Depends. It wouldn't run any different but you can take advantage of the modification in the tune. If you put it in you may run cooler earlier and slightly longer due to the thermo opening up and that right there is very valuable when racing. On the street you wouldn't get anything out of it b/c of heat soak.

 

ah it won't make that much of a difference. May be a little rich from being cool but nothing the PCM can't adjust for. Don't worry about it.

 

it wont hurt anything but it wont help unless you get the fans programmed to come on at lower settings

and it wont be rich, closed loop kicks in well before 160

 

You do need to get the fans reprogrammed as you will still heat up at idle. On the road though you will be considerably cooler than with the stock stat.

Bill3508

 

Jeff probably lowered the fan settings already but for the stock t-stat. It won't hurt anything to put in the new one. And as said above, you won't run any richer from a colder t-stat...regardless of tuning.

 

Where do you guys have the on/off temps for fan 1 and fan 2? I just put a thermostat in today and I"m not sure when I should have the fans kick on!

 

Here ya go Hoss81...

Here's the stock settings.

And here's a suggestion I found from the site.
http://www.ls1gto.com/forums/showpost.php?p=1552931&postcount=10

 

No tune needed for the transmission cooler. Just decide if you want to bypass the factory cooler or not and once you connect everything up you're done.

 

The following comments are my opinion only. All standard disclaimers apply...

I put a 160 in for a day. After doing the rest of the research I should have done first (the interwebz is awesome), I put the stock thermostat back in. FYI, I'm also running a Predator 91 tune.

For one, these computer-controlled engines are meant to be run at 194*, which mine does all day long with the stock thermostat, even in the crawl of commuter traffic in the summer. Secondly, I can't change my fan on temp, so when sitting in traffic or waiting at stop lights the temp will rise up to 204 or so before the fans kick on (just like they're supposed to.) The only time the temp drops significantly is when there is sufficient airflow through the radiator. Performance-wise, I saw no difference. To me, this was a waste of money and time. Your results may be better than mine.

I now have a very lightly used SLP 160* thermostat for sale. Twenty bucks and you pay shipping.

 

Yeah, you definitely won't notice a performance gain when you put the pedal down. You're not going to feel like the car has 10 more rwhp or anything at all of that nature. But there is a noticeable difference to be had at the race track.

With my engine being as warm as it would have been with my stock thermostat at cruising speed I'll make a few passes down the track and be a little disappointed. I'll obtain this kind of coolant temperature when hot-lapping the car. With my engine being at the normal operating temperature that it would be when going down the highway, when I make a few passes at the track the ET's are as much a two tenths faster with the 160 degree unit. This is done with the transmission being at pretty much the exact same temperature on each pass (the tranny cooler keeps the trans fluid around 175-180 when running down the track) so the faster passes with the cooler motor can't be contributed to a cooler transmission, since the trans ISN'T really any cooler on one run than on another. The DA's will pretty much be the same, and the car is very consistant when the engine coolant temps are consistant.

You really do need to be able to program the fans to come on at a lower temperature to keep the coolant temps down, otherwise when sitting sill the temps will just rise up like they did in your case.

Not trying to argue with you in any way, just explaining some evidence that they DO perform better on these cars, and explaining why your results weren't as good as you hoped for. Hope that helps!

 

No worries, Andrew. I appreciate the feedback.

My car is a daily driver that never sees the track, but does see the occasional twisties in my area. It's my fault for contracting "mod fever". Once the meds kicked in and I was feeling better, I decided to get back to stock.

I am still learning, even at 50, that not all mods are appropriate for my car and the way I drive it. Now that Dashhawk has caught my eye...

 

Oh I can definitely understand. At my tender age I've learned to agree over the past several cars that I've owned and modded that not all choices I made with how far I've taken then modding have been the best decision lol. My taste is cars has changed in over the past several years... hence why after modding the heck out of a '92 Taurus SHO (yes.... you all can laugh haha) that was my daily driver has made me decide to go a with a more civil '96 Taurus SHO that I now plan on keeping bone stock as my beater lol. It happens!

Dashhawk, you say??

http://marylandspeed.com/msd-dashhawk-can-bus-vehicle-information-display-msd13100-p-739.html

There is a plethora of info in that link that you may not have read already.

 

The only reason these engines were made to run so hot is for emissions reasons. And considering that the stock fans don't even come on until 220 unless you lower them, plus the fact that the stock thermostat while rated at 186(194 actual on mine) doesn't even fully open until 210, you have nothing to loose and everything to gain by keeping your engine cooler. You won't add HP but it will prevent you from loosing HP due to the massive heatsoak problems these engines already have.

Also, the Dashhawk does look very nice. Will it tell oil pressure?



Bill3508

 

Also, the Dashhawk does look very nice. Will it tell oil pressure?

Yep, it sure will!

 

My Fan1 comes on right at 204*, at least that's the temp I see when I start the car in diagnostic mode (you know, depress the Mode and Select buttons and then turn the key). I've never seen it go over 206*, even in summer commute traffic. I don't think Fan2 has ever come on unless I have the AC on, and even then I'm not sure.

I don't necessarily need the thermostat to open fully as long as the desired engine temp is being maintained. (Isn't that the purpose of the device in the first place?) Again, I'm not a drag racer and don't have a heat soak problem that I can't live with. I have relocated the IAT sensor to minimize the effect and that will have to be good enough.

In any event, my engine temp pursuits are over. I'm moving on to the Dashhawk so I can monitor my A/F and other vitals. I can then use my Predator to fine-tune the 91 tune that I'm currently running.

I believe the Dashhawk can show oil pressure, though I already have the JHP dash gauges for that.

 

The 160* won't hurt anything. I read that the LS7 comes with a 160 stock. So I don't know why it would hurt a GTO. The only adverse effect should be when it is cold outside and you want to run the heater. It may take a bit longer to get warm depending on your degree of comfort. I put one in a 2006 GTO and it ran from 176* when cruising and went up to 192* when standing in traffic. I did reprogram the fans with a predator, however it does not have the same settings as on the 2004 GTO that I now have.

 

Great info right there ^^^^

I am glad that someone has the same info that I do on the 05-06

 

im curious too ,i cant figure it out