thermostat?

[98sierra71z]

hello,

 

i own a 98 gmc sierra z71 5.7 and im looking to get some gains in hp and gas mileage, ive got a cold air intake a chip and a cat back exhaust on the way but i was wondering if installing a thermostat will actually help the motor at all? is it bad for the motor and is it also hard to install? also which is better a 160 or a 180 thermostat? is there anything else that is required to do this?

 

thanks,

brian

[Nice rig]

Your not going to gain anything with a thermostat, just keep the stock one in there. The intake, chip, and cat back system sound good.

[C & A s Dad]

You may need to replace your stat as a maint. item. But as Nice Rig said, go back with the factory temp stat which is likely a 195 but I am not sure on this model. When you go to buy it, tell them you want the factory temp and I would also suggest that you do not cut corners with a cheap stat. Buy a good on like Stant and they even offer a premium all stainless unit if you want to spend the few extra bucks.

[mooreapi]

98sierra71z,

the reason that some of these performance kits use the lower temp thermostat is that they usually advance the timing somewhat and at the higher 195 degree stat setting, you can get some pinging/detonation.

Unless you use one of the reprogrammers to aggressively change your fuel curve and/or timing, changing to the lower temp stat should not be required for the mods you currently have. It will not help, and might even hurt because then your truck's PCM will think your engine has not warmed up and so could actually hurt performance and mileage. YMMV, but I would not recommend it.

 

Matt

[03TRAILEXT]

IF you want lower temps. you have to lower the fans temps.

 

You can get a tune at a speed shop or get a handheld programmer and lower the fan temp.

 

Just the stat alone will only open the water faster and will get up to normal operation just a little later.