[HUMMERcustoms.com/TAZ]

George if Your running straight stock and not generating anymore heat than factory designed it to run at I would not change it. The main reason for changing is to help prevent detonation when You have forced induction or want to run a handheld tuner in perf. mode with 87 octane fuel. I have done it for 5 years on My Sliverado with lower t-stat, electric fans and a few more things and in perf. setting with it running very cool have had not had any problem running 87 in a 93 octane tuning. Checked for codes constantly for first year never got a detinaiton or ping code. You want to run as cool as possible if You are messing with performance. I'm doing everything i can do cool My rig down. Icebucket for fuel line for looks but, functional if needed. Water/methonal injection that works at WOT. 160 degree t-stat. electric fans which seem to pull way more air through radiator than factory. My AC improved it's cooling by almost double because of the increased air flow.
So in short if full stock do not mess with it.
I have even bypassed the water heater line to the throttle body because it does not get cold enough here for Me to need it and all it does is heat the air up coming into throttle body.
i hope i helped Gearge
George I should have mentioned the reason I run 87 in perf. is because the 87 is more unstable than 93 and generates more power. The goal in perf. Is rn tming as advanced as You can get without ping and to use the most unstable fuel You can to get more power. To do this requires the lower temp pocess. Now if it is full race rig I would have 100 octane in it because it is goig to try and detonate no matter how cool You rn it becuse of the compression ratio. 87 octane can detonate before the spark ever get's there id the compression is there along with the heat to fire it off just like desiel. It has no spark plugs but, it runs and ingnites by compression. 87 will do the same if You are not remembering that for every action there is a reaction. So 87 in high compression means reaction needs to be eveything as cool as possible so it does not detonate but, gives you more power. it is a dancing in a circle till You find the right combination. I ran until SC My H2 on perf. setting with 87 octane with all the cooling I could get and never had a problem. I experimented and ran all the 87 our of a couple of weeks with adding 93 and saw My milaege go done a little and could feel the loss in power. Went back to 87 until SC went in.
TAZ