is more reason to do this than I can fathom.

Damnit - I said I wouldn't argue this one again... I'm stopping here, I promise. Die dead horse, die! Or we will beat you some more!

 

Yes this horse is big, super human power and near immortal.

The GM cars arent like the ford's. If the GM car doesnt reach said temps by x amount of time but has reached a lower temp it goes into closed loop anyway.

The ls1 likes to be ran cool, just doesnt lose huge amounts of power hot.

My car would run 178-188 with a 160 thermo and fans on sooner in the summer. Thats where my car ran best with no knock, on the dyno and the track.

 

Thanks for the links and pics

 

My'n went out at 29K miles..it now has 40K....But i have always been suspicious about it. The Chevy stealership is litterally about 1 mile away from my house..i drop off the car for a front end allignment, i get a call about an hour later saying that i need a new water pump b/c my'n is blown..i go down there and there is a huge puddle of coolant under the car. I drove the car all day the day before i brought it there, and some how the water pump blew with that 1 mile trip to the dealership...oh well..they can go out at anytime..atleast it did it on its way to the dealership..and not in the middle of no where.

P.S.-My warranty did not cover it..The warranty ran out a month before this incident.

 

160 stats


whoever said 1-2 hp gain with a 160 stat doesnt know performance. Chevys love colder temps and run a hell-ova lot better with a 160. My LS1 stays at 170 and the response and power is VERY noticeble as to when the engine temp is 220 = stock hot temps. personally I feel better knowing the engine bay is more cooler and feel the engine and components will stay together for a longer time.

99 Z28
84,000 miles

same water pump, same everything, never a coolant leak or oil leak. runs like its brand new.