as far as the first question look at airaid.com for your intake.

 

A colder thermostat could actually hurt gas mileage if you dont reprogram the computer fro the colder stat. The computer may not go in to closed loop operation as quick and you could end up running a rich condition. Something you have to think about w/ fuel injection if you make a mod how does it effect other things and will the computer compensate for it w/o changing the programming.

 

I've read all the responses to this thread. (LOL) Go to NAPA 'n get a 180 t-stat. Take it home 'n put it inna pot of hot water to make sure it's functional (bi-metal valve) then run cold water on it to ensure it closes. (Use tongs) do this several times. Then install it. All this 'gas milage' stuff etc. is anecdotal nonsense. Best t-stats are Robert Shaw (which was bought out recently 'n you may not be able to find 'em) I run a Moroso at present... 'just cause it came with the M-1 intake manifold. I've run a 180 since the R/T was a week old.

 

Lol my whole problem was the electric fan was out. Just now have to wait for advance to get my thermostat in since im gonna get the stage 2 chip that requires 160. I hope it works lol.