I know this topic has been :beatdeadhorse: ...revived and :beatdeadhorse: again but I can't sleep so let's get our sticks...shall we?

A couple of weeks ago I finally killed my "hunting idle demon" by pulling the intake and replacing every gasket and o-ring (to include the $18.00 ea, found only at the dealer cold start injector o-ring :mad ). Somewhere in all of that cleaning and scraping was a vacuum leak and the new gaskets finally after 18 mos exercised it! So, while performing this service I changed the stat from the 195* that was there to a 160*. Last summer the car ran well but consistently above 200*; that is just wrong IMHO. I cleaned the condensor coil and radiator and "packed" the radiator and that was the best I could get with temps regularly in the 220*+ range.

Since changing the stat I've not seen 200* yet. Actually 194* has been the warmest with the A/C on while sitting at a light in afternoon traffic. Once rolling the temp came right back down. And stays consistently around 180* in town and right down to 160* on the hiway. I know it's not quite summer yet but this early improvement has sold me on changing to a lower temp t-stat. I think now it's time to get a chip with that parameter in mind to take the most advantage of the mod. :seeya

 

I just did that on mine and got the computer programmed to turn the fans on. Now it can idle all day at between 170 - 177 degrees.

 

:nonod: :beatdeadhorse:

 

I run a 180* since sometimes a 160 thermostat will cause the car to stay in open loop for too long. Driving around in the fall/winter here, you can watch the t-stat open and close on the water temp guage and the temp rarely gets above 180. I think for a warmer climate or for the warmer times of year here in Colorado, a 160 would be fine. Especially since my car seems to like going into closed loop fairly quickly.

JMHO

Chris

 

The car is supposed to go into closed loop before it ever gets to 160 degrees. A 160 thermostat will have no effect on how long it takes to warm up to 160 either. If everything is working properly your closed loop function works just fine with a 160 thermostat.

FYI with my heated O2 sensors I've got my car set to go closed loop at 120 degrees with no trouble at all.

 

This is too cool. I have written pages on this subject, so I will keep this short. You can do a search if you want to be fully informed. The engine needs heat to operate properly. The oil has to get hot enough to boil off the contaminets that form in a cold start and warm up. Once a stat is open, it loses control of the water temp. You will still see 200 in town, (not too hot) as you did before. All you are doing is delaying the warm up from 160, up, and increasing engine wear.

RACE ON!!!

 

I agree with CFI-EFI.

I recommend switching the 160* out for a 180* (a good compromise for L98's), then have the chip-reprogrammed to work with this, assuming you're having other mods done and chip recalibrated accordingly. Otherwise, the more important and better mod is to get a low temp fan switch.


[Modified by bradvette, 12:38 PM 5/12/2004]

 

My oil temperature is consistantly hotter than my coolant temps. By as much as 30 degrees. I too run the 160 stat, but I think my oil temps are hot enough. They average over 200 degrees when my coolant temps are around 170. Are my oil temps supposed to be very close to coolant temps? I may be running too cool with the 160 and not even know it. I agree with you on boiling the contaminants. That is a fact. I just wonder if my guage is off on oil temps. :thumbs:

 

Oil temps should be higher than the water temp, but it takes longer for the oil to heat up. The big problem is with short and intermadiate length drives. Too cool of an engine will spend little or NO time fully warmed up. Water temp is not the whole story. Just remember, about the worse thing you can do to your engine, is START it.

RACE ON!!!


[Modified by CFI-EFI, 11:15 AM 5/12/2004]

 

MtlSphere, the easiest (least expensive) way to lower coolant temps overall is to install an (HyperTech) aux fan switch that brings the fan(s) on around your T-stat temp. I have a C4 Tech Tip on this. This will lower coolant temps in traffic and at idle. Though you won't maintain 160deg in head, with A/C on at idle temps will be lower.

Do not worry about your ECM not going closed loop soon enough; you can check it out with a paper clip and the method on my site.

As far as increased wear is concerned, just use a premium motor oil and change every 3k miles or 3 mo. Remember that though your crankcase temp may be lower cylinder head temps are quite high so that oil still reaches high temps on it's travels through your engine.

 

you guys are suggesting using an aux. fan with the stock 195* thermostat or with the180* thermosatat? - it would be nice to have a little heat in early spring/ late fall. Thanks for info.

 

You can use the aux fan switch to match any T-stat, where available.

I use one to match my 160deg stat, summer & winter and have plenty of heat even in SE NY & NE OH winters. And she easily passes OH emissions dyno test in the middle of Feb.

 

The 190 stat and the high temps are for emission purposes. You will achieve your goals and still have heat with the 180 & fan set-up. Best of both worlds so-to-speak and you will still have heat; not as nice as the 195 heat though. I hear it gets pretty cold up there eh? I would pop the 195 back in during the winter. It only takes a couple of minutes. :yesnod:

 

I run a 195 during the winter months for improved interior heat, but, for me, a 160 stat is too cold and a 180 is too hot (for Texas summers). So I split the difference and run a 170.

I couldn't find one that fit the Vette manifold housing, so I bought one designed for a foreign car. The OD was too large, so I just used my Mikita high-speed grinder and cut it down to the right size.

Done deal.

Jake